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BillyHvac, Journeyman HVAC Tech
Category: HVAC
Satisfied Customers: 22636
Experience:  Endorsed for unlimited heating, cooling, oil burners, boilers, refrigeration, hydronics
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Bryant evolution thermostat blank screen .power to wiring but

This answer was rated:

Bryant evolution thermostat blank screen .power to wiring but unit still blank.

At what locations did you verify power to thermostat and what was reading?


Customer: replied 3 years ago.

used voltage detector. verified all units had power going to them.thermostat wires show live but thermostat does not power on

We may have voltage there but not to common to complete the circuit.

Are you using just a detector?
Does it pick up voltage as low as 24v ac?
Or is it a meter showing values?

Is the unit (air handler) in an attic?


Customer: replied 3 years ago.

has power A though D using low voltage light up tester. S1-S2 show nothing for room sensors

There are only 2 ways to have this control blank.

1 - the unit has no power or incorrect power.

2 - the unit has correct power but the control is defective. are certain the control has proper power...the air handler has power..then the control is defective.

This runs entirely on power supplied by the air handler.

There resoans for no power like tripped water safety switches in air hander drain, no power to air handler etc....but if you indeed have power to stat...then the stat is bad.


BillyHvac and 2 other HVAC Specialists are ready to help you
Customer: replied 3 years ago.

Was the thermostat ha replaced thanks

Thank you for the update.

Have a great weekend