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Honeywell thermostat the readout (LCD) is blank and A/C is not blowing.

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Re: honeywell thermostat

You have lost power to the A/C system. Check that the Emergency switch has not been turned to the off position by mistake. If it is in the on position you will need to inspect the indoor unit to see if an access panel may have opened slightly causing the door safety switch to open and turn power off to the unit. This is typical found where you replace the air filter. If neither of these help, check the circuit breaker box for a tripped breaker. Cycle the breaker for the A/C system and inspect the thermostat to see if it is displaying any information. If still blank, you may have a bad transformer or something else wrong and a technician will have to diagnose. Hope this is helpful.

Posted on Sep 12, 2007

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