Dometic RM2310 to 2354 in RT 170 1997

[RT1997]

I would appreciate if Roadtrek owners share their experience in taking RM2310 fridge out and installing 2354.
Not sure if the connections at the back are the same in later models of RT 170.I made a pic. of them.
I searched online but no info on exact situation.
The general idea is clear but it could be some details.
F.i. in the only video of 2310 removal the owner had trouble with some metal thing keeping it from being pooled out ( in later model of 170).
Thank you in advance for any details.

 

[RT-NY]

I think that one forum member recently had out an RM2310 (https://www.classbforum.com/forums/f5/fridge-question-14301.html) to fix the thermostat. Hopefully someone with a 2354 can provide some more information on that model. My 2310 needs news a new thermostat and a new swtich, but I am sticking with it. I expect that, even if the coil eventually fails, I will try to replace it rather than upgrading. Did your RM2310 stop working entirely?

 

[RT1997]

The fridge is still working.But a couple of years ago during normal cleaning I heard a hissing sound and found that a tiny pipe under the freezer that looks more like a wire (about 0.08 inches in diameter and just a few inhes long) is loose.I called Dometic right away.They had no idea what was that pipe for but assured me it was not freon leak.
The hissing sound stopped shortly.After that incident the freezer is not cold enough to keep an ice cream hard.The rest is ok (buttter is hard f.i.)
There is another possible damage that could appear any time. At first I did not know about the necessity of keeping the vehicle levelled and parked overnight in the driveway for a couple of months ( ticket for parking on the street).The driveway was not very steep but enough to do some damage.
The fridge also performes poorly in hot weather..

P.S. Thank you for the link.Their connections are different.
I am afraid ( after propane tank story) that 1997 was
not a good year for the RT designers )):

 

[RT-NY]

Well, before you replace it, it might be a good idea to think more about what kind of fridge you want. The 2310 and 2354 are both "absorption" fidges. They do not use freon -- that is for "compressor" fridges, like people have in their houses.

I do not know what that hissing you heard could have been, but I wonder if the thin pipe you saw was just the capillary tube, which runs from inside the fridge to the thermostat behind the fridge. It's long thin tube that acts like kind of a switch to control the temperature. It is longer than a few inches but only part of it is visible from inside the fridge.

It is possible that you disturbed that tube, or its location in the fridge, in such a way that the thermostat is not letting the freezer get cold enough (it's supposed to be against the fins, held in place by a thin piece of metal I think). But it is also true that, when it is very hot outside absoprtion fridges do not always get as cold as compression fridges do. But only absorption fridges can run off of propane, so it depends on how you want to use the fridge.

Regarding, leveling -- that is only an issue when the fridge is running, not when the RV is just parked and not in use.

Anyway, perhaps there isn't anything wrong with the fridge beyond needing a few adjustments.

 

[hbn7hj]

You will need to provide 15 amps of 12 volt DC (30 amp fuse). The 2310 has no electrical connection. Beyond that it is just a matter of hooking up the propane.

 

[RT1997]

Well, before you replace it, it might be a good idea to think more about what kind of fridge you want. The 2310 and 2354 are both "absorption" fidges. They do not use freon -- that is for "compressor" fridges, like people have in their houses.

I do not know what that hissing you heard could have been, but I wonder if the thin pipe you saw was just the capillary tube, which runs from inside the fridge to the thermostat behind the fridge. It's long thin tube that acts like kind of a switch to control the temperature. It is longer than a few inches but only part of it is visible from inside the fridge.

It is possible that you disturbed that tube, or its location in the fridge, in such a way that the thermostat is not letting the freezer get cold enough (it's supposed to be against the fins, held in place by a thin piece of metal I think). But it is also true that, when it is very hot outside absoprtion fridges do not always get as cold as compression fridges do. But only absorption fridges can run off of propane, so it depends on how you want to use the fridge.

Regarding, leveling -- that is only an issue when the fridge is running, not when the RV is just parked and not in use.

Anyway, perhaps there isn't anything wrong with the fridge beyond needing a few adjustments.

Thank you, RT-NY.
You are a wealth of knowleadge !
It is definitely the capillary tube. But it looks like it was broken or pulled out (see the pic.).That is probably how some air under high pressure made that hissing sound.
"It was not freon" - I was quoting Dometic young lady rep.
I was concerned about that sound.
When the RT was in the driveway the fridge was working on propane.I found about the levelling probably just in time.It is 9+ years since then.But some damage most likely happened.
There is another reason I would like to get a new fridge.
It might not be available later ( like there is no cooktop available for direct replacement - a major cabinets modification required).
In general I would rather have 2 way fridge (2351) since 12v is pretty useless if you have just 1 house battery.
But I decided to have as exact replacement model as possible.

 

[hbn7hj]

In general I would rather have 2 way fridge (2351) since 12v is pretty useless if you have just 1 house battery.
But I decided to have as exact replacement model as possible.

Not true. Twelve volt is only used with the engine running and has nothing to do with battery size.

 

[GallenH]

RT1997: I can't tell by your pic if the end of the capillary tube is broken off or if it is still intact. I replaced thermostat and the instructions do warn you to be careful not to damage the tube (which you should see running out of the fridge back and down to the bottom of the fridge where the thermostat is). You can't replace the tube alone if it's broken; you have to replace the entire thermostat.

RT-NY: So my thermostat replacement is working in both electrical and gas modes. What I want to add is when you get to the thermostat to replace it, you also have good access to the switch. The bottom of the switch are has a cover that you have to remove to easily get to the thermostat. Once off it's a simple mechanism, completely exposed for cleaning. I used a healthy amount of electrical contact cleaner and then a slight bit of silicone on the areas that the shaft rubs. Very smooth action now and, of course, the thermostat is smooth as it's new.

Clip at very top connects to gas valve to open valve whan in "GAS" position. Electrical contacts for 120v and 12v on exposed area of switch below.

 

[RT-NY]

Thank you, RT-NY.
You are a wealth of knowleadge !
It is definitely the capillary tube. But it looks like it was broken or pulled out (see the pic.).That is probably how some air under high pressure made that hissing sound.
"It was not freon" - I was quoting Dometic young lady rep.
I was concerned about that sound.
When the RT was in the driveway the fridge was working on propane.I found about the levelling probably just in time.It is 9+ years since then.But some damage most likely happened.
There is another reason I would like to get a new fridge.
It might not be available later ( like there is no cooktop available for direct replacement - a major cabinets modification required).
In general I would rather have 2 way fridge (2351) since 12v is pretty useless if you have just 1 house battery.
But I decided to have as exact replacement model as possible.

I think the capillary tube has fluid it in but only a small amount; the fliud expands/contracts with temperature and that switches the termostat on or off. The tube might be broken, but if so I think that the fridge would not cool at all or would get too cold, so it might have just fell down a bit from where it should be and because it is colder lower down the thermostat turns off too soon and so the freezer doesn't get as cold. Also, the tube can be replaced (it is part of the thermostat, as in the picture here: https://www.amazon.com/M-C-Enterprz-2007199009MC-Enterprises-2007199-00-9MC/dp/B01BKPVUNO) Have you tried setting the temperature dial all the way to max?

I think that the kind of damage that running out of level causes would result either in intermittent or complete failure to cool rather than less efficient cooling.

About the connections of the 2310 versus the 2354: I guess they would both require the same thing--12 volts, 120 volts, and propane. The biggest concern would be where the propane line runs and if it will line up correctly. The wires should be easy to deal with.

 

[RT-NY]

RT-NY: So my thermostat replacement is working in both electrical and gas modes. What I want to add is when you get to the thermostat to replace it, you also have good access to the switch. The bottom of the switch are has a cover that you have to remove to easily get to the thermostat. Once off it's a simple mechanism, completely exposed for cleaning. I used a healthy amount of electrical contact cleaner and then a slight bit of silicone on the areas that the shaft rubs. Very smooth action now and, of course, the thermostat is smooth as it's new.

Thank you very much for that picture! It will be helpful whenever I get to putting in a new thermostat and switch. Maybe I will go ahead and buy them now in any case. I still wonder if I can do it without taking the unit out.

 

[RT1997]

"Thank all of you for your helpful posts.

GsllenH - the tube line is most likely broken : the hissing sound was quite loud and lasted probably at least a minute.
Though I was cleaning slowly and without any tools.

RT-NY - it is on max all the time and no more ice on fins like it was before the accident.

hbn7hj - thank you for the info.I thought 12v can be used without engine running.

Btw, what do you mean - " 2310 no electrical connection ??
It is 3 way fridge and there is "electric" option on the switch.

 

[GallenH]

If you have a 3-way you can run it without the engine running. The problem is that....and I believe this is what hbn7 is telling you...the fridge on 12v draws c.10A. So if you were to run it for an hour it would eat 10AH from your house battery. If you have a 100AH battery, it will run that down to 5o% in only 5 hours. Overnight and your battery is shot. The 12v option is really only there for when you are on the road. Even then, the 12v heating element is only strong enough to maintain temperature.

Another note. Previous post referred to the temperature that you are running the absorption fridge in. My RM2310 only gives me about 40-50º below ambient outside temperature. That's fine up to when it's 90º outside. Above that the fridge will struggle to keep 40º inside. Some of this depends on how you travel/eat. For example, we never carry raw meat when it's that warm. Obviously soda/beer, veggies, prepared dishes do fine. We take ice cubes in the freezer and they've never thawed. Other strategies include letting the temperature in the fridge drop to just above freezing at night so that an 8º warm up in the day serves as a "warmup buffer."

 

[hbn7hj]

Btw, what do you mean - " 2310 no electrical connection ??
It is 3 way fridge and there is "electric" option on the switch.

My error. Of course it requires 120v and 12 volt connection.

 

[RT1997]

GallenH - thank you for the info.About 12 v - that is exactly why I called it useless - it can drain house battery in no time.It is not useless for those who turn off propane while driving.
If I swith to 120v -after that it takes hours to get back to max.cold that was on propane.It is possible that electric mode is working poorly.

 

[GallenH]

Yes that is possible. How well does it work on 120v?

 

[TomF-ClassB]

GallenH - thank you for the info.About 12 v - that is exactly why I called it useless - it can drain house battery in no time.It is not useless for those who turn off propane while driving.
If I swith to 120v -after that it takes hours to get back to max.cold that was on propane.It is possible that electric mode is working poorly.

It's true that the 12v circuit has it's limitations, but I wouldn't call it useless. I typically switch the unit to 12v when driving, and it maintains temperature fine. This is a newer Dometic 3way, and I think it has a more robust 12v heating element. The old unit had a 15A fuse for the 12v, and the new unit requires a 30A fuse, and I had to run 12ga wires directly from the battery. In addition, I installed a 100W solar panel on the roof, so if I park in the sun, there is very little draw off the battery if I continue using 12V.

 

[GallenH]

It's true that the 12v circuit has it's limitations, but I wouldn't call it useless. I typically switch the unit to 12v when driving, and it maintains temperature fine. This is a newer Dometic 3way, and I think it has a more robust 12v heating element. The old unit had a 15A fuse for the 12v, and the new unit requires a 30A fuse, and I had to run 12ga wires directly from the battery. In addition, I installed a 100W solar panel on the roof, so if I park in the sun, there is very little draw off the battery if I continue using 12V.

That could very well be. The RM2310 had a 120w 12v element and a 160w 120v element. I'm guessing that the sizing on the 12v element had to do with the stock battery. My 1997 PW had a group 24 80AH battery in the battery box but I was able to squeeze a 27 100AH battery. If you up the wattage of the heater element you also up the AH draw and the number of hours it could run.

 

[RT1997]

GallenH- I am not sure if the fridge is working on 120v at all.Since it takes little propane to operate before that accident with the tube I let it run on propane all the time.Right after the accident I switched it to electric mode but in couple of hours switched back because the ice in the freezer started to thaw.
May be after switching mode in 2310 1997 it takes very long to start cooling (like after shut off) but I did not feel like testing at the time.Recently ( just before propane tank installation ) I used electric mode once for 8 hours but the freezer was not working and may be the rest also.
I am not sure since I removed perishable items.

Tom F - even newer model of 2310 that you have works substantially more efficient.
2354 should work even better?

Though I am not so happy about electronic controls.
It is nice but if fails..
Sometimes Dometic electronic controls make simple things unreasonably complicated: new Fantastic Fan has many nice features but one stupid design - lid opening/closing also turns on or shuts off the fan.To simply open the lid with no fan running requires 2 step operation.
But battery consumption is 10 times less (or more).
So I am willing to suffer )):

 

[GallenH]

RT1997: Easy test for 120v operation would be to start with a uncooled fridge. Make sure that the RV is connected to a 120v power source. Turn the selector switch on the fridge to the "ELECT" position with the thermostat on MAX. Wait a few hours and carefully feel the flue chimney near the bottom. If it's warm, then the 120v setting is working.

If the flue feels cold, disconnect the fridge from it's electrical outlet in the fridge compartment of the RV and connect it directly to an extension cord running to some outlet in your garage/home. This bypasses any fuses/breakers in your RV. Again wait a few hours to see if it's heating the flue.

If the bottom of the flue is still not heating you need to check to see if the heating element is at fault. I can tell you an easy way to do that.

 

[RT1997]

Thank you, GallenH.Very informative and detailed instructions.I will try some time later ( may be on 2354).
Meanwhile I have a question:
if your fridge is cold and you switch from propane to electric, is electric mode going to maintain that temperature right away or several hours later and cause some defrosting of the freezer?
I understsnd that outside temp. matters.Let's assume at mild temp.