RV Products 9000 series A/C troubleshooting

Used the 3326 last weekend. This being FL, the A/C ran hard all weekend but cycled normally with only an occasional tweak of the thermostat dial to keep the temps in range. The last evening, I noticed the trailer was getting colder and colder, and the compressor would not cycle regardless of the temp setting.

The manuals I have for the RV Products 9000 series A/C units does not show an exploded parts diagram, so it is unclear if the thermostat is a circuit board or more likely a rheostat.

Has anyone suffered this type of failure? Are there any user serviceable parts inside related to temp control? I have a separate thermostat on the back of the dinette seat for the furnace, so unless I am missing something that should not be involved in the problem.

Thanks, Paul

[Wavery]

Originally Posted by MisterP

Used the 3326 last weekend. This being FL, the A/C ran hard all weekend but cycled normally with only an occasional tweak of the thermostat dial to keep the temps in range. The last evening, I noticed the trailer was getting colder and colder, and the compressor would not cycle regardless of the temp setting.

The manuals I have for the RV Products 9000 series A/C units does not show an exploded parts diagram, so it is unclear if the thermostat is a circuit board or more likely a rheostat.

Has anyone suffered this type of failure? Are there any user serviceable parts inside related to temp control? I have a separate thermostat on the back of the dinette seat for the furnace, so unless I am missing something that should not be involved in the problem.

Thanks, Paul

It sounds to me like your thermostat may have failed. I can assure you that it is not controlled by a rheostat. The compressor should shut-off when the thermostat reaches a minimum temperature setting. It should not come back on again until the temperature increases a few degrees (@ the thermostat location).

There is a starter unit in the AC that you can reach from the top. The cover is held on by a few screws. The starter is a black cylinder. I know this can fail and the compressor will not start, but I'm not sure if it can fail the other way. Easy to check.

[Wavery]

Originally Posted by terryh

There is a starter unit in the AC that you can reach from the top. The cover is held on by a few screws. The starter is a black cylinder. I know this can fail and the compressor will not start, but I'm not sure if it can fail the other way. Easy to check.

The starter has nothing to do with the compressor not shutting off. It could only be the thermostat, a crossed wire or circuit on the mainboard which is unlikely. It's sorta like if a light won't shut-off in a lamp, it could only be the switch.

At the beginning of last summer had same problem, replaced thermostat, fixed problem. Ordered part from dealer I bought my camper from. Install a little tricky but no worse than what I do every day of the week.

After some digging found the site below, includes parts and tech manuals for various Airxcel products:

http://www.rvcomfort.com/rvp/tech_info/parts_doc.php

The link to Airxcel does not seem to be working. That may be my internet connection. Has anyone had problems with the fan motor not blowing? Half way through a very warm humid stay in KC MO our A/C quit blowing. Replacing the fan motor only solved part of problem. It appears the capacitor is shot as well since it will not start with out a physical push of the blades. Is there any other items that I need to check to be sure the fan works properly. We also had a great deal of water dripping into the trailer during this trip any ideas on the cause of this?

The link is working.

I don't care if you post here, but you are asking for assistance with multiple issues that may not be seen in this thread. You might want to start a new thread with your questions. JMO.

I would replace the capacitor then determine if the problem with the fan continues. Seems like you already have stated what needs to be done.

You may wish to be more specific about where water is coming in - was it raining? Is it air conditioning condensate? There are a lot of potential causes but not enough info. to help.

Before I forget, the parts in the ceiling such as the thermostat are referenced by the ceiling fixture not by the A/C unit outside the trailer. You can find the model and serial numbers by removing the foam air cleaner diffuser and there is a tag inside there.

I have replaced the thermostat, we will see this weekend if the compressor cycles again.

[Bill]

Paul -

As I recall, there is a condensate drip pan of some kind built into the air conditioner, probably accessible from the outside. It occasionally happens that the outlet tube (tubes?) gets clogged up with debris of one kind or another - pollen, leaf litter, etc - and then the pan overflows into the interior of the trailer. Once you locate the tubes, it is easy to push a wire, and then a pipe cleaner through them to clear them out.

Spend a little time with the Search tool on this forum - this topic was discussed in a fair amount of detail a couple years back. Or cruise the AIRXCEL site, once you get connected to it. I believe you have the Polar Mach Low Profile 92XX series unit, and there is lots of documentation, including a detailed parts list and exploded diagram.

As for the fan? If it runs once you start it manually, then the fan capacitor is almost certainly the culprit - either bad or disconnected somehow. Again, the AIRXCEL docs will show you where it is and how to replace it. I'm sure you are aware that the fan capacitor is independent of the compressor's two capacitors.

You confused me a bit by saying

the trailer was getting colder and colder, and the compressor would not cycle regardless of the temp setting.

Did you mean that the compressor turned off, and would not turn on? (Which would be normal if it is cold in the room.) Or the compressor came on and would not turn off? (Probably what you meant.) For a number of simple reasons (really wet weather, clogged louvers or filters, misdirected airflow baffles - see the AIRXCEL site), it occasionally happens that the cooling coil freezes over completely with ice. And then the unit does weird things. Since air cannot circulate, the coil's temperature sensor (not the same as the thermostat) may not know how cold or warm it is, and it thinks that the compressor should stay on. And ice formation could be aggravated by water thrashing around from an overflowing condensate drain pan. The solution is simply to turn the whole thing off and let it thaw out completely, and make sure the drip pan drains are clear. Waiting a week will probably have it running right again since the cooling coil will have thawed and the drain pan at least partially drained - but replacing the thermostat may have nothing to to do with it.

Good luck.

Bill