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mlhayes
Jun 19, 2008, 07:27 PM
Hi,
I have a Bryant Mid-Efficiency Gas forced air furnace. I live in the southwest, and have an evaporative cooler, no central air conditioning. So this furnace just heats.

I am tired of being hot with the evaporative cooler, and purchased a 11,500 BTW window A/C unit to cool my 1300 square foot home. It does a nice job of cooling the open part of the house but the bedrooms get a little warm.

Since the cold air return to the furnace is nearby I thought if I could somehow get my furnace blower to run (without heat, obviously) to circulate the air in my home the other rooms would be cooler.

The thermostat has an auto and fan position. When I switch to 'cool' and 'fan' I get nothing, the thermostat is turned down to 70 as well.

I am thinking since this house/furnace was not set up for a/c the contractor didn't set the thermostat to work this way.

Is there a way to allow my blower motor to run? Or should I call a hvac guy to come out. I don't want to burn up an expensive printed circuit panel!

Thanks.

T-Top
Jun 19, 2008, 07:48 PM
You need to turn the power off to the system and if you have a extra thermostat wire hook it to G on the unit and G on the thermostat. That should give you blower operation with the thermostat fan switch in the on position.

letmetellu
Jun 19, 2008, 08:01 PM
T-Top gave you a great answer. I have a second answer that would require you to change a wire twice a year this is in case you do not have any extra wires running to the thermostat.
On your thermostat move the white wire to the G terminal, when you are through with the heat in the winter, then in the fall move the white wire back to the W terminal.

To use the fan in the summer set the thermostat to Fan On. Good Luck

mlhayes
Jun 19, 2008, 08:11 PM
Thank you for your quick reply!

You were correct, those wires were snipped short and not connected on each end.

I did as you said, and the blower still does not come on. The breaker is on, the gas control valve is on, the fan switch is in the 'fan' position, and the other switch is in the 'cool' position. The thermostat is turned down to 70 degrees. Any further ideas?

mlhayes
Jun 19, 2008, 08:14 PM
letmetellu, you must have posted as I remarked on T-tops response. I'll go give your suggestion a try.

Thanks.

mlhayes
Jun 19, 2008, 08:30 PM
letmetellu, I gave your suggestion a try. I switched the white wire to the g terminal on the thermostat.

The blower came on, and I got excited. Then I smelled heat coming on too. I shut the gas control valve off. The small blower to the chimney was running, and the igniter kept cycling off and on. So I shut everything off.

Further suggestions?

Thanks for your efforts!

T-Top
Jun 20, 2008, 06:51 PM
I forgot to add. You need to make sure you have a jumper wire from RH to RC on the thermostat for it to work. My bad.

letmetellu
Jun 20, 2008, 07:32 PM
The wire must be removed from the thermostat W terminal and also on the furnace at the W terminal. If this is done you furnace should not get a heating comand from the thermostat.. I hope this works for you.

mlhayes
Jun 23, 2008, 09:57 AM
letmetellu,

I have been in Denver chaperoning a youth retreat for our church, but thanks again for your quick response.

I changed the white wire to the G terminal on both the furnace and the thermostat this morning, and I now have the blower only.

Thank you so much for your help, this should circulate the cool air (I hope) from the main part of my house where the one cold air return is to the bedrooms more efficiently.

T-top, thank you for your help as well.

Best regards,

Mike