Gas and Oil Home Heating Furnaces - Easily convert single speed furnace to dual speed?
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jkozlow3
04-16-06, 08:44 AM
Hello. In my brand new townhome, I have a Lennox G40 single speed 80% efficient furnace. I like to leave the fan on continuously to circulate air throughout the house. Is there an easy way to convert the fan to a dual speed unit so that it moves at a higher speed when the heat kicks on but a slower speed when the heat goes off?
If so, how? What do I need?
Thanks!!
If so, how? What do I need?
Thanks!!
Grady
04-16-06, 04:27 PM
I'm sure the fan in your furnace is already a multi-speed but likely factory set on low for heat. If this is the case, there is no easy way to change it.
mbk3
04-16-06, 07:26 PM
I guess you could set for low speed on the "fan on" setting & maybe med or hi on heating speed..If you don't have ac. Probably won't get the best heat quality..I think i would have a service tech take a look
jkozlow3
04-16-06, 10:29 PM
The model I have (Lennox G40) is advertised as a single speed unit. The next model up is advertised as dual speed. Now whether that means that it has the capabilities of dual speed but is disabled by the factory, I have no idea.
So, what are the ideal speeds for heating & AC anyway? My new townhome doesn't have AC and I'm not sure if I'll need it as it doesn't seem to get that hot here in Colorado (no humidity either), but I'm just curious in case I add it later. Ideally, what speeds should be used for heating & AC? And what happens if I want to add AC later to my single speed furnace? Will the installer be able to adjust the fan speed if necessary?
Thanks.
So, what are the ideal speeds for heating & AC anyway? My new townhome doesn't have AC and I'm not sure if I'll need it as it doesn't seem to get that hot here in Colorado (no humidity either), but I'm just curious in case I add it later. Ideally, what speeds should be used for heating & AC? And what happens if I want to add AC later to my single speed furnace? Will the installer be able to adjust the fan speed if necessary?
Thanks.
Grady
04-17-06, 05:28 PM
Your furnace is a single STAGE unit. Fan speed needs to be adjusted by measuring temperature rise. You should contact the installer to make the adjustments.