Cooling Unit Redux

I have known for quite some time now that our refrigerator was marginal. So it was a frequent topic of conversation between Wendy and I re: what to do about it – if anything? The freezer compartment was keeping things frozen and the bottom side was keeping things cool, but not as cold as it should be. Besides, it was just not getting the beer cold enough!

If you know me, you know I had already done the research online and knew there was a good possibility that the ‘new’ cooling unit that was installed just a couple of years ago was not ‘quite up to snuff’. I also found out that the factory built cooling units that you can buy from Norcold or Dometic were also questionable due to the fact that they had all been recalled at some point in the past. It seems that they can overheat and accidentally release hydrogen gas! Since RV refrigerators are absorption-type they require a high heat source to remove heat and thus cool the unit. How’s that for counter-intuitive? We all know that hydrogen and a high heat source like a propane flame are not good things to bring together… Rather than actually fix the problem, Norcold recalled their products and had RV service centers install a small circuit box that simply shuts the whole thing off if it gets too hot! In the software business, we called that a kludge, not a solution.

A couple of years back, I discovered that our Norcold refrigerator was subject to this recall and even though it was several years old, it had never been ‘fixed’. So I set up an appointment at Olathe Ford RV over in Gardner, KS as they were the local designated Norcold service center. Our reefer was old enough that the recall involved an entire new cooling unit and their kludge. To say the least, we were not impressed with Olathe Ford RV Service. Nevertheless, as far as I know, they did replace the cooling unit. The refrigerator never worked too well afterwards, but at least it won’t catch on fire.

Which brings us right back to the here and now (more or less) with a refrigerator that works, marginally, but not as well we’d like it to. The problem is it was still working, so there was no definitive problem – just a subjective notion that it should be better.

Now I’ve had to pull this monster out of its cabinet several times over the years in order to work on various projects and it is a bear of a job. I knew there were two electric muffin fans on the back of the cooling unit. The first thing to check according to the experts was to be sure those fans were running – no  fans, no cooling. However, you can’t see or touch those fans when the fridge is in position and I could not hear or feel any fans running. Since we were now living on the road, I was very reluctant to pull that refrigerator out in a WalMart parking lot or RV park just to see if the fans were running! Besides, what can I do about it anyway.

During my online research I found the RV Cooling Unit Warehouse web site also provided technical support as well as selling – you guessed it – new cooling units! I discovered that the Amish make replacement cooling units for most RV refrigerators! How the Amish got into that business is a mystery to me, but apparently their units are well designed and don’t catch fire and thus don’t require the kludge and they are much better performing units. They aren’t cheap, but then neither are the factory units that catch fire and still need the kludge. So I decided if we needed a new unit, I’d buy one of these Amish ones.

It just happens that Memphis, TN is the only place you can both buy these units and have them installed besides the factory in Shipshewana, IN. Other places can install them, but the units have to be shipped. As you can imagine shipping and receiving is a problem for us. So when we finished up on the Tanglefoot Trail, it only made sense to do the 80 miles or so to Memphis.

David Force is the expert at the RV Cooling Unit warehouse and according to the tech, David has been working on these RV refrigerators since the 60’s. He knows his stuff. David referred me to Ron at R&C Mobile RV Repair and before we headed north to Memphis I called Ron to see if he would take a look at our Norcold. So we pulled into Southaven RV Park just across the line from Memphis and set up camp.

Ron took a few temp readings in the freezer and refrigerator compartment and confirmed the high readings I was getting: 15 – 20 F in the freezer and mid-50’s F below. The freezer should be closer to 0 F and the bottom end more like 38 F. We weren’t close to that. It seemed to work better on AC than propane, but neither was optimal. The first thing Ron checked was the fans and he determined that they were not running – thus explaining in part the high temps.

IMG_6794

Ron checks the wiring.

The question was why weren’t the fans running? After checking several items he determined that the fan switch was defective so he bypassed the switch and the fans still wouldn’t run. That’s when he noticed the wiring problem. Now this one is not on me. I have never touched the wiring on that refrigerator. However, Ron found the fans had been wired backwards and consequently could never have worked! The only time that wiring had been touched was when Olathe Ford RV replaced the cooling unit. The only thing to do was hard-wire the fans and AC heating elements to run full-time and see if the cooling unit recovered. If the temps don’t go back down where they should be in a couple of days, then the cooling unit was most likely damaged from high heat resulting from the miswired fans. So we sat at the RV park for two days hoping for the best.

Two days later, the temps had come down some, but were still marginal especially considering the mild temperatures we were experiencing weather-wise. So, we decided to bite the bullet and replace the cooling unit. While we were at that, we’d also replace the fans and fan switch and AC heating elements.

It’s now late morning Monday and the KC Royals are scheduled to play Game 3 of the 2014 ALCS. We wanted this job wrapped before game time! Besides that we were under a tornado watch and severe thunderstorm warning for 3 pm. Ron assured us it could be done in time so he took off in his truck to get his helper, Jessiah, and a new Amish-built cooling unit from David Force. Wendy and I emptied the fridge and prepared the bus.

IMG_6793

Floor and cabinets protected as best we can.

The first task is to pull the doors, disconnect the wires and propane and get the beast out of the cabinet and out onto the floor of the bus. It weighs better than 200 lbs, so you need a good plan and a strong back. Ron has this great rolling furniture cart with a built-in jack that is perfect for this job – too bad we couldn’t use it! Our fridge is too close to the floor. Fortunately, I’d done this job alone several times and knew how to do it with 2×4’s, a blanket and a goodly supply of foul language! The trick is to keep it balanced upright and don’t let it drop all the way to the floor – you’ll never lift it back up. Having three of us didn’t hurt and we had it out in short order. To get the cooling unit out, you have to lay it on the floor backside up. It’s a messy job so we had the floor and cabinets well protected. We had to move  everything out of the salon to make room on the floor.

IMG_6797

Slowly sliding it out onto a couple of 2×4’s. The towel allows the whole assembly slide on the floor.

IMG_6798

Its out and we slide it across the floor.

IMG_6799

Ron and Jessiah lower it face down.

IMG_6802

The old new cooling unit exposed and ready to remove.

IMG_6804

and out

We discovered the old (new) cooling unit had been shoddily installed with the wrong type of sealant that allowed hot air to leak into the insulated compartments. Right about now, the rain starts in earnest and continues the rest of the afternoon. Fortunately, most of the outside work is done.

IMG_6809

All that old sealant had to be removed and the area cleaned and prepared for the new cooling unit.

IMG_6810

This is the back side of those fins you see on the inside of your RV refrigerator.

IMG_6811

Ron preps the area with thermal mastic and spray foam just prior to installing the new cooling unit.

IMG_6789

The new cooling unit.

IMG_6812

The new cooling unit just prior to installation. Note the foam and thermal mastic in the recessed area of the refrigerator back.

A refrigerator is just a heat transfer device. In the picture above, those thin tubes on the cooling unit have to contact the  metal plates on the back of freezer and refrigerator compartment in order for that heat transfer to take place. The thermal mastic ensures good contact and the foam seals the area from other heat sources.

IMG_6813

Ready for installation.

IMG_6814

The new unit is in place.

Nothing left but to attach the new fans, install the propane burner, rewire and put it all back in place. Getting that beast back in the cabinet was much harder than taking it out as it is a very tight fit. If I ever have to do this again I’ll take a saw to the cabinet so this part of the job is easier. We had it all done just about the time it quit raining. We think the full rainbow was a good omen.

DSC_0767a

 

Advertisements

4 comments on “Cooling Unit Redux

  1. Oh Wendy and Jim – what a ordeal with the refrigerator! You cannot imagine how much I admire you two. Betsy (and Ralph) Holliday

  2. I still have our Amish refridgerator in the bus. I keep it in the bays and lift the lid and throw in a bag of ice if we don’t have power lol

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s