help with service call

[tyranadome]

have ac with gas furnace system that will run have ac with gas furnace system that will run for thirty seconds then everything will cut off for thirty seconds then everything will cut off including thermostat in ac. It will come on & including thermostat in ac. It will come on & run for a couple seconds & cycle off & on. runs run for a couple seconds & cycle off & on. runs fine in heat. changed transformer but same fine in heat. changed transformer but same thing. will pressure switch make thermostat go thing. will pressure switch make thermostat go blank? blank?

[ncboston]

See posts on the other thread you started.

[OldSchoolMech]

So.......Where did you get your training at???

The preasure switch will not make your T-stat go Blank. I would be looking at my low voltage wires and feeds first.

[tyranadome]

I was trained in a hot attic.

I didn't think pressure switch would. It does same thing every time. 30 sec on the cycle on & off for 5 sec. I will check wires again. Thanks!

[OldSchoolMech]

While you where in that hot attic did anyone show you how to jumper out the preasure switch or to use a multi meter to see what the system power is doing?

Are you trying to get the heating circuit up and going?
Or you just need the blower on for AC?
See the problem with a little info.

[Joehvac25]

So.......Where did you get your training at???

The preasure switch will not make your T-stat go Blank. I would be looking at my low voltage wires and feeds first.

Damn I posted something of the same nature in other one, didnt know there was 2 threads.

[tyranadome]

Trying to get ac up. Somebody else was calling me for advice. They swear its wired right but he just burned his transformer. So thanks for help.

[socotech]

Check compressor contactor. Verify coil voltage is rated for 24v. You have got something dragging voltage down. I have seen this a few times.

[drife678]

whenever replacing transformer make sure to install low voltage fuse inline with 24 v (R). had a call the other day where the unit had been down for two months average joes kept installing new xfmr and couldnt find problem. called pro, unit fixed in 45 minutes new xfmr, 5 amp fuse and replaced shorted contactor coil. lol average joes are so fun to follow.