Frozen Heat Pump

michaels

Not intended to scare, just so that if we do get people with questions, the relevant thread is easily found.

akwexavante

Just my little bit.

ASHPs work best switched on 24/7/365 inc DWH at a set temperature that's comfortable for you. Possibly maybe a slight setback, a couple of degrees overnight if the house (Bedrooms) are too warm.

Having a secondary heat source compounds the problem even further. A stove heats up the home, the ASHP turns off.  As the house cools down overnight and the ASHP kicks back in (from a Cold Start) when the outside temp is cold, it will struggle to defrost because it can't heat up enough water to then successfully defrost.

ASHP's become inefficient, expensive to run, and can become problematic when you fiddle and turn things on and off. Turn everything on, find your happy temperature, walk away and leave it alone. 

It'll be less troublesome and cheaper to run.  If it isn't then explore whether your home is adequately insulated and or if you should have had an ASHP installed in the first place.

I have a stove and when it's used i know that my ASHP will struggle and even fail to restart from a cold start in the early hours.