Dometic RMD 8555 Refrigerator replacement

[stevejones]

Our 2019 GT has the Dometic RMD 8555 refrigerator in it. The initial refrigerator performed so poorly that Airstream finally replaced it under warranty last August. Now the "new" one is performing poorly.

Have any of you replaced your refrigerator with a different model? What brand/model did you pick and how has it performed?

Thanks,

Steve

[jeffmc306]

Steve, we have the same Globetrotter / fridge.

If ours dies I’d consider the 12V/120V unit Airstream is now using. It’s more efficient in all temps and has a deeper interior because it doesn’t have the ammonia heating unit. I haven’t checked the dimensions but would guess it would fit in the same opening.

GMFL has the new 12V in his 30’ GT and really likes how it works (his is larger).

Let us know what you decide to do!
Jeff

[lewster]

I can't say enough about the 12V/120V units. I have replaced many in Airstreams and they all work very well. some are not direct replacements though and will need some top and side trim re-done, but overall they are much better than their gas/absorption cousins. Nothing like a real fridge compressor over those gas/absorption units.

[GetawA-S]

I agree with Lewster. We have not owned an installed compressor fridge, just a portable that we bought to supplement our propane fridge on hot days. The “icebox” pulls about 40 W when cooling, and runs about 25% of the time in our house, so about the total consumption is 20 Ah/day (for all you boondockers). That’s twice or three times what a propane unit pulls when running on gas, about 1/4 of the same propane unit on electric. I’m sure an installed, larger, compressor fridge uses somewhat more, but the efficiency is there. And it COOLS regardless of conditions outside!
When our last trailer’s fridge was giving us fits, I googled the common makes and compared cutout sizes to what was listed for the existing Dometic. It was not hard to find a fit. (We limped along and upgraded the trailer, wishing the ‘20 23FB we bought had the NovaKool, but the current Dometic is not such a dog as the one in the ‘19 22 Sport.)
Most appliance suppliers have a contact number that will get you through to an applications engineer who can help. You still need to blank out the vent openings, but it seems like a very doable switch.
Keep cool!

[buckshot99]

I'm on my 3rd fridge in my 2020 GT27. Hoping this one will last. I wanted the one they are putting in the new units as well but they have to redo the cabinet.Let us know what you end up doing.

Stay Safe!

[GCinSC2]

Steve,

Any particulars on what this fridge is or isn't doing?

Gary

[stevejones]

Originally Posted by lewster

I can't say enough about the 12V/120V units. I have replaced many in Airstreams and they all work very well. some are not direct replacements though and will need some top and side trim re-done, but overall they are much better than their gas/absorption cousins. Nothing like a real fridge compressor over those gas/absorption units.

Lew, how well do these units perform off the battery when boondocking or dry camping? You may recall installing my solar system Spring of 2019 so I should have plenty of battery.

I believe the NovaKool RFU6800 should fit in the same space pretty well. This is the unit they are putting in the 25 foot Globetrotter now. It has basically the same interior capacity.

Thanks,

Stegve

[stevejones]

Originally Posted by GCinSC2

Steve,

Any particulars on what this fridge is or isn't doing?

Gary

Gary, it does not cool well. Inside temps in the 40s. Freezer is not cold enough. Everyone that has this model that I have talked to has had problems and every RV manufacturer that installed it in their RVs has quit using it (including Airstream). The forums for those RVs are full of complaints for this fridge. I think Dometic has now discontinued it. It is just a bad design for some reason.

Steve

[Downhill502]

Have you tried relocating the thermistor? With its current location, right on the cooling fins, makes it think the overall interior temperature is colder than it actually is. This is a common mod and I can show you the location of ours as it has been wonderful since the relocation. Ours was preforming poorly prior as many have stated. Also make sure your heat sink/condenser fan is functioning properly on warm days, located in the outside service compartment.

[GCinSC2]

Steve,

Fridge frustration, no clue if anything in here Service Manual and Service Instructions https://myrvworks.com/wp-content/upl...ice-Manual.pdf can help you but can't hurt to put this link in this thread. https://myrvworks.com/wp-content/upl...structions.pdf

These are courtesy of Darren at My RV Works.

I've chased a fridge butterfly a couple times.

Gary

[lewster]

Originally Posted by stevejones

Lew, how well do these units perform off the battery when boondocking or dry camping? You may recall installing my solar system Spring of 2019 so I should have plenty of battery.

I believe the NovaKool RFU6800 should fit in the same space pretty well. This is the unit they are putting in the 25 foot Globetrotter now. It has basically the same interior capacity.

Thanks,

Stegve

Hi Steve,

They typically draw around 6 amps per hour, so they draw around 130 amps /24 hours. This should be no problem with your system considering it's solar and battery capacities.

[lewster]

Toasterlife,

It depends of course on what you have for back-up. If you have a complete solar charge system with lithium batteries, then a Vitrifrigo (or similar) compressor fridge should last just about as long as you boondock.

[stevejones]

Originally Posted by lewster

Hi Steve,

They typically draw around 6 amps per hour, so they draw around 130 amps /24 hours. This should be no problem with your system considering it's solar and battery capacities.

Thanks Lew, hope things are going well and you are well down there in Naples.

Steve

[stevejones]

Originally Posted by Downhill502

Have you tried relocating the thermistor? With its current location, right on the cooling fins, makes it think the overall interior temperature is colder than it actually is. This is a common mod and I can show you the location of ours as it has been wonderful since the relocation. Ours was preforming poorly prior as many have stated. Also make sure your heat sink/condenser fan is functioning properly on warm days, located in the outside service compartment.

I have not. I know this was done by the Airstream Factory Service Center to the refer in a friend's 2019 GT 27 but his improvement was marginal.

A picture or description of where yours is and info on how you affixed it would be welcome. Couldn't hurt to try.

Thanks,

Steve

[SpinWhite]

Originally Posted by Downhill502

Have you tried relocating the thermistor? With its current location, right on the cooling fins, makes it think the overall interior temperature is colder than it actually is. This is a common mod and I can show you the location of ours as it has been wonderful since the relocation. Ours was preforming poorly prior as many have stated. Also make sure your heat sink/condenser fan is functioning properly on warm days, located in the outside service compartment.

Could you take pictures to show us the change you made?

[Downhill502]

Originally Posted by SpinWhite

Could you take pictures to show us the change you made?

Of course! I will take a picture tomorrow.

[GCinSC2]

Just being curious I looked at both manuals I posted links to. Looks like Thermistor is now referred to as Temperature Sensor NTC.

The Service Manual doc on page 38 shows its location as built and page 49 shows temp vs resistance data and which terminals on the board to take the measurement at.

[Downhill502]

Keep in mind you may have to alter the exact location of your thermistor closer or farther from the evaporator fins to get the temperature control you are after. The thermistor is a resistance based temperature sensor so I’m sure the manual has just updated the wording to temp sensor. The other photo shows the location of the cooling fan that turn on with warmer ambient/operating temperatures.

[GoBlueBird]

I also have a 2019 GT that had fridge cooling problems. However, I am a retired engineer, who did work in thermal management, so I looked for the issue. For mine, the thermal grease behind the fins did not align with the cooling coils, so there was poor heat transfer and low cooling efficiency. I cleaned up the mess and installed new thermal grease that completely covered the black tubes. Since then, I have had no problems with the performance (over 100 nights) in all types of weather.

[GCinSC2]

GoBlueBird

Sounds like that deserves its own thread with pics. That bond is shown in cooling unit R&R but good possible solution if missing.

Gary