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jholder's avatar
jholder
Explorer
Jul 11, 2023

Norcold 811 fridge not working on A/C

I had a guy hook up a 30amp plug at my place the other day and when I plugged my RV into it, I found the AC wasn't working. He apparently made a mistake and reversed the neutral and hot wires in the box. Once he swapped them all seemed to work fine, except for the fridge...

The fridge was running off of A/C power through a standard 120v outlet but when I switched and plugged into the 30amp it switched over to gas. Since then it will not work on A/C power.

I checked the breakers on the main RV panel and none were tripped, and all fuses there were good. I checked the exterior panel covering the fridge and found the 8amp glass fuse was blown. Thinking this was the issue I replaced it, although I couldn't locate an 8amp and I replaced it with a 7.5amp, but still no A/C power. It did not blow the 7.5amp fuse, and then 5 amp blade fuse on the board is still good as well.

Any thoughts on what I should check next? I'm wondering if it couldn't have fried something on the board itself although there is nothing visible.

Thanks for any assistance!

7 Replies

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  • wnjj's avatar
    wnjj
    Explorer II
    Jul 12, 2023
    If you have the cover off the control board, check for 120V across the AC_HT (LO/HI) pins where the electric element plugs in while the fridge is on in AC mode. If you don't have 120V there and the 8 (7.5A) fuse is still good you may have a bad AC relay. If you do have 120V on those pins and the fridge still isn't cooling, you may have a bad electric element. You can test that with a ohm meter with the power OFF by measuring ohms across the same AC_HT terminals. It should measure ~40-50ohms.

    The AC side is fairly simple with the power cord coming in routing one terminal direct and the other terminal through the fuse and relay to the heat element.

    Our 621 model fridge intermittently failed on AC 5 years ago. I fixed it with a $2 relay replacement. https://www.rv.net/forum/index.cfm/fuseaction/thread/tid/29727778.cfm

    Service manual for your fridge here if it helps: https://norcold.com/wp-content/uploads/2021/09/OM_N61N81_635485D_20210902.pdf
  • jholder's avatar
    jholder
    Explorer
    Jul 12, 2023
    Gottahaveit wrote:
    It's a long shot but once our fridge would not work on A/C and the GFCI plug in the bathroom was tripped.


    Thanks. I checked all my outlets and all are working with nothing tripped. I do have power at the fridge 120 outlet.
  • jholder's avatar
    jholder
    Explorer
    Jul 12, 2023
    dougrainer wrote:
    Are talking you had a 30 amp plug installed or a 50 amp? Reverse polarity should NOT have blown the refer 120 volt fuse. BUT, you need to check for 120 on EACH SIDE of that 7.5 amp fuse. Use ground for 1 probe and the other on each side of the spades while the fuse is plugged in. Make sure the refer power cord is correctly installed on the control board and snug. Doug


    It is a 30 amp plug. I wouldn't have thought that reverse polarity would blow that fuse either but that's when it happened, as I know it was working just minutes before plugging into the new outlet. Nothing else seems to have been affected oddly enough.

    The power cord is all good, but I will check both sides of the fuse.

    Thanks for your input.
  • Gottahaveit's avatar
    Gottahaveit
    Moderator
    Jul 12, 2023
    It's a long shot but once our fridge would not work on A/C and the GFCI plug in the bathroom was tripped.
  • dougrainer's avatar
    dougrainer
    Nomad
    Jul 11, 2023
    Are talking you had a 30 amp plug installed or a 50 amp? Reverse polarity should NOT have blown the refer 120 volt fuse. BUT, you need to check for 120 on EACH SIDE of that 7.5 amp fuse. Use ground for 1 probe and the other on each side of the spades while the fuse is plugged in. Make sure the refer power cord is correctly installed on the control board and snug. Doug
  • jholder's avatar
    jholder
    Explorer
    Jul 11, 2023
    opnspaces wrote:
    Get a multimeter or a small 120 volt item (radio, fan, table lamp etc) and plug into the 120v outlet in the refrigerator compartment. Is there power at that outlet?


    Good suggestion I should have tried that. But, yes, I just checked and there is power to the outlet it plugs into.
  • opnspaces's avatar
    opnspaces
    Navigator II
    Jul 11, 2023
    Get a multimeter or a small 120 volt item (radio, fan, table lamp etc) and plug into the 120v outlet in the refrigerator compartment. Is there power at that outlet?

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