The Problem My Nest thermostat was displaying the following error message when my Air Conditioner stopped working. The odd thing was that the breaker wasn’t tripped and if I reset it the AC would run again for a short time.   E24 WIRING REPORT No power to Rh wire detected. Learn more at nest.com/e24. The Symptoms of a Clogged Condensate Drain Line No power to the Rh wire.