On Sun, 21 Dec 2008 08:33:31 -0800 (PST),
wrote:

All,

Last night, the temp here in Iowa dipped down to around -10 with a -35
degree windchill. This morning I noticed the temp was about 4 degrees
off of where I had the thermostat set (It was set for 68, but the
heater was running continuously to keep it at 64). Right now, the
temp has risen to about -5 and the heater is running continuously to
keep the house at about 66-67 degrees.

When you look at the windchill, I think this is probably one of the
coldest days since I moved in 2 years ago.. Does this sound normal, or
could there be an air flow problem? The amount of hot air coming out
the vents seems to be normal compared to warmer days.



What kind of system. One time this might be normal is if the system
is a heatpump with electric heat strips as backup. Our old unit would
let the heatpump take care of things until the indoor temp dropped
about four degrees below the setpoint on the thermostat, then it would
kick in the heat strips. If you are running a heatpump in this sort
of cold, switch it to emergency heat (the heatpump is wearing itself
out for nothing) and turn up the temperature until it reaches
something comfortable, ignoring what the thermostat setpoint shows.