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My AC isn't coming on. I have a Honeywell RTH6450D

Customer Question
My AC isn't coming...

My AC isn't coming on. I have a Honeywell RTH6450D thermostat, fairly new. I have tried removing and checking batteries, turning off breaker at electrical box and turning power switch to hvac off both for more than 30 seconds. Whenever I turn desired temp lower than room temp "cool on" light blinks for a while and nothing happens.

Contractor's Assistant: Just to clarify, do you think this is a larger HVAC problem, or something specific to the thermostat?

I don't know. I have a new furnace as of 2 months ago and the AC is about 11 or 12 years old and was working fine until about 2 days ago

Contractor's Assistant: Do you plan on doing the work yourself?

No, I have a call in to my hvac guy but it may take a few days and we're having a heat wave here in Denver.

Contractor's Assistant: Anything else we should know to help you best?

No, just wondering if there might be anything simple I can do

Submitted: 1 year ago.Category: HVAC
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Answered in 9 minutes by:
7/9/2017
HVAC Technician: Phil, Mechanical Engineer replied 1 year ago
Phil
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 9,807
Experience: Retired HVAC/ Electrical & Boiler contractor. Industrial
Verified

Hello, if you have changed the air filter in the last few days, the blower access door may not have been refit properly... there is a door switch there that keeps the system off if it doesn't close properly. check that first.

We can go from there.

.

I am a retired mechanical engineer and HVAC/ electrical/ refrigeration and boiler contractor ... with 56 years in this business.

I will go in depth with you, and up to a 6 hour time limit.

.

All I ask is please select the ***RATING LINK*** at the top of your page before leaving, that is the only way I am credited through the site.

Rating does not affect your charges nor ability to refund if not satisfied.

.

If you can agree to that, lets continue by all means.

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