Norcold N822 Power Board

[NeilV]

Has anyone tried repairing the power board or found a more economical replacement board for the Norecold N822 unit?

I just went through the diagnostic procedure and the ignitor and all else checks out fine however after the burner lights it continues to spark and then times out going to shutdown with a flame sense error. The Norecold part is $256 at the local dealer while the Dinosaur Board equivalent for the Norcold N series refridgerators (6212xxx) is about the same.

Everything works fine on electric. I have not pulled the board yet to inspect it so I do not know what the conditions are like under the cover.

I just don't want to spend close to $300 to start repairing a 9 year old refridgerator when a new 2-way Norecold N841 can be had for $999 and the 3-way for only a few dollars more.

["007"]

Have you cleaned off carbon build up on flame sensor? If your burner is lighting the sensor may be dirty and needs to be cleaned or replaced. That part, SENSOR, is alot cheaper than board.

[RV Wizard]

I would second the replacing of the igniter. I have seen where they would ignite the burner but not sense the flame and send a good signal back to the board. There is no way to diagnose but to try a new igniter. Good luck and keep us posted.

[NeilV]

Quote:

Originally Posted by "007" Have you cleaned off carbon build up on flame sensor? If your burner is lighting the sensor may be dirty and needs to be cleaned or replaced. That part, SENSOR, is alot cheaper than board.

007 and Rv Wizard,

The N822 uses the ignitor to sense the flame. Both the ignitor and the burner have been made clean and shiney.

Norecold trouble shooting for the ignitor is to test the lead and ignitor for continuity (with an internal break in the lead or ignitor the spark would jump the gap but no feedback on the flame would be returned) and then verify that there is not a short to ground (bad/dirty insulator). The ignitor passes on both accounts.

I am replacing the ignitor anyway and will put that in first to see what happens before ordering the board. If it works I will be plesantly surprised but while hoping for the best I am still preparing for the worst.

Thanks for the input!

[NeilV]

Mike,

I replaced the ignitor and it was a no go. Burner still lights and shuts down with a no flame sense error.

Removed the burner to better polish it, blew out the tube and gently blew out the orifice after a quick light spritz with carb cleaner. Replaced and it was still a no go. Flame is a bit better and the igniter more quickly turns a cherry red.

Removed the power board, blew it off (it was surprisingly clean) and inspected it for bad/overheated solders/componets, broken traces etc and found none. Cleaned all connectors including the fuses and replaced but still a no go.

Ran a ground wire from the burner attachment screw to the powerboard ground screw just in case and still no go.

Took a well insulated screw driver and provided a secondary ground plane for the arc off the ignitor and got a flame sense. Now I am wondering if the crud that was in the burner pan may have been the other side of the arc instead of the burner itself. I have not found a good pictoral of this area on the N822. Any thoughts?

[RV Wizard]

Neil, the "ground plane" for the ignitor is the burner. Make certain that the surface of the burner is free of any carbon or rust. When I said that there is no way to diagnose, I was wrong in that there is a way to diagnose a broken or shorted igniter but I have seen some that checked ok with an Ohm meter but still would not function properly. The tip of the igniter/sensor should be in the blue part of the flame. It is the flame that produces millivolts the board needs to see to verify a fire on the burner. If a new igniter, clean burner and good connections a certain then you have a bad board and I would recommend the Dinosaur brand with a three year warranty over the OEM board.

[NeilV]

Mike,

The ignitor is new, you can see your reflection in the burner now and the connections are all solid.

Of course I need a board, the N822 takes the most expensive one so what else would it be. :O

Three things that nag at me are the three relays on the board that you can't easily remove the covers from. Probably a contactor in one of them with a bit of smutz on it.

Thanks,

[RV Wizard]

Neil, if you want and know of an electronics repair company, you could probably get them to replace the relays (all of them) for less than the cost of a new board. I would think though that the culprit is probably going to be more on the line of an IC or diode that has taken a spike or surge. Hey, this reminds me of something I ran across one time! Have you tried this with out the coach being plugged in or the generator running?

[NeilV]

Quote:

Originally Posted by RV Wizard Neil, if you want and know of an electronics repair company, you could probably get them to replace the relays (all of them) for less than the cost of a new board. I would think though that the culprit is probably going to be more on the line of an IC or diode that has taken a spike or surge. Hey, this reminds me of something I ran across one time! Have you tried this with out the coach being plugged in or the generator running?

I may go to Chester Supply and replace them myself. It would probably be on of the 12 volt micro relays near the high tension unit if it is the culprit.

The first thing I tried was charging up the new batteries and then running straight off them but that did not work. The batteries had just failed one month out of warranty so I was hoping it was just the bad bats dragging everything down. They were not using water or low just went bad.

[RV Wizard]

The reason I ask, is that one time we had a unit that would not operate and come to find out we had dirty DC from the converter charger that effected the Dometic Ref. board. We replaced the converter and that fixed the problem.

[NeilV]

Quote:

Originally Posted by RV Wizard The reason I ask, is that one time we had a unit that would not operate and come to find out we had dirty DC from the converter charger that effected the Dometic Ref. board. We replaced the converter and that fixed the problem.

Mike,

Understood that and it was one of the first things that I checked for.

To my thinking it will be the mechanical things that will gather resistence first along with the ignition coil which is what the flame sense is read through now that the ignitor itself is used to provide the flame sense feed back.

Got to get my electronics gear from my HeathKit days out of moth balls. Wish I still had that ocillascope sitting in the closet as it makes it easier to see how clean the sine wave form of a DC converter really is. It was really handy back in the day making your own DC power supplies. I guess it is one of those things that you really don't have a use for until after you let it go.

[RV Wizard]

Neil, you are so right about not needing a certain thing until the day after you get rid of it! It looks like you have covered all the bases and a new or rebuilt board is needed. Let us know how it is resolved. Stay safe my friend.

[NeilV]

Mike,

Bit the bullet and bought a 6212XX Dinosaur Board from ASAP. A friend (retired electrical engineer) was going to help trouble shoot the old board but he has not been well with respiratory problems so I decided no to expose him to soldering fumes etc. A barbeque party at the beach to test out the new board will make him just as happy and will get us both some bonus points with our wives. Came to $224.34 delivered to my door.

http://www.partsfortechs.com/asapcar...271-p-872.html


Only one jumper to set and it took about 15 minutes to install as basically a direct replacment for the original 621267 Norcold board.

Fired right up and no more faults.

One thing that I did prefer with the 621267 board is that the display panel showed a persistant display of what mode the system was in AC or LP when running on Auto select while the Dino Board only shows this information at the moment it makes the determination to select a particular mode and then just displays that it is using the Auto select option. Power management shows a 2 amp increase when the fridge is on AC power.

Sorry, but I am glad I did not have to pay a tech to do this for me. The cost of the board would have been well over $300 and the labor probably equal. Combined with what time I spent trouble shooting I have less time invested in this repair then it would have taken to arrange for service and drop off the coach. Hopefully not that many are like me an there is enough work to keep you busy and in groceries.

Regards,