Nor cold fridge won?t run on electric but works on gas

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.

Appleton54913

New member
Joined
Jul 23, 2018
Posts
4
Have a 2015 travel trailer and nor cold fridge won?t wrk on electric so it defaults to lp and works fine. I tested voltage going into the fridge power board and it tests fine at 120 volts. Buss fuse is good and tested terminals for 120 volts that go to heating element. Didn?t have anything. So I replaced the board and I still have no power going to heating element. Not sure what I?m missing. Please help
 

Gary RV_Wizard

Site Team
Joined
Feb 2, 2005
Posts
74,650
Location
At our Silver Springs FL home
Go back to that board and check the voltages again. The input 120v power goes through the fuse on the board and an on/off relay and direct from there to the heating element. Nothing magic happens in between - the power is either on or off.

The relay will stay in the off position until the thermocouple inside the fridge signals for cooling. When it does, the circuit board switches on the relay and power flows to the heater element. Power stays on until the thermocouple no longer calls for cooling.

You said the fridge defaults to LP cause the 120v doesn't work. That doesn't sound right. The fridge will stay in 120vAC mode as long as 120v is present at the circuit board. Whether the heater element is working or not.  To be best of my knowledge it won't auto-change to LP under those circumstances. It sounds to me like the board is not able to detect the 120v input, so it is defaulting to LP.
 

Back2PA

Well-known member
Joined
Jul 26, 2015
Posts
5,766
Gary RV_Wizard said:
It sounds to me like the board is not able to detect the 120v input, so it is defaulting to LP.


Using the diagnostic function of the panel you can see if the board thinks 120v is missing. The manual has a step by step procedure (at least this is true on the 1200)
 

Appleton54913

New member
Joined
Jul 23, 2018
Posts
4
Thanks everyone for your help. I appreciate it. And Gary I think you’re right. It doesn’t detect 120 so it goes to lp. It’s automatic. There’s a power button on the front of the fridge and that’s it. If it doesn’t see power after 5-10 seconds it looks for lp. Also you said it goes to a on/off relay before sending voltage to the heating coil. Is it possible that the relay is bad? If it’s part of the power board then it should all be replaced.  I guess I’m not sure why my board is not sensing 120 volts when it is supplied to it. I still test 120 to the power board and past the buss fuse but nothing out
 

Gary RV_Wizard

Site Team
Joined
Feb 2, 2005
Posts
74,650
Location
At our Silver Springs FL home
The on/off relay is part of the board, so yes it was replaced when you swapped boards. So was the 120v sense.  Given that, I don't see how a faulty relay of sense circuit could be the problem. 

I know you said you tested the 120v going into the board, but maybe you should revisit that. Make sure you are testing the right pairs of wires (120v in and 120v out to the heater) and that you are verifying voltage in the same way the circuit board sees it, i.e. relative to the terminals on the board.  NOTE: Only the 120v hot (black wire) actually flows through the circuit board components.  The incoming 120v neutral is jumpered direct to the neutral terminal for the heater at the board entry, so basically the neutral from the heater is wired direct to the neutral feed (white wire).  Make sure that path is solid. If the board and the heater don't have a solid neutral wire connection, nothing happens.
 

Gary RV_Wizard

Site Team
Joined
Feb 2, 2005
Posts
74,650
Location
At our Silver Springs FL home
The only service manual I know of for the N6xx models is this one:

http://bryantrv.com/docs2/docs/ncoldnnewnseries.pdf

Even if your eyebrow (control) panel looks a bit different, I believe the rest is still applicable to the vt1 version of the N611.
 

Alfa38User

Well-known member
Joined
Oct 4, 2007
Posts
6,678
There appears to be several 5 amp fuses on that board as there is on almost all other models boards. It could be that at least one is for 120V and it could very likely be blown. It may not be obvious visually but checking it using a meter or by substitution with a known good fuse may point out the problem.
 

Appleton54913

New member
Joined
Jul 23, 2018
Posts
4
Ok here is pic of my board. I have 120volts into the board. Checked many times with a volt meter. Buss fuse has continuity. It tests good. So I have 120 volts on the right side off buss fuse. Then it goes to that red thing, witch I?m assuming is the switch. There?s 120 volts at the top, but 0 at the bottom. I turn fridge off, then back on even giving it a few minutes in between, leaving the door open. The green light comes on and after z5 seconds it goes to Amber and starts on lp and runs perfectly. Just doesn?t sense power. Is there something that could be bad that senses the power? I?m still stumped. Can?t find the problem. Thanks
 

Attachments

  • C7BE5359-B99E-46FD-9A2D-FE32E2A273FB.jpeg
    C7BE5359-B99E-46FD-9A2D-FE32E2A273FB.jpeg
    168.4 KB · Views: 14

kdbgoat

Well-known member
Joined
Apr 16, 2014
Posts
6,313
You can pull the board out and take it to a dealer. They can test them, often for little to no charge.
 

cerd

Well-known member
Joined
May 29, 2018
Posts
621
Location
MN
I would also recommend to pick up a set of very sharp test probes that can pierce the insulation without leaving a big hole. On my fridge, I found a bunch of bad crimps that I had to redo to get it working. I haven't had an issue since.
 

chris_willigen

New member
Joined
Oct 5, 2021
Posts
1
Location
Canafa
Appleton did you ever figure out your problem. I am experiencing the same issue.. I have new boards and heater element and I can not get power past the red object to the element
 
Top Bottom