A/C doesn’t turn off when reaching set temp

[JesPasnThru]

I think I have original equipment in my ‘05 Cougar 285 with a Dometic Duo-therm Brisk Air using a handheld Dometic Remote Comfort Control (IR0101). When I set the desired temp and start the unit using the remote, it doesn’t turn off the a/c when it reaches that temp.

Any ideas on what might be wrong?

Has anyone changed out this kind of infrared handheld remote for a digital wall unit?

[flybouy]

When you say it doesn’t “turn off” when it reaches that temp do you mean the compressor and fan don’t shut off or does the compressor shut off but the fan continues to run?

[JesPasnThru]

Neither of them shut off. I listened for the compressor to kick off but it doesn’t happen. The room temp, as indicated on the handheld remote, dropped 2 degrees below the target temp on the remote. Fan and comp were still going for several minutes, then I shut it off.

[JesPasnThru]

I’m also wondering if anyone knows about changing from an IR remote to a digital wall thermostat. There is a controller on the ceiling right next to the a/c that over-rides the remote in the event it become lost or has dead batts.

Would I use the wire that exists for that ceiling controller to attach a digital thermostat and just ditch the remote? Looks like a phone cable that plugs into side of main controller inside the a/c unit. But I understand the polarity is opposite of a phone cable. I think.
I’ve seen vids of changing from analog to digital, but none that go from IR remote to digital thermostat.

[LewisB]

Neither of them shut off. I listened for the compressor to kick off but it doesn’t happen. The room temp, as indicated on the handheld remote, dropped 2 degrees below the target temp on the remote. Fan and comp were still going for several minutes, then I shut it off.

I'm wondering if your test was a little quick - do you know what the span is on your remote? (It may be 3 degrees, for example) You probably need to turn this on and get some broader testing in place. You might find it actually will cycle, but at a less precise temperature. Also, are you holding the remote in your hand or setting it on a counter?

Most AC controls allow for "high", "low", or "auto" operation. In ether high or low, the fan will continue to run at all times and the compressor will cycle based on temperature. It may be very hard to hear the compressor cycling - on ours, if there is any other noise, it is almost impossible to hear the compressor. Best test is to get an amprobe (clip-on AC amp meter) on the system and watch the current draw. We have an EMS that shows current - the fan on our units takes 4-5 amps; when the compressor kicks on and the current jumps to 13-15 amps.

Sorry, I can't help on the remote control...Best of luck.

[JesPasnThru]

Thanks for your reply, Brad.

I seem to remember from the manual something like a 3 degree stretch for the diff b/w whether a/c functions on high or low. Otherwise, I’m not too sure. I did set remote on counter so my hand didn’t warm it. Also, you may be right about letting system operate on its own awhile longer w/o expecting precision. I’ll try again and see what happens.

I was working with it today while outside temp was 97, inside was 93. I set remote for 80 with fan speed set for auto and turned it on. Fan came on first then compressor shortly after. It ran for 15-20 min w/o really getting cold. I then pushed the “on” button on the ceiling controller (receiver?) and the fan speed increased and air got colder right away. It continued this way for 20 minutes until I turned it off.

Just makes me think the remote is not working properly. Maybe someone out there has updated the remote to a wall unit? Even analog thermostat would be better than this remote. Apparently they only made these for a few years because they were not trouble free.