Lennox G61

[namber]

Two years ago I had a Lennox G61 furnace installed by a large HVAC contracter in the area. At the time my Maple/Chase thermostat's instruction manual said it is not for two stage furnaces. My furnace contracter told me that with the electronics in the G61 my thermostat is fine. I have now heard that it was improperly installed by hooking two wires on the W1 terminal and not using the W2 terminal. In essense I am not getting the savings from a two stage unit. Who is right?

[HVAC Pro]

2 stage was designed more for comfort than savings. The board will time the second stage if your thermostat is single stage.

Your furnace should always start on low fire and then shift to high fire after approximately 10 minutes of run time. If you want high fire to operate on a second stage call from the thermostat (temperature drop in the room) you will need a 2 stage thermostat. Simply call a contractor and have one installed if you want it to operate this way.

[t527ed]

unit is made to be wired either way. preffered way would be 2 stage thermostat. sometimes not enough wires to stat location to easily do. no real savings by 2 stage operation, 2 stage more for comfort longer run cycle on low fire means less temperature swing. timer can be adjusted for length of time unit runs on low fire before kicking up to high. different ways of wiring by different contractors, fact that unit was made for either set up there is no real right or wrong.

[namber]

Thanks folks.

[curry]

Originally posted by HVAC Pro
2 stage was designed more for comfort than savings. The board will time the second stage if your thermostat is single stage.

Your furnace should always start on low fire and then shift to high fire after approximately 10 minutes of run time. If you want high fire to operate on a second stage call from the thermostat (temperature drop in the room) you will need a 2 stage thermostat. Simply call a contractor and have one installed if you want it to operate this way.

What he said.

[mark beiser]

If you have a 2 stage thermostat installed, there is a jumper or dip switch on the furnace control board that needs to be moved so the control board will know there is a 2 stage thermostat. Otherwise 2nd stage will kick in after 10 minutes of 1st stage heat, regardless of if the thermostat calls for it or not.