A/C Not Working...ON HOTTEST DAY OF THE YEAR!

Brownie · 06-13-2017, 07:30 AM

I replaced the standard analogue Coleman Mach thermostat with a Coleman Mach digital last March and both the heater and A/C worked great . . . until last week. Heater still works fine, but when I switch to A/C I hear a click, and the LCD display shows "00", then goes blank, then click and back to "00". It will continue doing that until I switch it off. The fan still works on the "manual" setting. I've reset the breakers and checked the fuses, but can't seem to fine one that's blown.

Is there a hidden reset switch for the A/C like the one on the furnace? I removed the inside A/C cover, but there's nothing in there. Is there a switch under the cowl on the roof? Could I be out of coolant? Do I need to call a mobile technician? (I'm full-timing as Campground Host, so leaving at the nearby Camping World for 2-4 weeks until they can get to it is out of the question.)

Any suggestions/advise would be greatly appreciated. Thanx!

RedHorse1 · 06-13-2017, 07:44 AM

To me it sounds like something is up with the thermostat. I'd start by checking the connections to the thermostat, if that's good try putting the old one back in. If you don't have the old one look for an RV store or Lowes nearby where you could get a temp replacement. It might be possible to trick the A/C into running by bypassing the thermo which would verify it does/doesn't work. I haven't attempted that and would have to study a wiring diagram before attempting it tho.
"Summer is coming, John Snow."

Sundancer330 · 06-13-2017, 07:56 AM

Found this on IRV2, it may give you some tips. http://www.irv2.com/forums/f54/colem...ues-91009.html

Camper_bob · 06-13-2017, 08:04 AM

I would double check the wiring connections on the new stat first. Those tiny wires can be a little tricky, you could just have a loose connection.

+1 to putting the old one back in. You kept it right? I keep everything until the new install has proven itself without question. In fact, I think I still have my old stat, and I don't even remember how long it's been since I installed my digital.

This will at least get you through the hottest part of the season, then you can trouble-shoot the digital stat later.

A brief scan of an owners manual I found online didn't net a result for that error code, but it has wiring diagrams:
https://olivertraveltrailers.com/wp-...l_19763761.pdf

ETA: I also found some chatter on various forums about interference in the 12V system caused by fluorescent lighting (or other) that could be a potential cause? Do you have anything on your 12V system that could introduce interference? I'm thinking cheap LEDs perhaps?

SloPoke · 06-13-2017, 08:22 AM

Quote:

Originally Posted by Brownie

Do I need to call a mobile technician? (I'm full-timing as Campground Host, so leaving at the nearby Camping World for 2-4 weeks until they can get to it is out of the question.)

Any suggestions/advise would be greatly appreciated. Thanx!

Yes... a Mobile tech is your best choice. They can assess it, and either fix it or order a replacement for you at the same visit.

... and how did you find a CW that can get it done in 2-4 weeks? That is unheard of around here. They are always a minimum of 6-8 weeks waiting for parts while our unit is torn apart sitting there. You are Lucky!

stateboy · 06-13-2017, 08:26 AM

I would agree with Red Horse1 when he said to 'trick' the A/C. The thermostat is simply an on/off switch. The temperature portion of the thermostat that tells you how hot/cold the room is replaces you from having to remember to turn your unit on or off (besides feeling too hot or cold).

If you remove the thermostat and touch the wires together that your thermostat would normally 'join' together when a demand for A/C (or heat, depending on the season - same principle), it should come on. There may be a slight delay for timed relays to engage but it should come on. If it doesn't, you need to replace the thermostat or perhaps the batteries in the thermostat (I had to do that yesterday in my house to get the thermostat to respond). If you keep the wires together, the A/C will stay on until you remove the wires from touching each other. That makes YOU the thermostat and that's why we have thermostats so we don't have to stand there holding wires together or leave the premises and forget to disengage wires.

I hope this helps. Essentially, doing this will tell you if it's a thermostat issue or something else in the unit and/or wiring system.

Sent from my SM-N910V using Tapatalk

Doug · 06-13-2017, 08:26 AM

Looks like you could jump red to yellow and green if needed.

Doug

troutslayer · 06-13-2017, 03:34 PM

I also switched to the digital one but still have the old one. I can send it to you if you still need it to make your test.

**norty1** · 06-13-2017, 03:40 PM

I have a buddy who zapped his new digital thermostat by wiring it up wrong. A new one solved the problem. I would try re-installing the old one and triple check the wiring colors.

Marcm157 · 06-13-2017, 05:39 PM

Nothing more to add here tech wise but I will also offer up my analog T stat as Troutslayer did if needed.

Brownie · 06-14-2017, 04:36 AM

...to everyone who responded. Your quick responses and assessments of my options are why I love the JOF!

I've double/triple checked all the connections - removed wire nuts, restriped the wires, and reinstalled the wire nuts. Still get heat and fan (both speeds), but no A/C. I did keep the original analogue t-stat - just in case . . . (Mrs. Brownie didn't raise no dumb boys!) I reinstalled it, but it's not working at all. It has a tiny tubular glass fuse (2V/250W) that's blown in it. Tried a local hardware store, but the kid working there sold me a 2 milliamp fuse. Needles to say, that popped the second I turned the switch onto heat. So I re-reinstalled the digital t-stat (at least I can run the fan). Plan to go into town today and find a 2V/250W replacement fuse either at Home Depot or Camping World. If I can find one, I'll re-re-reinstall the analogue t-stat and just use it until I can get a replacement digital.

Since it worked for 3 months, and now it doesn't, after reading your posts and playing with both t-stats, I've determined that the digital one has a faulty function control switch. Guess I'll be contacting Amazon for a return/replacement unit.

Thanks, again, for all your help!

jcoyle · 06-14-2017, 05:19 AM

Just thinking and you probably have already thought of it, but the new digital one doesn't have the fuse in it does it? Perhaps you could borrow it and save a trip into town?

SouthCo · 06-14-2017, 05:24 AM

The digital Coleman one does have a fuse but no sure if it's the same.

**norty1** · 06-14-2017, 06:54 AM

I still have both of my old analog ones hope they are never needed.

Sent from my iPhone using Tapatalk

Camper_bob · 06-14-2017, 08:34 AM

Are you "Up North" for the summer yet? Are you staying in TX this year? If so, where are you staying? I'm making a short trip out to Junction from San Antonio area this weekend; if you're staying reasonably close to my route, I can stop by if you need a hand? Not sure how much help I could offer, but I thought I'd offer it anyway! LOL!

You may also like: