Re:Ercot nearly at capacity for Texas power grid
by toast0 on Monday February 15, 2021 @06:12PM
(#26148910)
That's the gist. It's not much, but if the outside unit is iced over, there's not going to be a lot of heat exchange into the working fluid, so you're not going to get heat into your conditioned environment.
So, a defrost system will include a temperature sensor, and a resistance heater, and often something to signal the inside unit to run the emergency/auxiliary heat until (unless) the outside unit can get up to a temperature where it will work.
What does a defrost system includes? My dad manages a place where defrost system on one of the devices broke. Technician replaced something and hence it was fixed. IIRC it was temperature sensor. All defrost system does is periodically warms up the outside grill basically. It used to get stuck at -15C or so.