1.
In certain weather Heat Pumps may have ice build up--this is not uncommon.
If the ice does not thaw normally, switch the thermostat to emergency
heat/auxillary heat and call for service.
2. Extreme teperature
setting changes can be difficult for the system to facilitate.
In very cold weather, for economy and comfort, we advise no more
than 4-5 degree temperature changes during these times.