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Discussion Starter · #1 ·
I just had a new 2-Stage Lennox furnace installed in my 2 story house. In the past, I have always had my thermostat set to "Auto", but am I understandingly it correctly that the Auto setting would not take full advantage of my variable speed motor to evenly distribute the air? Should I just be leaving it "On" at all times (in the winter months)? Or should I use the "Circulate" setting?
 

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Leaving the fan on all the time certainly does even out the temperature in the house, if you have flat spots. If you don't have any flat spots in the house then the fan on is just a waste of electricity.

The "circulate" setting tries to save a bit of electricity. Instead of allowing the fan to run all the time it starts the fan at random times for 10 or 20 minutes at a time to eliminate slight flat spots.

But again, if the climate is fairly even throughout the house then the fan on all the time is just a waste.
 

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Depends on if you feel warmer or cooler in different areas of your house. Sometimes a 2 story won't heat evenly with a 2 stage unit as you don't have the airflow in the ducting system to push up to the second floor on low speed. Do you notice anything significantly different from floor to floor and end of house to end of house? If you do then circulate or continuous fan is not a bad way of correcting those issues as there is a high probability you have an ECM motor on that unit which costs minimal to operate on continuous anyway.
 

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Discussion Starter · #4 ·
Depends on if you feel warmer or cooler in different areas of your house
Yes, there is a substantial difference in temperature between levels. If I set the thermostat to 68 degrees auto, the 1st floor will be 68 degrees, but then the 2nd floor is probably about 75 degrees. Likewise, my finished basement would be closer to 60 degrees. So I don't have a problem getting heat to the 2nd floor, I have a problem that there is TOO MUCH heat on the 2nd floor and not enough in the basement.
 

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"full advantage" is the wrong term.

ON will run it at 40% of full speed all the time.

Circ means it will run 20 mins ON and 40 mins OFF per hour. Depending on the thermostat you have you may be able to change that to a different timing. Read the tstat manual. I would run it all the time as it uses very little electricity and with a 2 story will help a lot. Single story not as much and some people don't like the sound or draft but that is rare, they may use CIRC.

ON will bring some of the heat downstairs but a ceiling fan is better.
 

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I agree with the above. Use circulate, and if that doesn't help enough, then set to on. It will increase the electricity usage, but most think it's worth it. (between $25-50/month depending on motor, for expensive electricity rates)

Cheers!
 

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Discussion Starter · #7 ·
ON will bring some of the heat downstairs but a ceiling fan is better.
I do have ceiling fans in every room, but don't use them in the winter. That may be part of the problem. Is there a guide for how I should set the fans (which direction, etc) to most evenly distribute temperatures?
 

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Some expensive fans have a reverse switch. In the Summer with AC you want to suck the air up on the main floor where you sit and not blow the heat down. In the Winter you want to blow the heat down. Not sure what you have. I imagine if you have a open stairwell and blow the heat down that will help. However it is rare we get people complaining of too much heat upstairs in the Winter. Usually with older homes with drafts and cold walls it is not a issue.

What you really need to do is have more open registers in the basement and slowly shut some of the upstairs registers so that more heat gets pushed downstairs. However you got to be careful to not overdo it and cause the furnace to overheat if you shut them too much. I would start and then run the furnace for 10 mins at least and watch the viewing window in the lower door. If it shows it is tripping on the high limit control then you overdid it. Also you can check the temp rise by sticking a cooking thermometer in the horizontal duct after it leaves the vertical plenum/bonnet and subtracting the house temp. Then you get the rating off the model# sticker and compare. Usually on low fire it is in the 20-35 F range and on high fire 35-65F range. I would recommend you check it.
 

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In the Summer with AC you want to suck the air up on the main floor where you sit and not blow the heat down. In the Winter you want to blow the heat down.
As much as I agree with you, it's insanely difficult to convince people that this is better. The "warm" air is still normally colder then body temp, in both cases, so people want the breeze during the summer and think they'll get sick from it in the winter. (despite it being nearly the exact same temperature.)

Now I just let people do whatever they want, and don't listen when they complain when a 10,000 sq.ft space, 15ft ceiling, won't keep them warm when it's -20*C outside.... Oye....

Cheers!
 

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I guess you have to try it both ways to see what you like.

I had a 2 story in Calgary with a open main to second floor and 8" foot windows on one wall. In Winter it was better to force the heat down and over the glass to prevent convection currents from going up and feeling drafty. In Summer it helped to reverse it but Calgary is not very hot and you can do w/o AC. Once the sun gets behind the top of the mountains at 5 pm the temp drops like a stone as you are in the shade.

Now you have the movie "Casablanca" with the big ole fans and I guess any air movement felt better.
 
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