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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 6022
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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Have one AC unit to cover two levels. Downstairs will cool,

Customer Question

Have one AC unit to cover two levels. Downstairs will cool, but upstairs will not (it will, but sporadic when it does... when i turn thermostat off, it will briefly turn on and flush any air out for about 20 seconds then turn off). Thermostats were replaced, since I had thought they were the root of the issue. Issue has been sporadic for over the past year, but now when we really need the A/C, it's acting up. Usually by turning thermostat on and off a few times over the last few days, it would trigger AC to turn on upstairs as well. Downstairs seems to be working fine.
Submitted: 1 year ago.
Category: HVAC
Expert:  BillyHvac replied 1 year ago.


What is make and model of your zone panel?

Customer: replied 1 year ago.
Customer: replied 1 year ago.
I noticed this has 3 zones... zone 3 is "optional"... zone 1 and 3 are the ones hooked up to thermostats... I have never touched this, and these settings have been in place since purchasing the home.
Expert:  BillyHvac replied 1 year ago.

Usually this is a sign that zone 2 in board failed and was moved to 3.

If you set downstairs off and upstairs on what does diagnostic do?

Customer: replied 1 year ago.
upstairs will not turn on when I put thermostat on... a couple nights ago, i turned downstairs off, then upstairs on... wouldn't work... reset breaker box for about 30 seconds, when it turned back on started working again.
Expert:  D.E. Anderson replied 1 year ago.

Hi, do you still need assistance with this?