Refer power question

[Jay & Bobbie]

2018, 345RL residential refrigerator
After several weeks with the shore power disconnected, now the refrigerator does not run when shore power is restored. It does, however run when the inverter is activated. I tried a master reset on the refrigerator with no change. I checked the GFCI in the bathroom, all good. Power is good everywhere but the refrigerator. How do I diagnose this issue (hopefully without pulling the refrigerator out).

 

[LeftOverParts]

We have a resi fridge in our ‘21 33231CK and it only works via the inverter (Progressive Dynamics CSW-2012) and the inverter has to be manually turned on. Ours also has a breaker for it in the breaker/fuse box that’s labeled, Inverter. If you have one, maybe it’s tripped.

Edit to clarify manually turning it on: When we bring the trailer from storage and plug into shore power to load-up for a trip, we have to turn the inverter on (either at the inverter or at the remote switch in the control cabinet). When already plugged into shore power and we disconnect shore power, the inverter will stay on. We turn the inverter off before taking it back to storage.

 

[Jay & Bobbie]

Maybe to be more clear, the refrigerator runs when the inverter is on, connected to shore power or not. When I turn the inverter off (manually) while connected to shore power, the refrigerator goes off as well. It has never done that before. I do not understand how it can work using the inverter and not work when on shore (ac) power. I historically leave the camper hooked up to shore power year round with the refrigerator running (when not on the road) because we leave stuff in it. The inverter is turned on when on the road with the dc to dc charging system keeping the battery fully charged.

 

[LeftOverParts]

the refrigerator runs when the inverter is on, connected to shore power or not.

The inverter is always connected to the battery so if on shore power and shore power (SP) is removed, the inverter should run. But if left on battery power alone, the battery will eventually die, and the inverter will turn off. Without SP, if you’re charging the battery through the 7-way connector or your dc-dc charger, the inverter and fridge should stay running (unless your power draw is more than what the charging systems can supply and your battery
dies).

When I turn the inverter off (manually) while connected to shore power, the refrigerator goes off as well. It has never done that before.

This is exactly how ours works bc the fridge is only powered by the inverter. If you turn off the inverter, the power to the fridge is cut.

I historically leave the camper hooked up to shore power year round with the refrigerator running (when not on the road) because we leave stuff in it.

This should only be possible with the inverter on.

The way ours works, when we bring the trailer home from storage (or if we came home from a trip with the inverter off) we have to turn the inverter on after connecting SP. We don’t have an auto on system. If you do or had auto on, you might check your manual or contact the mfr.

 

[MandK]

Jay & Bobby, Our ‘21 had a transfer switch that plugs into the inverter. Your may be similar. It senses shore power and disconnects from the inverter, doesn’t matter if the inverter is on or off. If you have a transfer switch, it may be the problem. It’s Not sensing the shore power either because there is a switching problem inside or a wire connection problem from the shore power and is just staying switched to the inverter. This was the transfer switch in my Montana. Good luck.

 

[LeftOverParts]

Here’s a diagram of the entire chain.

MandK’s post has me wondering it my transfer switch is acting as it should bc what you describe re operation seems normal.

One more thing: Is your main battery disconnect switch on or off when you’re having the “never did that before issue”? Let’s say it’s on, does the issue resolve if you turn the switch off. Or vice versa.

 

[DutchmenSport]

I agree, it's the transfer switch.

 

[Jay & Bobbie]

Yes, the transfer switch has a blown component. Thanks to all for assistance. I did not know what that was and how it worked. Makes sense now. A new one will be ordered.

 

[rickybobby]

Don't those transfer switches have a fuse internally that an be replaced? It's possible that has a blown fuse

 

[Jay & Bobbie]

I double checked.
Some sort of transistor exploded. New one installed today. It is working as expected.

 

[rickybobby]

Perfect, glad to hear you got it fixed without purchasing a new transfer switch