Some questions about my NEW 95% effecient gas furnace

digitalplumber · 11-20-2012, 09:43 AM

We dont know what his old was, so its quite possible that if the new one is larger, the return air is too small?

As yuri states, could be on wrong blower speed for heat? Could be wired for high heat all the time instead of low then high if necessary.

Mr Blotto · 11-20-2012, 01:08 PM

So back to the blower speeds, my furnace is a single stage with a multi-speed blower. Is there an easy way (when my furnace is not on) to make the blower run at a very low speed? As a bandaid while I was waiting for my new furnace to be installed, I had to run the fan continuously and was amazed on how balanced it kept the house (temp-wise).

Do I have to get a special t-stat to do this? Will the furnace need to be re-wired? Is this just not recommended?

Thanks!

digitalplumber · 11-20-2012, 04:26 PM

Dont know your thermostat but you should just be able to switch it over to "fan" from "auto".

**beenthere** · 11-20-2012, 05:02 PM

Slowing the blower is not hard to do. Should check temp rise across the heat exchanger before slowing it, and after slowing it. if you had a contractor install it, you cn probably have them come out and slow it for you.

raylo32 · 11-20-2012, 07:04 PM

Exactly, as I said above slowing the blower is a 2 minute job by moving a jumper on the circuit board. Like BT says make sure the tech checks the temp rise before and after to avoid approaching the high limit.

carmon · 11-20-2012, 08:17 PM

never mind the hi limit... you must stay inside the maximum temperature rise of the furnace.....

Mr Blotto · 11-21-2012, 07:03 AM

I guess what i am asking is is there a way to have the blower motor run at its current speed (hi) when the furnace is on (when the thermostat calls for heat), but when the heating cycle is done, instead of the blower turning off, could i have it run at a very slow speed - just to slowly circulate the air in the house?

Mr Blotto · 11-21-2012, 07:21 AM

I guess what i am asking is is there a way to have the blower motor run at its current speed (hi) when the furnace is on (when the thermostat calls for heat), but when the heating cycle is done, instead of the blower turning off, could i have it run at a very slow speed - just to slowly circulate the air in the house?

digitalplumber · 11-21-2012, 07:41 AM

Quote:

Originally Posted by Mr Blotto

I guess what i am asking is is there a way to have the blower motor run at its current speed (hi) when the furnace is on (when the thermostat calls for heat), but when the heating cycle is done, instead of the blower turning off, could i have it run at a very slow speed - just to slowly circulate the air in the house?

did you see my answer above?

Mr Blotto · 11-21-2012, 10:04 AM

Quote:

Originally Posted by digitalplumber

did you see my answer above?

Hi - Yes - i did, however whether the termpstat is on Auto or Fan, my blower operates at high speed. What I am wondering is if I can set it on Fan, and have it run at the slowest setting while the furnace is not on, and then when there is a call for heat, have the blower go to high.

raylo32 · 11-21-2012, 10:17 AM

I don't think you can do that.

It might be possible with a 2-stage furnace... but I am not sure whether the fan would blow at first stage low speed or 2nd stage high speed in Heat Mode when there is no call for heat. I'll try mine later (I have a 2-stage furnace) to see what it does. I know this won't help the OP but it'll answer a question of mine.

Mr Blotto · 11-21-2012, 10:20 AM

OK - I didn't think so, but it was worth a try.

Thanks

**beenthere** · 11-21-2012, 04:46 PM

Some furnaces have a fan speed terminal. This is the terminal that is energize when the stat is set to fn "on" and there is no call for heat or cooling. Yours may or may not have it. Sounds like it doesn't, but you can look and see.