3 year old Dometic doesn't work

[Aage]

Originally Posted by Jammer

Can't you just put some insulation over the separator?

From reading Buttercup's saga, it strikes me that a key issue is to have lots of air blowing over the cooling parts of the workings. I'm guessing that adding insulation to it could block airflow over the cooling fins.

[Buttercup]

Originally Posted by Jammer

Can't you just put some insulation over the separator?

Actually, I was thinking of doing exactly that, putting some fiberglass wrapping on the piping but then I would have to wonder if that would be advisable. Actually, it is working so well now throttling back on the airflow that I think I won't do much more than monitor. But I wonder what other changes I could make, like variable thermal input.

[doorgunner]

how about just having a martini and taking a nap.

[SuperTrouper]

Originally Posted by doorgunner

how about just having a martini and taking a nap.

Yes, Problem solved! zzzzzzzzzzz

[Buttercup]

You can't diagnose some of these things with too many martinis in yer belly. Sometimes you need a clear head to figure out the problem. Yes, this is ME talking.

[doorgunner]

clear head ? sounds like some Navy lingo to me.
the nap does wonders to clear the brain. lol

[perryg114]

Buttercup did this overcooling problem happen because you tried to increase airflow or was it like that to start with?

Perry

[Buttercup]

Originally Posted by perryg114

Buttercup did this overcooling problem happen because you tried to increase airflow or was it like that to start with?

Perry

It was like this from the start. In fact, I would guess that even the original fridge we had in this trailer had exactly the same problem.
I think it is perhaps a dynamic of the air flow around our TV that could be forcing extra air into the cooling path. Can't prove that but just suspect it could be happening. For now, our fridge is running perfectly - still.

[Aerowood]

Is your air inlet the type that goes through the floor?

[Buttercup]

No, it is outside air supplied to the grated access door. That is where I put the piece of MDF board to restrict airflow.

[LFC]

Have you checked the gas pressure ?

Mine was doing the same thing on gas and the regulator just needed adjusting.

You can also adjust the temperature up or down by sliding the little white cover up or down (it's next to the fins in the refrigerator) on Dometics without an adjustable temperature knob.

[Buttercup]

Oh yes, checked the gas pressure with my manometer at the regulator, at the fridge AND at the burner tip per Dometic's instructions and all were exactly as specified after some adjustment. Was not off enough to cause the problem and as always worked when we were steady, but quit going down the road.

[Buttercup]

I won the VAC Concours d'elegance award for best engineering feature for my thermalcouple system and fan modifications to my fridge.

[Aage]

Yay!! Well-deserved!

[perryg114]

Next time you need to do a 6 DOF test before getting a new unit. You know one of those transducer driven shaker table things like they test fighter jets on. I am sure they have an Airstream simulation you could use.

Perry

[Buttercup]

Ha, the roads in Minnesota are doing that for me now!!! Bumpy!

3 hours on the road, 40 degrees.

[Aage]

I am trying my hand at getting a "made in '88" RM2821 going, and first thing I checked was the 120V element, and guess what? It was D.O.A.

Anyways, I ordered a replacement online, and $60 including delivery to me here in Canada and I am keeping my fingers crossed that that's the end of the new parts needed!

Buttercup, I want to put ONE thermocouple in to see what is happening in there. My concern is the refer's performance in hot weather. Knowing what you know now, if you were limited to one thermocouple, which one would it be, and where would I find one of those?

[Buttercup]

Originally Posted by Aage

I am trying my hand at getting a "made in '88" RM2821 going, and first thing I checked was the 120V element, and guess what? It was D.O.A.

Anyways, I ordered a replacement online, and $60 including delivery to me here in Canada and I am keeping my fingers crossed that that's the end of the new parts needed!

Buttercup, I want to put ONE thermocouple in to see what is happening in there. My concern is the refer's performance in hot weather. Knowing what you know now, if you were limited to one thermocouple, which one would it be, and where would I find one of those?

One only would be tough for me! The 6 I have aren't enough!!! I could use 20 more. Hahaha.

That is a rough one because the value of having 6 is that they can be used relative to the others. Looking at one and comparing it to another really shows you so much more than one alone. For example, if you mounted it only at the inlet to the condenser, you could see the temperature coming into the condenser is high enough to still be in a vapor state, but you would really have to see the outlet temp then to get an idea that the condenser is really removing enough heat.

It's really tough to say. One isn't enough, really. I bought a cheap TC reader on eBay for $25 that came with 2 TCs. They were only 3 feet in length so, it's hard to place them where they can be of most use, around the condenser area in my opinion.

However, that being said, based only on what I know, it would help to know more about the hot weather performance issues. What is happening, what temperatures, is the AC running? Etc.... Your problem may just be a simple air flow issue as in not enough.

[KJRitchie]

What is your opinion of your new cooling unit performance compared to the one replaced? Does this Amish cooling unit live up to the hype?

We went out this past weekend. Up unit Sunday the temperatures in Dallas were close to 100F. My AS is in a back-in covered storage with electricity and I turned on the fridge a few days before departing. Despite being in the shade the temps inside were 99F, my indoor/outdoor thermostat indoor reading was pegged at 99F and with the fridge on 5 the reading was 44F. We didn't bother transporting food from the ice chest to the fridge until we got to the campsite. The campsite was in full sun but it was early evening and with the AC on and as the interior cooled the fridge started to recover and by the morning it was down to 32F. Being a weekend trip we didn't have much in the Dometic 3762 fridge. I deployed the curb, rear and street side awnings so for the most part the curb side of the trailer where the fridge had awning shade. The fridge was able to maintain about 37F at the hottest part of the day. We kept the ice chest inside the trailer for the beverages.

Keeping the inside of the trailer cool goes a long way to improving the fridge performance.

Kelvin

[Buttercup]

I don't think the Amish units have any greater performance abilities than any other units. They ALL have the same ingredients, water, hydrogen, ammonia and rust inhibitors. Maybe the amount of ammonia is varied in the Amish units or maybe they have a little more hydrogen - I don't know. The only way to really tell would be to test them side by side with identical calibrated test rigs to see if they have differing temperature drops from an identical thermal input.

I suspect the differences would be minimal in a side by side comparison.

Here is what I do know, running a bypass test on your unit on electric will show its capability. I cooled our fridge into the teens easily with both units, the new one was a little faster, but that could be a function of differing ambient conditions. In my opinion, I believe that with these units, with proper heat input and adequate heat removal at the condenser, they should work, even in fairly hot climates. If it can cool to 13 at 70 degrees, it should be able to cool to 43 in a 100 degree day. Of course, that is just my opinion and I will have to test that with my unit on some really hot day.