1.  What will happen to my old thermostat? 

The old thermostat will be removed and disposed of, the wires will be disconnected and capped, and the junction box will be covered by a standard white outlet plate.

2. Why must QAS use a blank cover plate to cover the hole left after the old thermostat is removed?

 It is required by the National Electrical Code that the junction box remains accessible at all times. It can be covered with electrical plates, access panels, paintings, or furniture, as long as demolition is not required to reach the junction box. You may not patch and paint over the junction box without first having a licensed electrician remove it.

3. Will the cover QAS uses completely cover the hole? 

The hole may be slightly larger than the standard electrical plate. The footprint of the thermostat is also slightly larger than the standard electrical plate.

4. Can I have the hole covered with dry wall and painted?

 The only way to do this is to first have a licensed electrician remove the wires and junction box per the National Electrical Code so that the hole is safe to patch and paint.

5. Where can  I buy additional or replacement sensors?

They are widely available. See, for example Amazon or Home Depot.