Norcold refrigerator 2002 Sightseer

[RVer01]

Hi I am a new member and happy to be here. I am having an issue with my Norcold refrigerator in my 2002 Winnebago sightseer. When the Motorhome is started it puts high voltage to the refrigerator which causes it to go into lockout mode. This only happens when Motorhome is running. Appreciate any help. Thanks in advance. ..Kevin.

[Morich]

Two points which may help to have more info.
One is what level is the high voltage? Is it the normal output for the engine alternator or something different?
That could lead to looking at the chassis parts versus the frig parts?
One or the other is not playing fair, so thinking of which is my first thought.

Second part is that frigs get changed out, so letting know what brand and model of frig is a start to looking for clues in troubleshooting manuals.

Not trying to be picky but needing to look at cutting the chase between looking at chassis problems versus frig problems? Posting up what year, model and floorplan you have will aid in going to the correct drawings. 27C or 30B?

Anything added or changes made like solar, lithium batteries, etc?

[RVer01]

Thank you so much for your reply. Sorry for the lack of info. New to the forum so please bear with me. I have a 2002 Winnebago Sightseer 27c which has a Norcold refrigerator, model number N621F. The refrigerator will run fine on shore power but gets voltage spike when engine is running. Not sure of the actual readings as it is in an rv repair shop. I am getting information from service manager. When voltage spikes it causes the refrigerator to go in lockdown mode with the n error code on the display and has to be reset. So far control board has been replaced but didn't solve the issue. Now wondering if it could be caused by faulty solenoid in the system. Not up much on the electrical side of things. Nothing new has been added to the Motorhome such as solar panels
Seems to just have happened overnight. Getting frustrating and very expensive. Any help greatly appreciated.

[Morich]

Thanks for the added info as it helps to see what might be happening! But it also brings some questions about the spike.
I define a spike as a sudden increase in the voltage to past some limit which makes the frig shut down to avoid damage. that is often something like a lightning strike or really strong.

But the batteries can't make a spike. They are just storage for what the rest of the systems produce. the alternator is what produces the voltage when it is running but that is where things get awkward as engine alternators on cars and trucks are not famous for spikes as much as they are for having a slipping fan belt that makes them turn slower and give lower voltage than we need!

I would not expect it to be the solenoid as it only operates to connect the coach battery and the chassis batteries together and can't make any higher voltage than what the batteries have in them plus the alternator. So if you have a battery at 12.5 and one at 13 plus the alternator running as fast as it can, the top voltage should never be over 13.5- 14 volts! But the frig should never shut down on those levels as it is normal for the alternator to put out that higher voltage until it gets all the batteries charged and then it cuts back slowly to avoid overcharging them to boil them dry!

This is where things begin to get even worse?
The manual for your frig is here:
https://norcold.com/wp-content/uploa...-21-06-n62.pdf

Dropping down to page 17 to look at the error codes show this:


Sorry but it seems that is as far as we can go and I might suggest calling Norcold for advise before trusting the repair folks too far???

[Ray,IN]

Monitor the 12V system at the engine alternator lugs while someone else starts the engine. The alternator voltage regulator can be failing; which can be replaced separately and for much less money. Norcold N 621, 12V limits are 10.6-15.4 VDC, outside those limits you get an error message.
reference: Norcold N 621 service manual

[RVer01]

Originally Posted by Morich

Thanks for the added info as it helps to see what might be happening! But it also brings some questions about the spike.
I define a spike as a sudden increase in the voltage to past some limit which makes the frig shut down to avoid damage. that is often something like a lightning strike or really strong.

But the batteries can't make a spike. They are just storage for what the rest of the systems produce. the alternator is what produces the voltage when it is running but that is where things get awkward as engine alternators on cars and trucks are not famous for spikes as much as they are for having a slipping fan belt that makes them turn slower and give lower voltage than we need!

I would not expect it to be the solenoid as it only operates to connect the coach battery and the chassis batteries together and can't make any higher voltage than what the batteries have in them plus the alternator. So if you have a battery at 12.5 and one at 13 plus the alternator running as fast as it can, the top voltage should never be over 13.5- 14 volts! But the frig should never shut down on those levels as it is normal for the alternator to put out that higher voltage until it gets all the batteries charged and then it cuts back slowly to avoid overcharging them to boil them dry!

This is where things begin to get even worse?
The manual for your frig is here:
https://norcold.com/wp-content/uploa...-21-06-n62.pdf

Dropping down to page 17 to look at the error codes show this:
Attachment 187212

Sorry but it seems that is as far as we can go and I might suggest calling Norcold for advise before trusting the repair folks too far???

Thank you again for your reply. I really appreciate any help. I did find a number for Norcold customer service and will try that on Monday. Thanks again.

[RVer01]

Originally Posted by Ray,IN

Monitor the 12V system at the engine alternator lugs while someone else starts the engine. The alternator voltage regulator can be failing; which can be replaced separately and for much less money. Norcold N 621, 12V limits are 10.6-15.4 VDC, outside those limits you get an error message.
reference: Norcold N 621 service manual

Thank you for your reply. I will definitely suggest this to the RV tech on Monday as they are not in the shop on weekends. I appreciate any help. Have a great day.

[prafersno]

You use the term Voltage Spike. Is it truly an increase in voltage or a large momentary AMP draw?

The only thing in the system that can spike Voltage is the regulator in the alternator. But that shouldn't make it into the 12V house system.

If your unit is a 3-way, there is an AC heating element and a 12V heating element.

Did they ohm the 12V element to make sure it is not shorted/burned out?

Will it operate on the house batteries?
Is it only when the engine is started/running?

Typically, the house batteries and the chassis (engine start/run) batterie(s) are pretty much separate other than a charging circuit from the chassis to the house batteries. Some have a solenoid that momentarily connects both systems to boost starting amps but that shouldn't factor here.

[Morich]

Originally Posted by prafersno

You use the term Voltage Spike. Is it truly an increase in voltage or a large momentary AMP draw?

The only thing in the system that can spike Voltage is the regulator in the alternator. But that shouldn't make it into the 12V house system.

If your unit is a 3-way, there is an AC heating element and a 12V heating element.

Did they ohm the 12V element to make sure it is not shorted/burned out?

Will it operate on the house batteries?
Is it only when the engine is started/running?

Typically, the house batteries and the chassis (engine start/run) batterie(s) are pretty much separate other than a charging circuit from the chassis to the house batteries. Some have a solenoid that momentarily connects both systems to boost starting amps but that shouldn't factor here.

Small point on the solenoid mentioned is that the two battery grooups are connected by the solenoid in two ways. One as mentioned is momentary for a jump start, however they are also connected full time when the ignition is on like when engine is running.

That would seem to leave an alterntor reg that is failing as a suspect. One good item to have on hand is not likely to be in the normal Auto shop, however. But a recording meter for voltage would let them spot any sudden peaks.
But what I see so many times in RV repair is that they deal with such a wide range of different issues from chassis to coach and everything in between that they are rarely really good at anything but changing parts!

So when they run into anything unusual like this seems to be, they really are not qualified to do much real study on the problem. The person with the right mindset, attitude and training to do things like change tires and do grease jobs is rarely the same guy who does indepth Air conditioning or electronics.

Just too much for any one person to have indepth knowledge on all the different phases if the shop is not so large that they have different sections within the group!

At that point, I consider moving to talking to the folks who build that specific part as they are likely to have the full story far better than folks who deal with EVERYTHING!

[RVer01]

Originally Posted by Morich

Small point on the solenoid mentioned is that the two battery grooups are connected by the solenoid in two ways. One as mentioned is momentary for a jump start, however they are also connected full time when the ignition is on like when engine is running.

That would seem to leave an alterntor reg that is failing as a suspect. One good item to have on hand is not likely to be in the normal Auto shop, however. But a recording meter for voltage would let them spot any sudden peaks.
But what I see so many times in RV repair is that they deal with such a wide range of different issues from chassis to coach and everything in between that they are rarely really good at anything but changing parts!

So when they run into anything unusual like this seems to be, they really are not qualified to do much real study on the problem. The person with the right mindset, attitude and training to do things like change tires and do grease jobs is rarely the same guy who does indepth Air conditioning or electronics.

Just too much for any one person to have indepth knowledge on all the different phases if the shop is not so large that they have different sections within the group!

At that point, I consider moving to talking to the folks who build that specific part as they are likely to have the full story far better than folks who deal with EVERYTHING!

Thank you for your input. It is truly appreciated. It is definitely as you described in a lot of rv shops. Troubleshooting electrical issues is a problem in most cases. I will also do as you suggested and seek assistance from Norcold customer service. Thanks again.

[Sightseer 27]

You should be able to manually select the refrigerator to run on "automatic" which seeks to run on 110volts, Propane only and 110V only.
You can see what happens when Propane only is selected.
You can check to see if there is a defect in the 110V heating rod which may help you see where this "excess" voltage is coming from.
Normally 12Volt devices are "downstream" from the batteries and thus sort of buffered from odd voltage "spikes"- all but the extreme spikes.
Over-voltage from a vehicles charging system should be easily detected with a starting of the engine at night as interior lights will/would quickly become overly bright- if you don't have a meter.
If the batteries are not up to the starting task by being old or poor connections, the voltage "dip"- being dragged down by starter current below 9Volts, can cause a false in the trouble code system.
Good Luck.
SS

[BobC]

I'm really suspicious about the tech using the term "spike" and would push him on the subject. The control board has been replaced which should eliminate most internal causes and, as Sightseer 27 mentions, other "spikes" are rare.

If I wasn't confident I could do it myself, I'd check with several other shops. Preferably I'd find an independent RV tech. I think you know enough about the problem now to ask questions to determine their knowledge level.

[Bobn1957]

Another thing to look at with the alternator is if one or two of the diodes has failed the alternator could inject AC current into the system, easy to check with a voltmeter set to AC volts! (there shouldn't be any AC)

[RVer01]

Originally Posted by Bobn1957

Another thing to look at with the alternator is if one or two of the diodes has failed the alternator could inject AC current into the system, easy to check with a voltmeter set to AC volts! (there shouldn't be any AC)

Thank you for your help. Any input is greatly appreciated.

[lowroller]

Just FYI, on you tube if you search " the Norcold guy", he is an expert on the systems. He helped me get mine fired up and running.