Norcold 1200 Preventative Maintenance

if it is not too late, I would go residential. best thing I have ever done in my coach

Most of the switches I have seen fail just stay open. I see no reason to install one in parallel as a back up. Since you are using fans with solar you already have some back up. I would just replace the snap switch with a new one and not try to fix what is not broken. As for a fan inside, yes they really help. They make battery operated ones that run for weeks. If you are a part time camper they work well. Easy to pop the batteries out when not in use.

dougrainer wrote:

YC 1 wrote:
Doug, it was a dinosaur board and not an original. We are not positive it was going into the defrost mode. That was suggested by the factory person but did not attempt to prove it ourselves. Resetting the board seemed to cure the problem temporarily. My friend is in their rv on my property visiting and would find the temperatures raising what appeared to be ever day at about the same time. Could have been coincidence but without a real schematic for the thing I had little information to work with.

Seems that having the fans and cooling system shut off when the doors are opened is really adding another failure point in the system as in this case due to an intermittent relay.

The purpose of shutting down the cooling system when doors are open is IF you are not there and the doors are open and it would be futile to have the refer continue cooling when it CANNOT due to the doors open. Logical to me. Doug

Doug, I'm totally with you on the why they designed it that way. It just seems a bit silly. I'm an ET with 40 yrs experience working on many things that have/had interlocks. You can't get two technicians to agree on how to install a connector let alone argue with an engineer that has never been in the field. :@

Do the 130 degree fan switches normally fail in the open or closed position? I have an extra so I mounted it beside the other one & will hook it up in parallel if they always fail in the open position. Otherwise will just dangle the wires for future use. It is a Pines Amish unit, they claim to need just one fan & since I had four I used two on battery power & two on solar with interchangable wiring. It's easy to pull the reefer out but a PITA if it is full.

What are the thoughts on installing fans inside the refrigerator to eliminate cold spots?

I also had an extra icemaker. It was easy to replace the tray which was delaminating so now I have an extra motor.:B

Mexicowanderer, wasn't it you that suggested Harbor Freight battery chargers for bringing batteries back to life. Holy cow, have you seen their price increases for the chargers & in general? Wow!

YC 1 wrote:
Doug, it was a dinosaur board and not an original. We are not positive it was going into the defrost mode. That was suggested by the factory person but did not attempt to prove it ourselves. Resetting the board seemed to cure the problem temporarily. My friend is in their rv on my property visiting and would find the temperatures raising what appeared to be ever day at about the same time. Could have been coincidence but without a real schematic for the thing I had little information to work with.

Seems that having the fans and cooling system shut off when the doors are opened is really adding another failure point in the system as in this case due to an intermittent relay.

The purpose of shutting down the cooling system when doors are open is IF you are not there and the doors are open and it would be futile to have the refer continue cooling when it CANNOT due to the doors open. Logical to me. Doug

I used to connect avalanche rectifiers across the 120vac heater element and clamp inductive spikes to 250vac when the heater element failed under load. The newer replacement boards probably already have this.

Doug, it was a dinosaur board and not an original. We are not positive it was going into the defrost mode. That was suggested by the factory person but did not attempt to prove it ourselves. Resetting the board seemed to cure the problem temporarily. My friend is in their rv on my property visiting and would find the temperatures raising what appeared to be ever day at about the same time. Could have been coincidence but without a real schematic for the thing I had little information to work with.

Seems that having the fans and cooling system shut off when the doors are opened is really adding another failure point in the system as in this case due to an intermittent relay.

YC 1 wrote:
If it is old enough to need a cooling unit why not replace the antiquated control board as well. Just spent a week on and off helping my friend chase the bugs out of his. The original one has some small relays that became intermittent.

The fans were also controlled by the doors as well. The cooling fans "when running" would shut off when the door was opened. The new board does not control it that way.

Here are the things we changed to repair his unit. Replaced the thermostat inside the refer. Added a switch to bypass the snap control device that is attached to the cooling fins on the top of the refer just below the vent. This allows the fan to run anytime we wanted. The fan running full time keeps the refer about 10 degrees cooler when on.

His board was intermittently going into a "defrost mode" and would need to be reset. One of the reasons for replacing it.

We ordered a lower temperature snap control device and will install it lower in the refer for convenience and use the wires that we ran to the new switch. This puts the two snap devices in parallel but that doesn't matter. The old one is designed for 135 degrees. The new one will come on at just over 100 degrees.

His vent tube did not have any device on the end to prevent air from entering so we just put a lot of water in the drip cup to cover the end for now.I suspect the previous owner removed it. I suggested he just extend the tube a few inches and curve it up so a small amount of water remains in the tube.

The refer has the recall board installed but the ground it uses is clipped to the water control valve assembly which is grounded through two screws and a couple of plastic stand offs. If the screws were to corrode the ground could be lost and the refer would not run. I found several tired grounds so cleaned them and in the case of this wire I added a wire and grounded it with some other wires that have their own dedicated screw.

Hope this is not too confusing.

Had it been mine, well a new residential would be sitting in its place. More room, newer technology, reliable, won't burn down.

1. IF you used a Norcold replacement board, then the doors do indeed shut the fans off. Norcold has NOT changed that on their boards. Not just the fans, but the cooling system shuts off also if the door switch is open. This prevents the refer from cooling if the doors are open which would be a waste.
2. HOW did you know it was going into defrost incorrectly?????? The defrost is evry 48 to 54 hours and ONLY does this if left on continously and there is no indication when the refer goes into defrost other than the rv'er happening on the refer NOT on for that 2 hours. Of course, how would you know if it was in defrost or just shut off because it reached temp? How would you know it needed to be reset. Reset is only for a NO CO condition. Doug

Hi,

I used a lighted switch so I know that there is power to the circuit. When I switch off the light goes off.

Here is a link to the protection device I mentioned: http://rvcoolingunit.com/ARP-RV-Refrigerator-Failure-Protection-Unit--C342739.aspx?sid=298

Jim Bryant recommends them and I have ordered one.

If it is old enough to need a cooling unit why not replace the antiquated control board as well. Just spent a week on and off helping my friend chase the bugs out of his. The original one has some small relays that became intermittent.

The fans were also controlled by the doors as well. The cooling fans "when running" would shut off when the door was opened. The new board does not control it that way.

Here are the things we changed to repair his unit. Replaced the thermostat inside the refer. Added a switch to bypass the snap control device that is attached to the cooling fins on the top of the refer just below the vent. This allows the fan to run anytime we wanted. The fan running full time keeps the refer about 10 degrees cooler when on.

His board was intermittently going into a "defrost mode" and would need to be reset. One of the reasons for replacing it.

We ordered a lower temperature snap control device and will install it lower in the refer for convenience and use the wires that we ran to the new switch. This puts the two snap devices in parallel but that doesn't matter. The old one is designed for 135 degrees. The new one will come on at just over 100 degrees.

His vent tube did not have any device on the end to prevent air from entering so we just put a lot of water in the drip cup to cover the end for now.I suspect the previous owner removed it. I suggested he just extend the tube a few inches and curve it up so a small amount of water remains in the tube.

The refer has the recall board installed but the ground it uses is clipped to the water control valve assembly which is grounded through two screws and a couple of plastic stand offs. If the screws were to corrode the ground could be lost and the refer would not run. I found several tired grounds so cleaned them and in the case of this wire I added a wire and grounded it with some other wires that have their own dedicated screw.

Hope this is not too confusing.

Had it been mine, well a new residential would be sitting in its place. More room, newer technology, reliable, won't burn down.