Both heaters fixed, now on to the Dometic rm-4804

February 18, 2019, 02:15:05 pm

Well both heaters are now working (just in time for summer) So now I am on the refrigerator. Question-I took the cooling unit out but do not see any yellow from leakage. Can it leak and leave no sign of leakage? With the ac powering it you can hear a gurgle but no cooling. Blockage? Would like to keep the refrigerator as it has the ice maker and a Long Island Ice tea needs ice! Plus it has a "step" to it's foot print that may make it hard to install a new refrigerator.

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #1 – February 18, 2019, 02:21:26 pm

Be aware that absorption refrigerator cool down MUCH slower than compressor-driven refrigerators.

Check after 24 hours and check on 120 VAC as well as propane.

BUT, keep a close eye on it, as a discharged cooling unit can over-heat to the point of starting a fire.

And, yes, the ammonia can leak out and not leave a yellow trace that you can see. Depends on where the leak is and whether microscopic or large enough for the larger molecules to escape.

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #2 – February 18, 2019, 02:58:25 pm

Quote from: unknown – February 18, 2019, 02:15:05 pm

1.With the ac powering it you can hear a gurgle but no cooling.
2. Blockage?

1.Where do you hear the gurgling?
If it is gurgling there is some amount of ammonia/hydrogen left.
2. possible, depends a lot on #1

Mike

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #3 – February 18, 2019, 03:06:44 pm

Quote from: wolfe10 – February 18, 2019, 02:21:26 pm

Be aware that absorption refrigerator cool down MUCH slower than compressor-driven refrigerators.

Check after 24 hours and check on 120 VAC as well as propane.

BUT, keep a close eye on it, as a discharged cooling unit can over-heat to the point of starting a fire.

And, yes, the ammonia can leak out and not leave a yellow trace that you can see. Depends on where the leak is and whether microscopic or large enough for the larger molecules to escape.

I know that the ammonia/water cycle is slow to cool but after an hour I should feel some temp differences along the tubing. When it was all together I let it run for 36 hours and no cooling.

Quote from: Pamela & Mike – February 18, 2019, 02:58:25 pm

1.Where do you hear the gurgling?
If it is gurgling there is some amount of ammonia/hydrogen left.
2. possible, depends a lot on #1

Mike

I here it gurgle when I open the door. And I am leaving the ice maker off as it is a totally divorced system and has nothing to do with the refrigerator
.

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #4 – February 18, 2019, 03:46:19 pm

Gurgling would alarm me. Consider a new cooling unit from JC Refridgeration in Shipshawana.

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #5 – February 18, 2019, 04:22:33 pm

You took the cooling unit out??? What am I missing?

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #6 – February 18, 2019, 05:25:17 pm

Don't understand why anyone would keep a Dometic that is fire prone from the get go. We installed a Residential about 5 years ago and would never go back.

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #7 – February 18, 2019, 05:34:49 pm

Quote from: NancyS – February 18, 2019, 05:25:17 pm

n't understand why anyone would keep a Dometic that is fire prone from the get go. We installed a Residential about 5 years ago and would never go back.

My understanding is that the Norcolds were a hazard like the 1200 series. While true that the Dometic has a small chance of catching fire due to it being a water/ammonia cycle refrigerator (thank you Albert Einstein)I like the propane part as I do not always park were there is AC power.

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #8 – February 18, 2019, 05:36:45 pm

Without hesitation I would remove the entire old refrigerator and replace it with a residential unit. We are extremely happy with our Samsung 18 cu ft model.

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #9 – February 18, 2019, 05:37:49 pm

The 1988 OE unit does fix to the coach wall front , with many little screws. About 15in from the floor. MY resy install required a support Box , screwed to the floor and raising the new unit to the roof , fitting into the same upper part of the refer hole. I had to cut the lower grille area out and build a flat closeout panel , about 15x24.5 in wide.

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #10 – February 18, 2019, 05:41:14 pm

Quote from: Dakota Slim – February 18, 2019, 04:22:33 pm

You took the cooling unit out??? What am I missing?

Not much-I find it easy to handle the cooling unit by its self. If I found it to be ok it is only a little foam/metal tape and some mastic to put it back. But to me it would not be reliable as it could plug up again. So I ordered a new unit.

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #11 – February 18, 2019, 05:42:47 pm

Quote from: D.J. Osborn – February 18, 2019, 05:36:45 pm

Without hesitation I would remove the entire old refrigerator and replace it with a residential unit. We are extremely happy with our Samsung 18 cu ft model.

I often park were there is no ac power so I like the propane cooling.

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #12 – February 18, 2019, 05:56:32 pm

We used to lay the refer on its side for a day. Chris here did a lot of that.

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #13 – February 18, 2019, 06:05:46 pm

But, if the cooling unit is out, is partially or completely blocked, I totally agree-- REPLACE IT.

To replace your RM4804 with a newer absorption refrigerator requires removing the "hump" at the back of the refrigerator and building a new floor, trim off a little off one side and install a "drain through the basement for safety as the propane is now below the outside vent. No big deal. Did that in our 1993 and replaced it with a new Dometic 3962 Refrigerator.

Probably just slightly less work to install a residential refrigerator. But not a particularly good option of you do extended boondocking, as the U225 has limited battery capacity/weight capacity to carry additional batteries.

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #14 – February 18, 2019, 06:30:16 pm

I am going to replace the cooling unit and keep it as a 4804. No need to remove hump.

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #15 – February 18, 2019, 06:33:40 pm

Quote from: unknown – February 18, 2019, 06:30:16 pm

I am going to replace the cooling unit and keep it as a 4804. No need to remove hump.

If compressor unit working, a good choice.

Though the newer ones ARE larger capacity, as the "hump area" is now refrigerator.

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #16 – February 18, 2019, 07:26:30 pm

JC offers a 5 year guarantee on his replacement cooling units. Better than new.

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #17 – February 18, 2019, 07:30:58 pm

Quote from: unknown date=1550520404 link=msg=341802]
.I here it gurgle when I open the door. [/quote]
[quote author=unknown – February 18, 2019, 03:06:44 pm

550520404]

With it gurgling where you describe you made the best choice to replace the unit if you have the need for an absorption refrigerator in your style camping.

Mike

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #18 – February 18, 2019, 07:47:54 pm

Quote from: unknown – February 18, 2019, 05:41:14 pm

Not much-I find it easy to handle the cooling unit by its self. If I found it to be ok it is only a little foam/metal tape and some mastic to put it back. But to me it would not be reliable as it could plug up again. So I ordered a new unit.

Right, but how did you test it? Run 120v right to the AC heating element?

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #19 – February 18, 2019, 08:23:24 pm

Quote from: Dakota Slim – February 18, 2019, 07:47:54 pm

Right, but how did you test it? Run 120v right to the AC heating element?

First I let it do its thing for a day and a half on AC. would not stay on on propane. 12 volt dc did not cool at all. Then I took out cooling unit and ran straight 120 ac to the heater.

Re: Both heaters fixed, now on to the Dometic rm-4804

Reply #20 – February 18, 2019, 08:43:45 pm

[quote ait'suthor=Jeff & Sandy link=msg=341837 date=1550535990]
JC offers a 5 year guarantee on his replacement cooling units. Better than new.
[/quote]
True--but ours lasted barely 5 years--making me wonder if it was worth it. The new Samsung works so much better in every way that it's worth it to give up some boondocking capabilities in order to have such a nice refrigerator.

Affiliate Notice