you're not supposed to keep system on all the time

It is OK to keep the system running for 20+ minutes.  But if you leave the stat in heat on position all the time, the system will remain on all the time.  Your house will become an oven.  Normally the system turns on intermittently -- it only needs to run when the temperature drops below the programmed value. 

It sounds like there is something funny with the thermalstat.  You chould probably buy a simple one at Homedepot for $20 and install it by yourself.  The control wires are color coded.  I remember there were only 6 or 7 wires.  Please read the installation manual included in the new stat first.  Then open up the old stat, take a note of the existing wiring.  When I installed my super-duper progammable stat, I actually put labels on all the existing wires first before I unsrewed them.  It was a very small DIY job. 

 

所有跟帖： 

• It seems the thermstat works fine. -Morning3evening4- ♂ (719 bytes) () 01/07/2011 postreply 21:36:17

• By the way, even the furnace does not starts, -Morning3evening4- ♂ (413 bytes) () 01/07/2011 postreply 21:46:03

• is igniter ok -rx300- ♂ (1049 bytes) () 01/08/2011 postreply 07:50:43

• pull off the thermostat, twist these 3 wires -borisg- ♀ (112 bytes) () 01/08/2011 postreply 10:41:05