Forum Discussion

Leatherneck2093's avatar
Leatherneck2093
Explorer
Jul 24, 2020

Dometic 4 door 12cuft fridge not getting below 40 degrees

We bought very rarely used like new 2019 Grand Design Reflection 28bh. We are on our maiden voyage check out trip. The dometic 4 door 12 cuft fridge, which is in a slide out, is set to 5 and doesn’t want to cool below 40. The freezer stays between 12-17 degrees. I can hear fans on the back of the fridge running from time to time. I don't see the thermistor clip on the inside fins that I can adjust. Daytime temps are running 90-96. We are in a nicely shaded spot so the fridge doesn’t see direct sun.

I have noticed that the cabinet around the fridge is really warm. That tells me that its not insulated and a lot of the heat from the cooling unit coil is filling that void. Is insulating that void around he body of the fridge something that would adversely affect its operation or would that be a good thing to do?

There is a baffle in the top vent that covers 2/3’s of the vent cover. That doesn’t make a lot of since to me either.

I tried searching for this but wasn’t successful.

Any help or direction to a previous thread would be greatly appreciated.
  • Leatherneck2093's avatar
    Leatherneck2093
    Explorer
    Jul 25, 2020
    Garry&Gayle wrote:
    I had the same panel covering half the top vent on our Dometic RM1350 of which I cut to allow full vent flow. I then installed a 3rd fan in the back centered just above the factory fans along with triple vent fans inside, the thermistor should be on the left side wire is not very long. My fridge will run around 37 degs. and freezer is at 10 deg in 95 deg. heat. The eyebrow temp says 33-34 degs. the inside room temp will effect them also, try and keep below 80 deg. if possible.
    Dometic told me not to add insulation to the very top of refer they need that air space.


    Thanks Doug.
  • Leatherneck2093's avatar
    Leatherneck2093
    Explorer
    Jul 25, 2020
    Garry&Gayle wrote:
    I had the same panel covering half the top vent on our Dometic RM1350 of which I cut to allow full vent flow. I then installed a 3rd fan in the back centered just above the factory fans along with triple vent fans inside, the thermistor should be on the left side wire is not very long. My fridge will run around 37 degs. and freezer is at 10 deg in 95 deg. heat. The eyebrow temp says 33-34 degs. the inside room temp will effect them also, try and keep below 80 deg. if possible.
    Dometic told me not to add insulation to the very top of refer they need that air space.


    Thanks for the info. I am able to keep our Reflection 28bh at 71 degrees easily with the 15k btu and the 13.5k btu AC’s. Was your baffle metal? If so how did you cut it?

    I arranged my drain line to have a trap in it today and restarted the fridge at noon so the 2 hour defrost will happen in the middle of the night now. Don’t know how much affect that will have but why not. Every little bit helps.
  • Garry_Gayle's avatar
    Garry_Gayle
    Explorer
    Jul 25, 2020
    I had the same panel covering half the top vent on our Dometic RM1350 of which I cut to allow full vent flow. I then installed a 3rd fan in the back centered just above the factory fans along with triple vent fans inside, the thermistor should be on the left side wire is not very long. My fridge will run around 37 degs. and freezer is at 10 deg in 95 deg. heat. The eyebrow temp says 33-34 degs. the inside room temp will effect them also, try and keep below 80 deg. if possible.
    Dometic told me not to add insulation to the very top of refer they need that air space.
  • dougrainer's avatar
    dougrainer
    Nomad
    Jul 24, 2020
    Leatherneck2093 wrote:
    Lwiddis wrote:
    Temporarily try a battery operated fan in the fresh food compartment. Dry ice too. Then warranty service.


    I installed a triple fin fan unit inside now I’m considering additional valterra fans outside in the top vent.


    Bingo, Refers in slide rooms need an additional fan blowing OUT that upper door to cool correctly. OEM's never install that needed fan. Install that fan and you will be amazed at the better cooling. Doug
  • Leatherneck2093's avatar
    Leatherneck2093
    Explorer
    Jul 24, 2020
    Lwiddis wrote:
    Temporarily try a battery operated fan in the fresh food compartment. Dry ice too. Then warranty service.


    I installed a triple fin fan unit inside now I’m considering additional valterra fans outside in the top vent.
  • Leatherneck2093's avatar
    Leatherneck2093
    Explorer
    Jul 24, 2020
    valhalla360 wrote:
    Does it have difficulty getting to 40F or does it get to 40F no problem but doesn't want to go lower?

    40F is generally the recommended fridge temp, so it may be the thermostat limiting is set to 40F.

    Of course those are hot conditions and if you are opening the door to check, absorption fridges don't recover as quickly after you let warm air in.

    The freezer is a little warmer than the recommended 0F but other than ice cream not being rock hard, shouldn't be a major issue.


    It seems to maintain between 39-41 but has run at 34-37. I have a triple fin fan unit in it now. The USDA says 40 is a max temp for safe food storage.

    We keep our drinks in a 12v 54qt compressor freezer/fridge and our small fridge in our outdoor kitchen. This limits getting into the big fridge to meal times twice a day.
  • Leatherneck2093's avatar
    Leatherneck2093
    Explorer
    Jul 24, 2020
    Second Chance wrote:
    There are several threads on this topic over on one of the two Grand Design forums (I forget which one). They specifically mention that baffle. Here are the two forums:

    My Grand RV

    Grand Design Owners Forum

    IIRC, the threads are in the GD Owners forums.

    Rob


    Thanks a lot.
  • valhalla360's avatar
    valhalla360
    Navigator
    Jul 24, 2020
    Does it have difficulty getting to 40F or does it get to 40F no problem but doesn't want to go lower?

    40F is generally the recommended fridge temp, so it may be the thermostat limiting is set to 40F.

    Of course those are hot conditions and if you are opening the door to check, absorption fridges don't recover as quickly after you let warm air in.

    The freezer is a little warmer than the recommended 0F but other than ice cream not being rock hard, shouldn't be a major issue.
  • Lwiddis's avatar
    Lwiddis
    Explorer II
    Jul 24, 2020
    Temporarily try a battery operated fan in the fresh food compartment. Dry ice too. Then warranty service.

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