Norcold not cooling on A/C.

[Boehler]

Need some help with my Norcold RV refrigerator. It seems to cool OK on gas, but won't run on 110A/C. AC is supposed to be the default, but it stays on gas operation only. I have confirmed that there is power at the outlet at the back side if the unit and that the plug is firmly seated.

I don't know what else to do. Any suggestions?

 

[jgillott]

Does your's have the 3 way mode...gas only, AC only, and Auto?

 

[Boehler]

It has gas and AC. It is supposed to switch automatically to AC if it is available. This one stays on gas only.

 

[jgillott]

That is the way that mine is supposed to work when set to auto. I've had trouble a couple of times where it wouldn't move from auto gas to auto AC when I plugged it in. When I changed the mode to AC only, it worked fine.

Let me snoop around on another forum I belong to and see if I can find anything over there.

 

[Learjet]

you can check the resistance on the heating element or see if it is open.

 

[jgillott]

you can check the resistance on the heating element or see if it is open.

That seems to be the general idea of where to start in the treads I've read on other forums. If the fridge is otherwise working on gas, it has to be heating element related. It could be the element itself, control, or power supply issue.

 

[DavidC]

Model # ?

Dave

 

[Tuesdak]

This site has some troubleshooting info:

https://www.arprv.com/norcold-ac-heater.php

Service manuals... http://bryantrv.com/docs.html

 

[Boehler]

Norcold NVFLT

 

[Boehler]

I got out multimeter this morning and started checking. 120 volts at the outlet, good. Looked at circuit board, AC fuse zero resistance, good. Checked resistance across the leads to the AC heater, close to zero ohms, bad!

Looks like I need to find a new heater element, and figure out how to swap it out.

 

[SnoKing]

Wait one!!! The heating element should look like almost a dead short with very low resistance.

Ohms law E=IR, where E in voltage, I is current and R is resistance. So in this case we can use E/I=R, with E=120V

If it draws 5 amps it would be 24 ohms
If it draws 10 amps it would be 12 ohms

Should be in that range 12-24 ohms or there abouts.

On edit: The question is does it not go into the AC mode or does it not cool when the AC only mode is selected?

SnoKing

 

[Boehler]

I went out and double checked. I removed the wires from the control board, and measured the resistance between them. the ohm meter showed 00.1. Virtually a complete short. I was hoping to see something like 40 to 60.

 

[MarkEagleUSA]

I went out and double checked. I removed the wires from the control board, and measured the resistance between them. the ohm meter showed 00.1. Virtually a complete short. I was hoping to see something like 40 to 60.

Wouldn't 00.1 indicate an open condition? The element should show resistance if it was good.

 

[SnoKing]

I went out and double checked. I removed the wires from the control board, and measured the resistance between them. the ohm meter showed 00.1. Virtually a complete short. I was hoping to see something like 40 to 60.

Well that should have blown a fuse or cause something on the circuit card to burn up, unless it can sense a short and not turn on. Are things really rusted on the back side of the frig. A guy across from us just had a new cooling unit installed because the heating element was rusted in place and would not come out. Very expensive! He should have just converted to a residential frig.

SnoKing

 

[SnoKing]

Wouldn't 00.1 indicate an open condition? The element should show resistance if it was good.

00.1 is a dead short not an open.

 

[DavidC]

Very expensive! He should have just converted to a residential frig.

SnoKing

Residential is ok if your always going to have shore power or generator. Running one on an inverter and batteries is going to kill batteries quickly. Just my opinion but I would like the gas backup.

Dave

 

[DavidC]

I went out and double checked. I removed the wires from the control board, and measured the resistance between them. the ohm meter showed 00.1. Virtually a complete short. I was hoping to see something like 40 to 60.

Find the element, unplug and test. If the wiring is shorted it would also give you that reading.

Dave

 

[B.G. Smith]

What setting did you have the meter on?

 

[Boehler]

Duh!!!! Of course it is a short! Sometimes my 70 year old brain slips into neutral.

The back side doesn't look rusty at all. The control panel on the front only shows gas operation. Doesn't shoe trying to operate on AC. Doesn't show any trouble codes.

 

[Boehler]

What setting did you have the meter on?

Meter was set at Ohms 200K