On 04/28/2017 11:33 PM, dpb wrote:
On 04/28/2017 10:15 PM, DoN. Nichols wrote:
....

How will the board continue to work without backup power?

...

That's the point; it doesn't need to.

To amplify, these boards retain their settings on power-off so if use
the NO contact and the "COOL" side so closes on TSetpoint, when power
comes back on the relay won't close to restore power to AC if the
temperature is below the turn-on setpoint.

Which use begs the question of why OP would leave the AC energized once
it's even remotely close to freezing, anyway...a solution looking for a
problem here.

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