Dead Dometic RM8501
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Forum Name: Podmods, Maintenance, Tips and Tricks
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URL: http://www.rpod-owners.com/forum_posts.asp?TID=10439
Printed Date: 27 Apr 2024 at 7:06am
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Topic: Dead Dometic RM8501
Posted By: pgoelz
Subject: Dead Dometic RM8501
Date Posted: 02 Aug 2017 at 10:02am
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Hi all, Well, here we are camping with our three year old Rpod 171. And the refrigerator just died. Electronics and flame are fine. Just no cooling. After research and calls to Dometic, it looks like it is clogged.... and therefore permanently deceased. To the tune of about $1500. It has ALWAYS been run exactly level except for cooldown periods in the driveway prior to trips. Not sure what that slope is but I plan on measuring it when we get home. But here's the thing...... NOWHERE IN THE DOMETIC OR RPOD MANUAL DOES IT MENTION DAMAGE IF RUN NON LEVEL. The Dometic manual does not mention level AT ALL and the Rpod manual only mentions that it might not cool if non level. It says nothing about how far off level is too much. How the h3ll are we supposed to know that running non level will PERMANENTLY DAMAGE the fridge if NEITHER manufacturer bothers to warn us?????? We are camping right now but I intend to pursue this further when we return. Seems to me that this lack of information borders on deliberate fraud, since it creates a lovely and MAJOR cash flow replacing dead refrigerators. Note that I did call Dometic from the camper and they basically told me to pound sand..... after being unable to show me where it warned me in the manual (again, it does not). I spoke with a very firm and unpleasant person who talked over me and would not let me talk to anyone else. Just venting here.... and warning others. There is plenty of information on this issue on the web, but you have to know it is an issue before you know to do the research, right? Paul
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Replies:
Posted By: funks
Date Posted: 02 Aug 2017 at 11:12am
| Here something that might shed a little light on the problem. I have also posted some problems with my refrigerator RM8501. I found one problem with the propane regulator, it was full of oil. I ordered a new one but it hasn't arrived yet. I hope this is the problem I'm having. Were did the oil come from, will google it and your going to fine that it is a big problem. It is coming from the propane tank. So you might check your regulator. I hope this helps you out. |
Posted By: StephenH
Date Posted: 02 Aug 2017 at 11:58am
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Which means that the propane being pumped into the tank is contaminated. I noticed that with one of the recent tank fills I got that seemed to have some soirt of moisture in it as my propane line to my Coleman grill-stove had what looked like water in it and it was causing the grill-stove not to burn properly. I think that is why the Mr. Heater specifies to put a filter inline when using 20 lb tanks instead of the 1 lb cylinders. I wonder if one could be easily put inline for the R-Pod.
------------- StephenH Happy is the man that findeth wisdom,... http://www.rpod-owners.com/forum_posts.asp?TID=7712 - ouR escaPOD mods Former RPod 179 Current Cherokee Grey Wolf 24 JS |
Posted By: pgoelz
Date Posted: 02 Aug 2017 at 1:26pm
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Unfortunately that is not the problem here. The Propane Supply is fine and the stove Burns clean and strong. The exhaust coming out of the boiler in the refrigerator is too hot touch as is the refrigerant tube coming out of the top of the boiler. However, the refrigerant tube becomes room temperature by the time it reaches the first set of fins and there is very little cooling action on the fins inside the refrigerator.
Pardon the weird capitalization and punctuation. I'm doing speech to text on my phone while we're camping. I will have a great deal more to say to Dometic when we get home. I am very angry. Paul |
Posted By: fwunder
Date Posted: 02 Aug 2017 at 3:11pm
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Have you tried tapping the lines beyond where you believe the obstruction might be to maybe break up the crystals (if that's what it is)? Probably not much you can do if the crystal build up is too severe. I've never had a problem running my fridge on 1/2 to full bubble slope, but I have read of folks who do. Not sure why I knew not to run it sloped cuz it depends on gravity for the ammonia to condense and fall back to bottom and prevent it from pooling in lines. Prolly from this forum. fred ------------- 2014 RPod 178 => https://goo.gl/CV446f - MyMods and Buying Habits 2008 4Runner Limited 4.0-liter V6 Yes, those are wild ponies dining on grass while dumping tanks! |
Posted By: pgoelz
Date Posted: 02 Aug 2017 at 3:34pm
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Interesting idea about tapping the line I can try that and it certainly can't hurt. It's raining right now but when it stops I'll fire it up and give the line some wax and see if maybe I can revive the refrigerator enough to at least use it for the rest of the trip. Thanks for the tip.
Paul |
Posted By: pgoelz
Date Posted: 02 Aug 2017 at 3:35pm
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That should have read "whacks". Again I'm using Text to Voice while we're in the trailer camping.
Paul |
Posted By: furpod
Date Posted: 02 Aug 2017 at 3:36pm
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In the vintage world, many a dead refer has been restored to life with a light tapping of the lines. If it's not a leak, the "coolant" is still in there. Tapping, or even pulling the fridge and inverting it, has, again, saved many vintage fridges, including ours in the 'stream. and, the general consensus seems to be 3 degrees off level is the max it will still function.. ------------- |
Posted By: fwunder
Date Posted: 02 Aug 2017 at 3:38pm
Jeez furpod, now I got figure how much of a bubble is 3 degrees!  fred ------------- 2014 RPod 178 => https://goo.gl/CV446f - MyMods and Buying Habits 2008 4Runner Limited 4.0-liter V6 Yes, those are wild ponies dining on grass while dumping tanks! |
Posted By: Carolavan
Date Posted: 03 Aug 2017 at 8:31am
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Good luck getting a new part. We waited three MONTHS and then bought a new Norcold fridge. Dometic's service was pathetic. ------------- 2015 R-Pod 179 2016 Nissan Pathfinder Platinum "It's a good thing we are going slowly because we might be going in the wrong direction." Ashliegh Brilliant |
Posted By: furpod
Date Posted: 03 Aug 2017 at 12:55pm
I always figured if I can walk without holding on, and shower without leaning on a wall.. "close enough".. But.. for 20 years, I RV'd on a tank.. so... ------------- |
Posted By: spydie
Date Posted: 03 Aug 2017 at 11:55pm
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According to my new 2018 Dometic manual, the new refers have a "round" boiler and the old ones had a square boiler. The old ones, according to Dometic service manual (available online) would eventually plug up (a cumulative affect) and usually required replacement (although I've heard of RV maintenance guys taking the refrigerator out, rolling it over and over on the ground, re-installing it, and it was unplugged). The new round boiler supposedly doesn't plug permanently but if it stops cooling, just re-level your rig and it will start again. Some people say you have to turn it off and let it cool down first, though. ------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi 
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Posted By: pgoelz
Date Posted: 04 Aug 2017 at 7:12am
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Ours is three years old and has the round boiler. Sadly, we have tried many times.... turning g it off and letting it sit did not help at all. The inside fins get cool enough to condense water but that's about all.
According to Dometic, three degrees front to back and six degrees side to side is the limit. However, the fact that crucial information is not in the manual seems to me to be unbelievably negligent at best and intentionally fraudulent at worst. Forest River is supposedly looking into remedies with Dometic but I have not heard back yet. Not holding my breath either based on my last conversation with Dometic. Paul |
Posted By: StephenH
Date Posted: 04 Aug 2017 at 9:33am
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I'm looking at something like this if I can't get adequate performance out of our RV refrigerator. It might mean that we could not dry camp for long periods but this one looks like it would not be too hard on the batteries and yet offer superior performance to the absorption refrigerators. https://baymarinesupply.com/vitrifrigo-c115ibd4-f-marine-rv-refrigerator.html - Vitrifrigo 4.2 Cu. Ft. AC/DC Marine Refrigerator . ------------- StephenH Happy is the man that findeth wisdom,... http://www.rpod-owners.com/forum_posts.asp?TID=7712 - ouR escaPOD mods Former RPod 179 Current Cherokee Grey Wolf 24 JS |
Posted By: spydie
Date Posted: 04 Aug 2017 at 10:48am
That's not too bad of current consumption. I replaced my Dometic with an Engel (swing-compressor, like the Danfoss compressors) in my motorhome 4 years ago and it draws (rated) 1-3 amps per hour (averages a little over 1 amp in real life). I added a couple extra batteries and could run it for days with no affect. I recently took a 3 night trip in my truck to pick up my Rpod and put an Engel Chest freezer/refrigerator in the back seat and took along an extra AGM sealed battery to run it at night (because my truck 12 volt plug-in is dead after you turn the key off) and after 3 nights on that battery, when I got home it still measured 12.4 volts. I'll be adding the second battery to my Rpod and carrying the Engel with me for things that I want colder than the Dometic can handle (and I've already thought about replacing the brand new Dometic with another built-in Engel).
------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: funks
Date Posted: 04 Aug 2017 at 11:07am
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I think I'm having the same problem with our three year old RM 8501 cooling on gas. It runs on AC and DC just fine. Is yours running on AC and DC? I'm trying to nail down the problem and If I do I'll let you know. I also have a good blue flame and the tower is really heating up but it just won't cool down. Good Luck and keep posting
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Posted By: spydie
Date Posted: 04 Aug 2017 at 11:23am
Not sure who you are talking to without quoting the original poster, but I've been on here for a week or so complaining about my brand new 2018 R-pod not cooling as well on gas as on either of the electrics, when in reality, in over 40 years of Rving and a dozen or so single-door Dometics, gas has always, traditionally, been the most efficient. Right now mine is running 5-7 degrees warmer on gas than either 12 volt or 120 volt. And believe it or not, my 12 volt is the most efficient by about 2 degrees. Mine has been at the dealer all week while they try to find out why and I'll post their results on here when I get word. I don't expect they'll find anything because my propane flame is also blue and the boiler is very hot. ------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: pgoelz
Date Posted: 06 Aug 2017 at 8:37pm
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OK, original poster here and I'm back home after a week camping with my dead RM8501. Good thing we use a Coleman cooler for misc. camping stuff...... emptied it and filled it with ice and we at least didn't lose any food. 1. I measured the slope on the driveway... this is the maximum out of level I have ever subjected the fridge to. It measures 2.1 degrees fore / aft and 0.8 degrees side to side. That is well within the 3 degree / six degree spec I got from Dometic when I pressed them. So I didn't kill it like I thought I might have. However, the first owner might have. In either case, without any warning from either Dometic or Forest River, how should either of us have known? 2. I tried re-starting it several times perfectly level and on gas while we were camping this week. Each time, the left side of the freezer fins got cool enough to condense but the right side and the entire lower fins were still at ambient even after several hours. Definitely not normal. 3. When we returned home, I un-hitched, leveled the trailer and started the fridge on AC shore power. To my amazement, it is cooling normally. The freezer fins are frosting up and the internal temperature is 43 degrees (and I assume still dropping) three hours later. Tomorrow I'll switch to gas and see if it can hold temperature. Maybe the sloshing of the 500 mile trip home while powered off "burped" something? 4. If it cannot cool on gas, I'll have a closer look..... while on gas, the flame DOES light, the controller sees the flame and does not sound any alarm and the exhaust out the top of the flue is very hot. But I have not checked for internal flue obstructions or actual flame size. I'm also wondering if perhaps the flue and the boiler tube have become separated so there is not sufficient thermal transfer? I don't know how it is built.... if the cooling unit is replaceable, they can't be welded. Perhaps they have just lost mechanical connection? Or perhaps the flue is actually part of the boiler? Paul
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Posted By: pgoelz
Date Posted: 07 Aug 2017 at 5:23am
The fridge was at 36 degrees after running four hours on AC shore power in the driveway. I figure that is pretty normal. So before we went to bed I switched to gas. This morning the interior is at 50 degrees and rising, same as when we were camping. So it is definite. The cooling unit is fine..... we just have a much simpler (and less expensive) issue with the flame or flue. The flame is on and satisfying the flame sensor but beyond that I could not see enough of it through the match light hole to see how big or blue it is. Today I'll dig into it and see what the real issue is. Paul
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Posted By: Tars Tarkas
Date Posted: 07 Aug 2017 at 5:54am
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You aren't lighting the flame with match are you?? If you are, that's an important clue. TT ------------- 2010 176 FJ Cruiser |
Posted By: pgoelz
Date Posted: 07 Aug 2017 at 6:21am
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No, I'm not lighting with a match. I'm just looking through the hole to see if the flame looks OK. The flame lights fine automatically, satisfies the flame sensor and there is heat coming out the top of the flue. But I can't see enough of the flame through the hole to see how big it is or what color it is from bottom to top. This is starting to make some sense. Two trips ago we ran out of propane way before I thought we should. I put it down to simply mis-judging the amount of propane we had remaining. But now I am guessing the cooling on propane was getting worse and worse and the flame ended up on 100% of the time.
Propane pressure to the fridge seems OK.... the stove burner has a normal size flame and does not change size when I light the second burner. My guess is that the fridge burner orifice is clogged or there is something in the flame tube. Our (smaller) fridge in our pop up ran fine for 15 years without any burner maintenance so I kinda overlooked the burner maintenance mentioned (but NOT described) in the RM8501 manual. Can't wait to tear into it and see if it is as simple as a clogged orifice. I have a small ultrasonic cleaner that should work great with a bit of alcohol to clean it out. I am of course VERY relieved that the cooling unit itself appears to be perfectly OK! Live and learn.... I thought that if the flame was lit and the flue exhaust was hot, all was OK. Perhaps not..... And now that I think about it, when all was well I remember hearing the flame kind of "pop" when it lit. I could hear it inside the trailer if it was very quiet. Now I don't hear that.... the sparker stops sparking when the flame lights but I don't actually hear it light. Another indication of a clogged orifice or low pressure I think. Stay tuned. I'll report back after I have a close look at the burner later this morning. Paul |
Posted By: sailor323
Date Posted: 07 Aug 2017 at 7:03am
| Years ago, I had a kerosene fridge that occasionally stopped cooling. Flame was OK, heat coming out of the chimney, etc. I found that turning the fridge on its side, the side where the riser tube was, it would cool again when set upright and the burner lit. I theorize that somehow the cooling system developed a gas lock which prevented the circulation of the refrigerant. It will be interesting if the ride home "fixes" your fridge. Are there lots of hills and maybe bumpy roads? |
Posted By: pgoelz
Date Posted: 07 Aug 2017 at 8:57am
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The ride home did NOT fix the fridge. When we got home it cooled fine on AC shore power but still would not cool at all on propane. I just finished cleaning the burner, orifice and flue this morning. Nothing looked plugged but the orifice is so small that it is difficult to judge if it is partially clogged without a microscope. My 10X jeweler's loupe was not enough. After cleaning and re-assembly, the first difference I noticed is that I now can hear the flame "pop" from inside the trailer when it lights.... I used to be able to hear that but not recently. I can also hear a very slight roar from the flame... don't think I could hear that before I cleaned it but I was not paying close attention to the sound. My guess is that the flame is now larger than when it was not cooling. It has been on gas for 30 minutes now and the fridge IS starting to cool down. The freezer fins are very cold but not frosting yet. The lower fins are also cold..... when it was refusing to cool, the lower fins never went below ambient. We'll see how it is after three or four hours..... on AC, it was able to reach 36 degrees in that time span. So I am cautiously optimistic. I found the service manual online. I can't believe it, but Dometic species that the burner should be cleaned at least once a year but they don't bother to tell you HOW. And this is the SERVICE MANUAL. Like the lack of any leveling warnings, they seem to assume everyone has ESP. Yes, it is pretty obvious how to clean it when you take it apart. But there at least should be a warning about not poking the ruby crystal ;) Paul
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Posted By: funks
Date Posted: 07 Aug 2017 at 8:57am
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I'm having some of the same problems on my RM8501. On AC the temp will drop down to 38 but switched to gas it goes back up. When on gas freezers working ok but bottom section is still warm. The unit looks and fills like its working just fine on gas but something is wrong. I cleaned the gas orifice and burner that did not even look dirty and still no improvement. Good flame and heat but no bottom cooling. I order a new gas orifice and a thermistor for the bottom fine in the frig. Will install next week. I'll let you know how it works. |
Posted By: pgoelz
Date Posted: 07 Aug 2017 at 9:58am
UPDATE: After cleaning, it has been on gas for a little under two hours now and A) the freezer fins are frosted over their entire width, B) the lower fins are cold and C) the fridge interior is already down to 39 degrees (outside ambient is 71 degrees). That is way WAY better than before I cleaned it and I am assuming is fairly nominal performance. I am VERY relieved to put it mildly ;) Paul ADDENDUM: After 2.5 hours on gas at one step below the max cooling setting, the interior is down to 34 degrees at an external ambient of 72 degrees. I changed it to the middle setting and we'll see where it settles. This would appear to be entirely nominal operation, and all I did was clean the gas orifice. The trailer is three years old and we are the second owner. I suspect the gas orifice was never cleaned since new. Problem solved and lesson learned. I am still stunned that there are no leveling warnings anywhere in the documentation, but at least our fix was simple and we didn't kill the cooling unit.
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Posted By: pgoelz
Date Posted: 07 Aug 2017 at 10:12am
That sounds pretty nearly identical to my original problem.... works OK on AC but does not cool at all on gas even though the flame is lit. In my case, the orifice did not look dirty either but after I cleaned it (alcohol and an ultrasonic cleaner), it seems to perform like new. See above. Note that if the flame is lit, the problem is NOT the thermistor. If the thermistor is shorted, the unit would not call for cooling and the flame would not be lit. If the thermistor is open, the unit would call for continuous cool. If it cools OK on AC power, flame but NO cooling would indicate the flame is either too low or something is blocking the flue. A very unscientific measurement.... at least on mine, the flame was silent before I cleaned the orifice. After I cleaned it, I can hear a very subtle roar when the flame is on with the cover removed and I can hear it gently "pop" when it lights standing next to the fridge inside the (quiet) trailer. Paul
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Posted By: Wood River Pod
Date Posted: 07 Aug 2017 at 11:31am
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Paul, Great to hear that you figured it out and it's working. Way to stick with it! Based on your comment that the Dometic service manual does not do a good job (or no job) of explaining the annual cleaning procedure, would you be willing to please put together a quick run down of what the steps are to clean the burner, orifice and/or other. I personally have no knowledge to take that project on, but I can follow directions very well. I'd even help you to include some pictures along with the steps. Based on all of the comments from your post, I think the community would greatly appreciate the info, and it will be an education for me. I don't think I've seen a post that details the cleaning process in detail. There are a few YouTube videos, but none specifically for the pod model fridge. Send me a PM if you are interested. I think pictures would be most helpful. Thanks Jeff ------------- Smith's in Hailey Early 2017 179 HRE http://www.rpod-owners.com/forum_posts.asp?TID=9134&PN=1&title=wood-river-179-mods - Wood River Mods |
Posted By: fwunder
Date Posted: 07 Aug 2017 at 12:13pm
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This was my experience about a year ago. Model RM8501. Perhaps the pics might help: http://www.rpod-owners.com/forum_posts.asp?TID=8779&title=fridge-not-cooling-on-propane-fixed - http://www.rpod-owners.com/forum_posts.asp?TID=8779&title=fridge-not-cooling-on-propane-fixed This past weekend, the problem reappeared. Cooled fine on AC, but not on propane. My best guess is that somewhere along the road I got some dirty LP and this is the reason I have had to repeat this procedure several times. Easy to do, but a filter would be better. This AM, I repeated the cleaning above. It's cooling fine now on LP (after about two hours running). This time I am measuring boiler temp with infrared thermo @ top of boiler mantle. Perhaps I can use this temp as a diagnostic tool in the future. Seems to be holding steady @ 280-284.  fred
------------- 2014 RPod 178 => https://goo.gl/CV446f - MyMods and Buying Habits 2008 4Runner Limited 4.0-liter V6 Yes, those are wild ponies dining on grass while dumping tanks! |
Posted By: spydie
Date Posted: 07 Aug 2017 at 12:21pm
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I just made a trip to my local RV dealer to see how they are progressing after a week with my new 2018 Rpod refer (which cools fine on AC and DC but runs 5-7 degrees higher on LP). They were able to duplicate my complaint while the Dometic was in the Rpod. But Dometic told them they had to take it out of the Rpod to run the tests, so when they put it in the shop, it's working fine, about 34 degrees only turned up about half way on the temp controller. He said that today he's going to call Dometic back and discuss the mounting in the Rpod. He said the sides were hot when he took it out and that indicates the insulation is packed too tight. He's going to discuss all the mounting problems with them and see if there is some way to increase efficiency. I'll let them have it another week and see if it does any good for me. ------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: pgoelz
Date Posted: 07 Aug 2017 at 12:26pm
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Let me see if I can run through the cleaning steps I used here..... this refers to the RM8501L. And of course, turn the gas and the refrigerator off before you start ;) 1. Remove the screw securing the sheet metal burner cover. 2. Use a 7/16" open end wrench to un-screw the gas pipe nut where it enters the VALVE assembly (NOT the burner). I found that it is safer to remove the burner and pipe as one and disconnect the pipe from the burner in a controlled environment since the orifice is a little piece that fits into the burner and can easily fall out if you remove the pipe from the burner in the fridge recess. 3. Remove the screw securing the burner to the flue and then remove the pipe from the valve. 4. At this point, the igniter and flame sensor are still attached to the burner. Remove the screw securing the igniter bracket and the burner and pipe can now be removed from the fridge enclosure. 5. In a controlled environment (ie., where you can find stuff you drop), disconnect the pipe from the burner block and carefully remove the orifice. The orifice is basically a cupped washer with a tiny hole. The hole is actually a ruby with a hole in it so that it does not erode from the gas passing through it. 6. I used alcohol in an ultrasonic cleaner to clean my orifice. Not sure if you can just soak it and swish it around in a dish and get the same results. I am also not sure what is actually the best solvent to use. I have seen alcohol, carburetor cleaner and soap and water mentioned, but I don't know what we are trying to dissolve.... dust and dirt, or something gummy from the gas? There are plenty of warnings online to NOT use any sort of implement to poke through the orifice, since you can damage the opening. 7. Blow out the pipe with compressed air and also inspect the burner block to make sure nothing has made a home in there..... the burner block is where the gas jet mixes with air and then flows upwards where it ignites. There is plenty of room in there for spiders and critters. 8. Remove screw securing the "T" cap from the top of the flue and remove the cap. Remove the baffle that is suspended in the flue on a bent wire. Pass a small bottle brush through the flue to make sure it is clean and un obstructed. In my case I didn't have a bottle brush so I used a wadded up piece of paper towel and pushed it down with a plastic pushrod. BAD MOVE..... it got stuck half way down and I thought I was in serious trouble for a while. Not sure if there is structure in there or what, but I finally got it to pass all the way through and since it came out intact I figured all was well. Finish off by blowing some compressed air down the flue if you can. 9. Re-assemble and test. My best guess is that stuff sticks to the edges of the orifice and slowly closes it off, gradually reducing the size of the flame. Cleaning restores full flame. I am trying to figure out how to gauge the cooling efficiency. Since there is no indication of when the flame is on and no way to determine what the stabilized duty cycle is, I can't figure out how to tell if I am completely back to normal. But it SEEMS to be normal. Paul
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Posted By: spydie
Date Posted: 07 Aug 2017 at 12:54pm
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From the Dometic manual: Determine if the refrigerator works on one heat source but not another by testing it in the alternate modes. Also, ask the customer if he gets better cooling results from one energy source than another. If this is true, it indicates the problem is NOT in the cooling unit. Also it says not to use compressed air to blow out the orifice. Clean in alcohol and let it air dry. If anyone would like a copy of the service manual, I'm hosting a copy in my dropbox at this address: https://www.dropbox.com/s/32i0fssts7yrw61/dometic-service-manual%20copy.pdf?dl=0 ------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: Wood River Pod
Date Posted: 07 Aug 2017 at 1:15pm
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Fred, thanks for the link back to the previous post. I kind of remember seeing that right after we bought our 179. Paul, thanks for the step by step instructions. Most helpful! I so appreciate the level of knowledge and the willingness of this community. Thanks ------------- Smith's in Hailey Early 2017 179 HRE http://www.rpod-owners.com/forum_posts.asp?TID=9134&PN=1&title=wood-river-179-mods - Wood River Mods |
Posted By: pgoelz
Date Posted: 07 Aug 2017 at 1:36pm
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And thanks for the link to the service manual. Note that is NOT the RM8501 manual (which can be found on the net) but there is a LOT more detailed operational and testing information in the one you linked to vs. the actual RM8501 manual. I put a remote reading thermocouple (former engineer here) in the fridge so I can keep tabs on the internal temps without opening the door. Looks like on the middle setting, it is holding right at 41 degrees. I'll call Dometic and see if I can get them to tell me if that is nominal or not. I suspect it is. Paul
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Posted By: spydie
Date Posted: 07 Aug 2017 at 1:45pm
Paul, There are a lot of variables and I doubt there is any "Normal." If it's 70 degrees outside the temperature in the fridge will be a lot different at any setting than if it's 100 degrees outside. And we found out today that it makes a BIG difference if the unit is IN the Pod or sitting on a test bench. Because of the refer being in a slide-out, they unable to put a roof vent (which would be a lot more efficient) and these Dometics apparently lose a lot of efficiency just because of being mounted in the RV. Dometic will tell you the only way they accept temperature readings is if you are doing the "water test." That is, a glass of water in the fridge with a bulb thermometer in it. It's the only way they'll accept readings from a service department (as my service department told me today after they've been talking to Dometic service directly). I didn't realize the service and diagnostic manual I posted was not for the 8501, but you're right, it does have a lot of information in it. ------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: marwayne
Date Posted: 07 Aug 2017 at 2:00pm
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Here is what I do. If I stand about 2 or 3 feet away from the fridge outside and I can't hear the flame clearly the burner and orifice needs cleaning. I clean mine once or twice a season. ------------- If you want something done right, do it yourself. 2011 RP172, 2016 Tundra 5.7 Litre, Ltd. |
Posted By: spydie
Date Posted: 07 Aug 2017 at 2:02pm
I'm going to check that very same thing on mine when I get it back from the service department (of course a lot of that test depends on your hearing! LOL)
------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: pgoelz
Date Posted: 07 Aug 2017 at 2:11pm
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I read somewhere that if you are using a remote reading meter to measure internal temperature, the water glass is not required. They simply want to ensure that the temperature is the actual internal temperature PRIOR to opening the door and the glass of water slows down any temperature changes when the door is opened. I think I'll give it a rest for now. After cleaning the orifice, it has gone from ZERO cooling on gas to frost covered freezer fins (freezer compartment removed) and a steady 41 degrees on middle setting (36 degrees on middle + 1 setting) at a 74 degree external ambient. My interpretation is that the absorption process is kinda binary.... below a certain amount of input heat, the circulation / cooling stops altogether instead of tapering off linearly in spite of continued heat input. So if the flame is present but reduced in size due to a dirty orifice, you might have no cooling on gas..... as in my case. I have also found that the Dometic manuals are amazingly pathetic. For example, they show you (with PICTURES, even) how to make ice in two paragraphs.... paragraph 1 shows putting water in the ice cube tray (with photo) and paragraph two shows placing the ice cube tray in the freezer (with photo). Golly, how would I EVER have figured that one out??? By contrast, the troubleshooting section under "refrigerator does not cool adequately" completely omits checking that the unit is level. Paul
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Posted By: spydie
Date Posted: 07 Aug 2017 at 2:52pm
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Correct me if I'm wrong, but Dometic wouldn't accept my remote refrigerator sensor (an outdoor thermometer) even though I checked the calibration with a bulb thermometer. They claim the only reading they will accept from the servicing dealer is the 'water glass' test. I don't know what kind of sensor you are using nor how accurate it is, nor where you have it placed (that makes a big difference), but I'd like to know more about it, please? ------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: pgoelz
Date Posted: 07 Aug 2017 at 3:31pm
I'm just using a http://www.ebay.com/itm/Digital-Thermometer-Thermocouple-Sensor-2-Channel-2-K-Type-Temperature-Meter-/182481452135?hash=item2a7cbdfc67 - $20 dual thermocouple meter I bought on Ebay to measure model helicopter motor temperatures . It seems pretty accurate... within a degree at worst. Since it has two thermocouple inputs (and came with two thermocouples) it can even make delta measurements if you want. I placed a single thermocouple in free air between the rods of the lower shelf. Final stabilized measurements at 74 degrees ambient and at the middle setting after a couple hours operation are: PROPANE = 37 degrees 120VAC = 40 degrees I'm not sure I could hear the flame from a couple feet away but I can definitely hear it now with my head near the lower vent. Paul |
Posted By: spydie
Date Posted: 07 Aug 2017 at 3:37pm
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Tell me what a delta measurement is please ------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: pgoelz
Date Posted: 07 Aug 2017 at 4:00pm
A "delta" measurement is the difference between two values. Delta = value 1 minus value 2. For example, put one thermocouple in free air outside the trailer and the other in the refrigerator. The DIFFERENCE between the internal and external temperatures is the "delta" temperature. You will find some refrigerators (especially thermopile refrigerators like simple electric coolers) have a specified minimum delta temperature, which would be a measure of their ability to cool. I think my Coleman electric cooler is spec'd at something like 30 or 40 degrees.... the inside will be 30-40 degrees cooler than the outside ambient. I'm sure our Dometics have a minimum delta spec but I doubt Dommetic will share it with us. Much easier to claim proper operation when all specs are as vague as possible ;) Paul
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Posted By: fwunder
Date Posted: 07 Aug 2017 at 4:19pm
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I'm guessing it's easier to specify a delta of 30-40 degrees with thermoelectric (thermopile) coolers because they are almost always surround by ambient air. An RV installation of the absorption fridge can vary wildly as well as environment surrounding fridge. In warm or hot weather, I will run the pod AC in my driveway to noticeably make a difference in fridge performance before loading (front side considerably cooler than back side). My ideal arrangement would be a NovaKool compressor fridge only and a Dometic Portable setup as a chest freezer. More cold beer, more solid ice cream! fred
------------- 2014 RPod 178 => https://goo.gl/CV446f - MyMods and Buying Habits 2008 4Runner Limited 4.0-liter V6 Yes, those are wild ponies dining on grass while dumping tanks! |
Posted By: pgoelz
Date Posted: 08 Aug 2017 at 6:50am
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BTW, does anyone know what the brass thing is in the incoming propane line in the refer compartment just ahead of the gas valve? It is a solid brass block with a hex screw cap on the side. Is it a regulator? If so, does it require maintenance? Because it is not officially part of the refer, it is not in the service manual. Just curious. Paul
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Posted By: StephenH
Date Posted: 08 Aug 2017 at 11:08am
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Is it a port to check the gas pressure?
------------- StephenH Happy is the man that findeth wisdom,... http://www.rpod-owners.com/forum_posts.asp?TID=7712 - ouR escaPOD mods Former RPod 179 Current Cherokee Grey Wolf 24 JS |
Posted By: pgoelz
Date Posted: 08 Aug 2017 at 12:24pm
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Good guess.... better than any of my guesses ;) Not sure though. Paul
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Posted By: spydie
Date Posted: 08 Aug 2017 at 12:36pm
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Still reading the latest service manual and their new design is both interesting and a welcome change: In recent years Dometic has engineered a new type of cooling unit that utilizes an improved siphon pump tube design which drastically reduces the possibility of permanent damage to the coils if operated in an out-of-level condition, or too much heat is generated at the boiler section. As we can see from this drawing, the siphon pump tube is enclosed in the design and is surrounded by a weak ammonia solution, which will protect the pump tube from abnor- mally over-heating. This type of unit; however, does not eliminate the need for proper leveling. The unit still requires gravitational flow to provide the proper cooling process, and if leveling is outside the necessary limits, cooling will dramatically slow down or stop completely. The cooling coils are not normally damaged in this fashion and once proper leveling is main- tained, the cooling process will resume. Spirit or bubble levels are no longer being supplied with the new style refrigerators as the RV or vehicle only needs to be leveled so it is comfortable to live in, with no noticeable sloping of the floor or walls. For diagnosis, the new style cooling units that incorporate the protection boiler system, can be differentiated from the older style coils by the shape and design of the outer boiler box cover on the rear of the cooling unit. These units will incorporate a circular metal cover, while the older style utilizes a square shaped enclosure. We will discuss diagnosis and troubleshooting of these units in more detail later in the program.
------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: pgoelz
Date Posted: 08 Aug 2017 at 12:57pm
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Is there an online source for that service manual? It is definitely NOT what I have.... mine claims to be an RM8xxx service manual, but I didn't see anything about a new cooling unit design. And yes, ours is round, not square. Ya know, this just makes me even more angry! After all the trauma last week while camping with our dead refrigerator and on the phone with Dometic, they still told me the max tilt before PERMANENT damage was 3 degrees! And I told them what model and year my fridge was! Their position was that if I had operated our three year old RM8501L more than 3 degrees off level, I had destroyed the cooling unit and they would do nothing for me. They also swore up and down this information was in the manual. When I pointed out that in fact it WAS NOT, they backed down from that claim but still said it was my fault for operating off level. It was a very carefully worded statement that I was told was "what they were supposed to tell" people like me. I could not even get a word in edgewise.
Of course, as it turned out (earlier in this thread) I measured our driveway and had NOT operated more than 3 degrees off level and it turned out the problem was NOT the cooling unit. But the massive mis-information and lack of information coming out of Dometic boggles my mind. Sorry... even though we had a happy ending when we got home and could carefully troubleshoot on shore power, I am still reeling from the experience after spending our camping time preparing for a >$1000 expenditure to fix the refer. Dometic should be ASHAMED of themselves for putting us though that. Paul |
Posted By: mjlrpod
Date Posted: 08 Aug 2017 at 1:09pm
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Well, 3 degrees is equal to 3 3/4 inches from side to side of the pod. So the door side can be 3 3/4 inches higher or lower than the hook up side. Incase you wern't sure. ------------- 2017.5 Rp-172 2020 R-pod 195 2015 Frontier sv 4.0L 6cyl I'll be rpodding |
Posted By: spydie
Date Posted: 08 Aug 2017 at 1:13pm
Paul, I posted this yesterday. It's the service manual Dometic and my RV service company and I use: https://www.dropbox.com/s/32i0fssts7yrw61/dometic-service-manual%20copy.pdf?dl=0 ------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: sal
Date Posted: 17 Aug 2017 at 1:21am
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I never really use mine. My wife would like some drawers. I just may take out my refrigerator,151, and build something there. For sure if it breaks.
Sal ------------- Love Camping |
Posted By: pgoelz
Date Posted: 17 Aug 2017 at 6:06am
Oh, I am VERY sure. I fly model helicopters and I have a digital pitch gauge so I measured the pod when it was attached to the TV on the driveway ;) As it sat, it was around 2.2 degrees off level. Since that is the most off level I have ever exposed it to with the refer running, hopefully I didn't do any damage at all. And obviously I didn't kill it.... the problem was a partially plugged burner. In my research, I found a company that makes an aftermarket boiler high temperature shutdown unit. Costs about $180 and might be well worth it. Shame on Dometic for not including that feature in the first place even as an option). Yes, I'm still mad. Paul
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Posted By: spydie
Date Posted: 17 Aug 2017 at 8:01am
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I got my pod back after two weeks with the dealer and they couldn't fix it. Dometic said they could only test it if it was OUT of the pod, on a test bench. So they did that and it worked fine inside. Put it back in the Pod and it still wouldn't cool properly on LP. I took it home and called Dometic and said I wanted a new refer. They said it has a 2-year warranty and that the only the dealer could request a warranty replacement, so I took it back to the dealer and they are now trying to get a replacement. ------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: pgoelz
Date Posted: 17 Aug 2017 at 12:32pm
Do you know if they compared the gas pressure on their bench to what it is at the refer in your trailer? That would affect the size of the flame and could explain the lack of cooling in the RV. Paul
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Posted By: spydie
Date Posted: 17 Aug 2017 at 1:03pm
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That's a good question Paul. I ask them ------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: pgoelz
Date Posted: 17 Aug 2017 at 2:52pm
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In the mean time, it is not hard to clean the gas jet. If the pressure is OK in the trailer, a clogged gas jet would produce your exact symptoms (assuming it cools OK on AC power). If their bench test pressure is higher, it could overcome a clogged gas jet and produce adequate cooling. It doesn't seem linear.... below a certain flame size, you get zero cooling even though there is a nice blue flame. That was my issue earlier in this thread. Look at me.... two weeks ago I didn't know much of anything about how these things work. Its amazing what a little head scratching and research can teach you ;) Especially with an engineering background.
Paul |
Posted By: spydie
Date Posted: 17 Aug 2017 at 2:55pm
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They told me that when they had it on the bench they took the jet out and cleaned it in alcohol. ------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: spydie
Date Posted: 17 Aug 2017 at 3:15pm
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OK, just got back from the RV dealer. They've been working with Dometic for the last week (again) and Dometic now says it's a Forest River problem. Forest River did not mount the Dometic correctly. He is now working with Forest River (sent them 15 pictures) and waiting to hear from them. We all know that FR isn't going to take ownership of the problem any more than Dometic will unless there's a class-action lawsuit that forces them to recall the R-pods and mount the Dometic differently. So I'm pretty sure that after the dealer has it another week, they'll tell me it's my problem because nobody wants to fix it. My options at that point are 1. only camp in colder weather so the refer works OK or 2. replace the Dometic with a real refrigerator like the Engel I built into my last RV or 3. trade it off for another brand that may or many not work better. By the way, they pressure tested the LP both in the Rpod and on the bench to make sure it was OK in both settings. ------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: pgoelz
Date Posted: 17 Aug 2017 at 3:26pm
Well, so much for my best shot ;) If the jet is clean and the pressure is within spec, not sure what else it could be. Do we know for sure that simply swishing it in alcohol is sufficient? When I cleaned mine it was alcohol in an ultrasonic cleaner, which might have been more thorough. Mounted it incorrectly? How is that even possible? That said, when I was talking to Dometic, they raised the possibility it was not level in the trailer. Again, not sure how THAT is possible either so I guess they are just taking pot shots. Paul
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Posted By: spydie
Date Posted: 17 Aug 2017 at 3:35pm
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In my opinion, which isn't worth much, I think the absorption refrigerator is antiquated and needs to be abolished. They've never been efficient in an RV if you travel in warm/hot weather. They were developed for household use and I'm sure they are fine in that capacity, but even then they were replaced with more efficient compressor refrigerators. So what did we do? We took something that was replaced with something better for the household, and tried to put them into RVs where the OAT has a major affect on them. I have heard from a lot of people on different forums about the lack of the Dometic working properly in the Rpod, and there's no correlation between which models it's in. There's a small chance that Forest River needs to re-design the mounting area. The only people that aren't complaining much are the ones that live in cooler climates than the HOT southwest and never travel to hot climates in the summer, so they don't really know how bad an absorption refrigerator is. Other people just give up and carry an ice chest or, like me, a real compressor chest/freezer along for the campouts. Of course the Rpods are built in Indiana and Washington... they don't know what hot weather is and have never researched it so they have no idea that their design, if improved, could solve the problem of the inefficient Dometic. And they don't care. ------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: spydie
Date Posted: 17 Aug 2017 at 5:21pm
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Just picked up my Rpod at the dealer. Dometic says it's not mounted properly and it's all Forest Rivers fault. It doesn't have enough space around it so it can breathe and cool properly (the insulation is packed way too tight and the sides of the Dometic get hot). Dometic looked at 15 pictures the dealer sent them of the installation and they said there's no way it can cool properly in there, there's no space around it. All the information has been sent by the dealer to Forest River to see what their reaction is. Probably won't hear from them, but if we do, they won't take any blame with "we've been building them like that for years and nobody else has complained." (yah, right!). Buyer beware. Anybody want to buy a real nice 2018 rpod 176? Cheap! NEVER USED FOR CAMPING. LOL ------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: fwunder
Date Posted: 17 Aug 2017 at 9:10pm
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Sooo, after all this... What is the consensus for "proper" or "adequate" cooling? Speaking for myself and measuring carefully with "normally" full freezer and refrigerator areas, I have no problem maintaining 31-36 degrees in fridge and 10-20 in freezer. Using digital (Accurite), analog and Thermopen, I've been doing some testing the last few days in my driveway. Full sun and 80-85 degrees, no AC running (so it's 90+ in pod). I have tested both AC and propane. To simulate normal packing, I have several prefrozen freezer packs in freezer portion and two six-packs of 16 oz. soda in fridge. BTW, an evaporator (fin) fan is a total waste of money in the fridge. I'll write more about that later. Suffice to say fan motors give off more heat than the benefit of moving air *in* the fridge. Just curious if anyone has any one else has carefully measured fridge/freezer temps in their rPod? fred ------------- 2014 RPod 178 => https://goo.gl/CV446f - MyMods and Buying Habits 2008 4Runner Limited 4.0-liter V6 Yes, those are wild ponies dining on grass while dumping tanks! |
Posted By: spydie
Date Posted: 17 Aug 2017 at 9:19pm
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At 80-85 degrees it may work ok. We are talking 95-100 temps here in the great SW. Dometic will only accept temperature measurements via water test. A glass of water measured with a bulb thermometer. My temps were carefully measured the only acceptable way and monitored by dometic. 34-36 degrees at night when it's less than 70s degrees outside and climbs into high 50s and low 60s during the day in 95-100 degree heat . That's totally unacceptable for camping. 42 degrees is the least acceptable for dairy products. ------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: pgoelz
Date Posted: 17 Aug 2017 at 10:13pm
With you there ;) But is there anything on the horizon that is capable of replacing the absorption fridge? Ie., a refrigerator that runs with minimal to no electric power? Something that does not use electrical power for the cooling process itself? Something that does not require 200-400W of solar and golf cart batteries? Paul
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Posted By: spydie
Date Posted: 17 Aug 2017 at 10:23pm
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Ha ha. Yes. I just tested my Engel chest freezer/refer on an 80 watt solar panel and 75 amp/hr deep cycle battery and it can easily keep up. The Engel draws only about 30-40 watts or about 1.7 average amps per hour. Swing compressors draw little current. I used a built in one in my last RV for almost four years on about 200 amp/hr of batteries (three 12 v batteries ) and we dry camped all the time. Spent six weeks going to Alaska and only spent three nights in campgrounds. It's possible to run a 12 v compressor refrigerator in place of the dometic with only slightly more battery power and a solar panel really helps. ------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: spydie
Date Posted: 17 Aug 2017 at 10:57pm
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I predict that within 5 years we'll be using Thermal Electric Generators (TEGs) to produce the 12 volts we need to run our swing-compressor refrigerators and the power will be produced by an LP flame that we now use for our absorption refrigerators. We've had TEGs in the military and commercial world for decades and they are just now starting to get to be more efficient and cost affordable. I think those would be the salvation for the obsolete absorption refrigerator. And they might even be able to extend dry camping times if we can get enough out of them to run the refrigerators and keep the batteries charged. Kinda like a solar panel that runs on an LP flame. But of course then we'll have to carry more LP! LOL . Nothing is free ------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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Posted By: spydie
Date Posted: 20 Aug 2017 at 4:31pm
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I installed a 3" computer fan at the top vent and it significantly helped with the cooling. So I took out that stupid 3" fan Dometic or FR put on the bottom of the coils that only turns on when it's way past time you should have some cooling help, and I then mounted it next to my first 3" fan. Not sure two fans do much more than 1 fan, but I figured, "why not?". each fan draws about 0.15-0.16 amps so I have better cooling for about 3/10s of an amp and I put a switch on them so I can manually turn it off in colder weather when I don't need the help. Forest River has never replied to the dealer's complaint yet. It's still several degrees more efficient on electricity than it is on LP but I guess I'll just have to live with that. I'm able to keep it under 42 degrees now (just barely) in 99 degree weather in the middle of the day. It gets down to 32-34 degrees at night (depending whether it's on electricity or LP). ------------- 2018 R-pod 176 2017 RAM 1500 5.7L Hemi
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