Refrigerator outlet not powered on battery

[sirving]

Refrigerator/freezer outlet is live on shore power but not live when disconnected and on battery, e.g. driving. It was working fine on a recent long trip. Now it is not.

Lithium battery is 100%. Fuse #6 circuit is fine. Other things on the same circuit (LP monitor and 2 USB ports) are working. GFCI switches are working. It is not the refrig itself as it works on shore power and when plugged into a different battery powered outlet. Not the outlet itself, as it works on shore power. It should not need the inverter, and off or on, it does not make a difference.

I am stumped and would appreciate any ideas. Thank you.

[PaulBristol]

Of course a 12 volt battery will not power a 120 volt refrigerator. It needs an inverter to convert the 12 volts DC to 120 volts AC. Smaller inverters are frequently only connected to a select set of 120 volt outlets.

In your RV, the refrigerator 120 volt outlet is not connected to the inverter.

Post make and model number of inverter or inverter/charger for better advice. Also post make and model of refrigerator.

[hikingcamera]

I think some clarifications are needed. It sounds to me like you have a two way refrigerator. If there is a two blade fuse like this:



Then it has a DC connection.

But you also keep referring to an outlet. In your Airstream coach, 120V AC outlets would be covered by circuit breakers that look like this:



Our fridge is DC only, but it sounds like yours might be a two way and can operate on DC and AC. Is that accurate?

You said you can plug it into another outlet, so does it have a standard 3-prong plug somewhere?

And does it have another set of wiring coming out of it that might be hard wired?

Is this a new to you Airstream coach? Or is this a problem that has just started?

This is just a guess, but it seems like there may be some issue with the DC wiring between your fridge and the 12V fuse.

[StogieMan]

The fridge/freezer on that build year can run off 12v or 120 AC. I’m not sure if you swapped out the inverter when lithium was installed and tied all the circuits to the inverter. If so, it should always run. The old inverter was not tied to that outlet so the inverter will not power it when not tied to shore power but the 12v should take over and work all the time unless you turn off the fridge or your batteries are drawn down.

If the fuse is working then the 12v connection probably got disconnected. You’re going to need to take a look in back of the fridge to see if it got disconnected and re-install it.

[sirving]

The fridge does run on 12v and 120V, as you said. The fridge plugs into an outlet that is in the pantry/closet and it is that outlet that is only live now on shore power, not 12 volt. I was looking for a mouse nest behind the refrig and perhaps I disconnected the inverter connection behind the fridge. Any guidance to what I should be looking for? Thanks so much for your response.

[hikingcamera]

Originally Posted by sirving

The fridge does run on 12v and 120V, as you said. The fridge plugs into an outlet that is in the pantry/closet and it is that outlet that is only live now on shore power, not 12 volt. I was looking for a mouse nest behind the refrig and perhaps I disconnected the inverter connection behind the fridge. Any guidance to what I should be looking for? Thanks so much for your response.

The outlet behind your fridge is AC only. The inverter will invert DC power to AC for that outlet when the inverter is turned on, but this is different than the fridge running off DC directly. Most RV-specific fridges are at least dual power. (Some RVs come with residential fridges that are AC only.)

The DC connection would not have an outlet, but would be hard-wired with perhaps an Anderson connection or some sort of pinned connection on the fridge for disconnecting the fridge from the wiring. This is separate from the three prong AC outlet, and would avoid the efficiency hit from inverting power from DC to AC (and likely back again to DC inside the fridge).

That said, if the fridge is only setup as a one way, and the outlet was previously inverted but no longer is, then yeah, there seems to be some issues with the inverter or wiring to the inverter.

[hikingcamera]

Originally Posted by hikingcamera

The outlet behind your fridge is AC only. The inverter will invert DC power to AC for that outlet when the inverter is turned on, but this is different than the fridge running off DC directly. Most RV-specific fridges are at least dual power. (Some RVs come with residential fridges that are AC only.)

EDIT:
Most RV-specific fridges have a direct DC connection (Some are dual or triple powered and can also be powered directly from AC or propane, and some RVs come with residential fridges that are AC only.)

[djb75]

Have you checked your fuses (as suggested by hikingcamera)?

[StogieMan]

Originally Posted by sirving

The fridge does run on 12v and 120V, as you said. The fridge plugs into an outlet that is in the pantry/closet and it is that outlet that is only live now on shore power, not 12 volt. I was looking for a mouse nest behind the refrig and perhaps I disconnected the inverter connection behind the fridge. Any guidance to what I should be looking for? Thanks so much for your response.

Ok, let’s back up a bit.

Do you still have the stock inverter or did you swap that out when you installed the lithium batteries? If you only switched out the batteries and not the inverter, that outlet is not an inverted outlet from the factory. It will not work and will only be powered from shore or generator power for 120 AC.

If you swapped out the inverter and then put either all the outlets or added the refrigerator outlet to the inverter, then that outlet will have power when not tied to shore/generator power.

The 12v connection to the fridge is at the back of it via a spade connector. Both the refrigerator and the freezer have their own 12v connection as they are separate units. Does your freezer work on 12v when not connected to shore power? If the freezer still works on 12v then something came loose in back of the refrigerator and you’re going to need to pull it out to check. If the freezer also does not work on 12v, then you’re going to have to pull that one out too and take a really good look at the wires. Both sets of 12v wires are ran together via a taped harness and their is a rats nest of wires under the freezer area where they come from the 12v panel. The 12v wires comes from you 12v distribution panel to the refrigerator and nowhere do those wires connect to the inverter.

In your initial post you mentioned that Fuse# 6 which also runs the fridge was fine but I would still pull it out and check it and make sure it goes back in the whole way. Sometimes they won’t go in all the way without a little persuasion.

Attached are some pictures of what the refrigerator/freezer connection look like, the 12v wires and the rats nest under the freezer. These were some older pics that I had before we replaced the fridge/freezer and cleaned up the wiring mess under there.