Hi hope you can help. We have a carrier unit that is approx 6 years old. The thermostat has no reading (also a carrier). Checked fuses on unit itself they are not blown. Flipped circuit breaker - still nothing. Took working thermostat from dowstairs up and still no reading/action of any sort. Any guidance will be appreciated!

Transformer could be shot...

I say check your transformer as well.

I, 3rd that motion

I, 3rd that motion

Thanks to all! Will proceed to transformer. Is this repair a diy? (As a non hvac but pretty handy). Or give up, call the pros and dig the debt-hole a bit deeper?

If you have a voltmeter it is probably something you can check yourself. See if you have 24VAC output from it.

Thank you all! And thank God for a handy husband and a friend at Airco. Turns out a loose wire that had burnt and was not making connection. Portable thermostat said 125.4 degrees in the attic you guys be careful working in this heat. Thanks again what a cool website.

I`m so very happy to hear from someone that gives the credit of something good to whom it belongs. Thanking God ,He is the one that makes everything possible