Hi Rise Condo Thermostat Replacement - Need Help!!

[tangfj]

Okay, so I live in a high rise condo building and I want to replace my thermostat. I believe my building is a 4 pipe system. In any case, I need to replace my thermostat because I need a programable thermostat so that I can control my energy bill a bit better. In my building I only pay for the blower and there's really no need to have it on all the time.

So I took off the current thermostat and took it to the local Home Depot. The guy there said that it'd work with something that they had there so I got some programable Honeywell. When I got home and read the instructions, it said that if I had 6 or more wires to not use this unit. My current thermostat has 6 wires connected to a wire harness that then attaches to the blower. Does anyone have any clue as to what kind of thermostat I have to use? Also, how do I know which wire goes where? Do I have to go to a special contractor's store to get something to work?

I live in Chicago so if you know of somewhere to go please let me know! Thanks.

[LazyPup]

Would need some additional information...If you are in a high rise condo which receives HVAC from a central machinery room via a 4 pipe system it sounds like you have a Hot & cold deck circulating hydronic system.

What is the wire size of the wires on the present thermostat?

[Dean]

If you are paying for blower operation only, you are not going to see much savings. Probably not worth the trouble.

[LazyPup]

Dean is definitely correct in his assesment that there would be little to know actual savings.

An HVAC inside fan motor is typically a 1/4hp motor.

746watts = 1 HP, therefore the motor only uses 746/4= 186.5 watts.

Even if the fan was presently running 100% of the time and you reduced the run time to 50% duty cycle, the actual savings would only be 93.5 watts. It would be definitely more cost effective to simply make sure a couple light bulbs are turned off.