help! a/c comp. want start?

[sovereign]

a/c was working fine last week, now when i turn it on , only the fan blows and the compressor want start?

[overlander63]

Originally Posted by sovereign

a/c was working fine last week, now when i turn it on , only the fan blows and the compressor want start?

Check this thread, good luck with it.
Terry
http://www.airforums.com/forum...ad.php?t=12213

[uncleneal]

That seems to be going around, Firday I had cold air, Saturday only fan. A/c is a Coleman Delta TX. I've only had the unit about 10 months, so have no history on it. Anybody know where I should start checking?
Neal

[sovereign]

here are some pix i took of the a/c control box. can somebody tell me which relay is the start relay? etc.? and the transformer in the pix is it surpose to put out 24 volts? i checked the wires in the thermostat r,y and g and there is no voltage goinig to any of the wires help, please

[overlander63]

Originally Posted by sovereign

here are some pix i took of the a/c control box. can somebody tell me which relay is the start relay? etc.? and the transformer in the pix is it surpose to put out 24 volts? i checked the wires in the thermostat r,y and g and there is no voltage goinig to any of the wires help, please

Okay, first, check to see if you have 110v going in to the transformer. If you do, check to see what voltage you have coming out of the transformer. My unit is supposed to put out 12v DC. If you are geting nothing coming out, and 110 going in, the transformer is the culprit. If you are not getting 110 to it, check the breaker and make sure it is not tripped, or broken. You should get 110 AC between the outlet of the breaker, and the common wire.
Terry

[Pahaska]

Make sure that the thermostat hasn't failed. Typically, on these units, the fan runs continuously and the thermostat cycles the compressor.

I had a thermostat on my previous trailer that wouldn't turn off except at precisely one point on the dial. If I iggled the knob, it would turn off. It could be as easily one that won't turn on.

[TomW]

Originally Posted by sovereign

here are some pix i took of the a/c control box. can somebody tell me which relay is the start relay? etc.? and the transformer in the pix is it surpose to put out 24 volts? i checked the wires in the thermostat r,y and g and there is no voltage goinig to any of the wires help, please

You had to remove an access door to take the picture. Was there not a schematic on the inside of the door?. I hate to walk on Argosy20, but in my limited experience, thermostats are usually managed with 24 volts AC.

I think your start relay is the on the lower left of your picture judging by the wire colors. Can you take a bigger picture showing the wires exiting at the bottom? One set of wires will go to the compressor; The other set will go to the fan motor. My most recent experience with Airstream A/C had brown wires going to the fan motor capacitor.

Bear in mind I am an avid enthusiast, not a professional. But I will help if I can.

Tom

[overlander63]

Originally Posted by tcwilliams

You had to remove an access door to take the picture. Was there not a schematic on the inside of the door?. I hate to walk on Argosy20, but in my limited experience, thermostats are usually managed with 24 volts AC.
Bear in mind I am an avid enthusiast, not a professional. But I will help if I can.

Tom

Not a problem, Tom. Mine, for whatever reason, ran on 12v DC.
I just checked my home A/C, just because, and my meter says it is working with 27.5 volts. AC.
Terry

[sovereign]

i will take another pix tomorrow, when you check the voltage from the little transformer. do you have to disconnect it on one end? i took a volt meter and checked the wires inside the trailer at the thermostat {removed the cover of the stat} and got no voltage, with the unit on. also all of the fans , the one inside and out run

[davidz71]

Sovereign,
The transformer is in the upper right hand corner of your first picture. Set your meter for AC voltage of at least 125 v. I had to go out to the trailer and look up the drawing I made before taking the transformer out. You will see yellow and red wires coming out on the right hand side of the transformer. On the left hand side you should see a white & yellow wire as well as a black wire. Check current across the white/yellow and black wires first. I think this is the 125 v. side. If it shows current going into those wires then you know that you have power there. Also look for a white tag on the transformer which might tell you which is the high voltage AC side. If it showed appx. 125 volts then go to the other side with the yellow and red wires. Set the meter for up to 24 volts DC and measure the current across them. If it shows less than 24 volts then it is suspect. I believe mine only showed 9 volts coming out of the transformer and none at the thermostat. If this is what you find, make a drawing of where everything connects, take out the transformer and hit a few electrical supply houses. I found 2 transformers, one of which was entirely too big to fit in the space and one that was just a little larger than the one I took out. I had to fabricate another mounting bracket but it was no trouble at all. Be extremely careful with your meter to be sure you don't ruin it or yourself.

[sovereign]

yaaaaahhhooooo!!!! i fixed it!!! but not without everybodys help. thanks everybody. it turns out that the little transformer was bad, 11o v input and 0v output.

[john hd]

hey ya gotta like that!

sure is less expensive than the answer most rv places would have given you!

john

[Inland RV Center, In]

All of the Armstrong airconditioners used a 24 VAC transformer for the wall thermostat.

Unfortunately, with some inexpensive volt-ohm-millammeters, you can set the scale to DC, and still measure AC. The reading will not be correct, but you will get a reading.

The two relays are fairly common, and can be purchased at most any Airconditioner or Refrigeration parts source. The physical size of the relay doesn't matter, but what does matter is the ratings, in volts and amperes.

Andy

[sovereign]

in my case , i set the meter both ways ,and still got 0 volts?but on the dc scale the meter was pegged on 15v and 150 when checking the 110 side, but was correct on the ac scale