Furnace blower seems to run a lot after installing programable thermostats?
I replaced the old dial mercury thermostats in my house with programble ones, i have the new thermostats set at 65' but my furnace blower seems to run about every 20-30mins for about 5-10mins, and my house temp is around 70-75 is this normal or should
That is probably normal. With a digital thermostat, the setpoint is more accurate therefore you have more cycles for shorter periods of time. The old mechanical type allowed huge temperature swings so the unit would come on less often but run longer.