Hello all, John here.
Today was Air Conditioner Day! I was all excited yesterday when my parts arrived from RV Products, the makers of the Basement Air unit. First I want to say how awesome RVP is to work with for parts and service. Plus they shipped really quickly, and parts were reasonable. The reason I decided we needed to pull the unit for maintenance is that we have been having cooling issues for quite a while.
I thought most of it was just the unbearable weather here, but in reality, I now think a lot of it was related to the lack of maintenance on the unit. Recently it has started the freeze up, where the airflow would be cut off, and the compressors would just drown on attempting to compress gas, that wasn’t expanding because the airflow wasn’t allowing it to. I narrowed the problems down to a couple possibilities. One, the Evaporator coil was plugged, or Secondly if could be a low freon problem. i didn’t think it was low freon because when it was blowing it was blowing cold. Another symptom was that it would keep running even after it was frozen, which it is supposed to shut the compressors down at that point and let the evaporator thaw. I was pretty sure at least one of the thermistors was bad.
I’ll be honest in that this was at first a really daunting task, I thought at first it would be quite difficult to remove the unit to work on it. Luckily from the inter webs I found this PDF file written by “Duner” or Bill Elsenpeter, and posted on RV Forum, which has become my latest Favorite RV discussion board. Anyhow, Bill walks you through the Removal and Reinstall on a Workhorse Chassis Winnie, but mine was very similar to his procedure, and certainly a project anyone with basic skills can handle.
The only real difference is how it is mounted in. My outlet duct was the same as Bill’s example, and as with his you do not need to disconnect any wiring. There is Just enough to pull the unit out and turn it 90 degrees to the coach to work on it. The hold “down/in” was a little different, as on my chassis, Winnie used the top rail as the upper restraint, and mounted the unit on a tray, that is held up with 2 1/2 inch bolts about 4 inches long. All you need to do is to crank them down and apply some pressure to the bottom face of the unit as you are doing that, and it should drop right out. I was able to pull it out myself, though I would not recommend doing it that way because the unit is fairly heavy, awkward, and unbalanced as the compressors are both on one side, and those are the heavy parts. Regardless, I got it out and on my makeshift stand of two 5 gallon buckets and 2 4 ft. 2×6’s.
Right away I saw the problem. The evaporator coil was plugged almost completely. Almost a 1/2 inch of dust, hair and ick matted into a sticky felt like substance. No doubt compiling itself for the past 8 years. I wonder how any airflow got through it at all… Here’s a pic…
After getting it out, and balanced on the buckets, I pulled the top off. All 28 screws. What did we do before the Cordless Drill? I quickly got the two thermistors changed out, and also the “Pillow” blocks, or Fan bearing on both of the fans. Many people have had problems with the bearing wearing out, but mine actually looked decent. Yes, some wear, but not worn out. I figured I had the parts I might as well change them. I almost took “Duners” advice and went with Ball Bearing replacements from Grainger, and may do that the next time I pull this unit, but really I don’t see it as necessary at this point. If mine were wore badly, I might think differently. I then proceeded to clean it up, hose out the coil, and use the Evap Cleaner I got at Grainger yesterday. I do like the foaming cleaner, as it sprays on “Liquid” so you can get it in all the fins, and then it foams up nicely and expands out the dirt. It took me about 4 times before it was clean enough. I then rinsed it well, and did the condenser too.
All squeaky clean, I grabbed a plastic fork and spent a good hour straightening fins out, buttoned it up and ran it for a while. I called Derek to ask him to come home from lunch and help me put it back in. It slipped back in pretty smoothly. So time to check the results! It was truely amazing the difference it made! First, the airflow is 10 times more, and you can actually tell a difference when the fan on the high or low setting. I ran a cooling check and found the air temp differential to be 23.5 degrees, measured at the intake, an then at the first exhaust port, when I tested it my outside thermometer read 83 degrees. I also checked amp draw on the motors and fans, all which were right within spec.
Taking away from this, I can say I am no longer “afraid” of this unit, as RVP is awesome at support, and R&R really isn’t that bad. I had the whole project wrapped up in less than 5 hours, and I was screwing around making sure everything was just so. Furthermore, I think this needs to become a regular project, at least every other year living full-time, and more likely annually. I also learned that if I can pull it out, getting the unit charged is not overly costly, and any home A/C guy can do it. Overall, a good project done, and certainly glad it is done!
Now off to bask in my new jets of cold air!
Have a good night! John