Presence of a reversing valve 5. Compressor is indoors and ita#39;s an air-to-air system 6. Presence of an outdoor thermostat connected to control wiring 7. If it is winter and the unit is operating, ita#39;s a heat pump. 8. You find a two-stage thermostat.
|Title||:||Principles of Home Inspection|
|Publisher||:||Dearborn Trade Publishing - 2003-01-01|