It's six degrees in our freezer.
That's definitely the "top headline" at our house today. You see, it's been awhile since that's happened. We've been watching freezer temps fluctuate from zero to 70 for the last month. Today's steady single digits are definitely better. Much better!
Now that our Norcold refrigerator is back in the "safe zone", we can offer a brief summary of what we've learned over the last month. The first thing we learned was there is a bunch of misinformation out there. We're not claiming to be experts by any means. We're just a couple of RVers who have spent the last month dealing with a problem with one fridge and finally reaching a solution. By recapping our recent experience, we hope this information helps any fellow owners of "no"cold Norcolds that may pass this way.
Got Ammonia?
That's the first question to ask and answer when your Norcold loses its cool. If you see or smell this yellow liquid leaking from your fridge, your cooling unit (aka, the most expensive part of your refrigerator) is toast and needs to be replaced. If there's no sign of ammonia, the good news is your cooling unit might be OK. The bad news is you get to do some time-consuming trial-and-error troubleshooting.
Time and Temperature
These are the essential tools to troubleshooting your troublesome fridge. Gas absorption refrigeration is a slooooooow process. With every test you need to give the fridge plenty of time (like 24 hours) to "stabilize" and reach its best possible temperature. Of course, you need to be able to effectively monitor the temperature inside the fridge, ideally without opening any doors. We placed the outdoor sensor for our indoor-outdoor thermometer in the freezer and placed a "mercury" thermometer on the shelf near the fins in the fridge.
Got Air?
Gas absorption refrigerators need air to work. So, the first thing to check is that you fridge is getting all the air it can. Open your vents and check behind and above your fridge and in your flue and around your fans to make sure the flow of air is unrestricted.
Got Heat?
It takes heat for your fridge to keep its cool. Set the fridge temp on its highest setting and locate the "burner" on the back of your fridge. The area should be warm and any surfaces near the burner should be hot to touch. (They can be extrememely hot.) Run this test with the fridge set on "electric" and then on "gas". If you have no heat on either source, chances are your cooling unit needs to replaced. If you have heat with either or both, it's time to do some serious testing.
Pull The Thermistor
The thermistor is the thing that tells your fridge when to turn on and off. On our Norcold, it's a wire that runs from the light in the ceiling of the fridge to a clip on one of the fins in the back of the inside of the fridge. When you set the thermostat on its highest setting and remove the thermistor, you put the fridge in "emergency cooling mode". Give the box 24 hours of undisturbed cooling time. If temps are in the safe zone, your cooling unit is working. But, something else isn't. The first thing to replace is the thermistor. For about 20 bucks you can replace this part yourself. (No tools required!) After you've installed the new thermistor, give the fridge another 24 hours and check. If all is well, great! If not, it's time to check the control board.
Control Board
The control board is the "brains" of the cooling operation. It takes commands from the thermistor and tells the cooling unit how to work. We called on professionals we trust to test our control board. It failed the test. Replacing the control board is easy, but not exactly cheap. The ticket for our job was nearly $400. (Thanks to our extended warranty, our cost was $250.)
Cooling Unit
We gave our Norcold 24 hours to stabilize after the new control board was installed, and on a cool September morning in Kansas the freezer was the warmest spot in our house! With that, the evidence was clear. Our cooling unit, which had been dying a slow death, was gone. The most likely cause of death was a blockage of crystallized ammonia. It probably moved around awhile, which explained the fridge's off-and-on performance. With the blockage in its final resting place, it was time to replace the cooling unit.
At this point in our refrigeration adventure, we considered a couple of options. The first was what is known as the "Amish Cooling Unit". This aftermarket cooling unit is reported to be of better quality and have significantly higher performance than the Norcold. It's on backorder for weeks, plus we weren't exactly sure our extended warranty would cover a non-OEM replacement of this $2000 part. The second option we briefly considered was replacing our Norcold with a residential-style refrigerator.
This is an individual decision, to be sure. We opted to replace the cooling unit with another Norcold. There may be a residential fridge in our moose's future. But, for now, this was the quickest and easiest way for us to obtain the six degrees of refrigeration we were so desperately longing.
The new cooling unit arrived in a couple of days. (We spent those days in the good company of friends Sandy, John and Koko, who made a stopover at Melvern Lake en route to their new winter home in Arizona. They provided a most welcome distraction from our not so cool problem. It was great to see them!) Back at the repair facility, it took just a couple of hours for a couple of techs to slide out the fridge, place it face down on the floor of the moose, remove the old unit off the back, install the replacement and slide it back in.
Now that we have replaced the thermistor, control board and cooling unit, the "guts" of our Norcold are brand new. One of our techs pointed out that the only remaining part that could cause any trouble is the icemaker motor. ("Bite your tongue!" was my response to that little ditty.)
With handshakes with the trusty techs and a tip of the hat to our extended warranty company, we made our way late yesterday to another beautiful COE park at Clinton Lake, just a few miles from one of favorite towns: Lawrence, Kansas. We're looking forward to enjoying a few days getting reacquainted with our old college town.
Meanwhile, our new and improved Norcold will just be chillin'. In fact, I just heard the icemaker dump. What a wonderful sound!