This is my second two-story house. The previous one was able to keep the temperatures on the 1st and 2nd floors about one or two degrees apart in winter. This house has a difference of about eight degrees.

The only difference I can see is the previous house had only a stairway allowing air flow between floors. In the current house, both the living room and the front entry are full-open from 1st floor to 2nd floor ceiling. No barrier to hold the heat down.

I've played various games with 1st floor and 2nd floor settings for the vents and thermostats with no success. Essentially the two 1st floor units run, and the 2nd floor unit never kicks-in. If I get the 1st floor to 72 degrees, the 2nd floor is 80. Has anyone found a trick to get a more efficient use of heaters in a two-story house?

I remember in the old days there was a door leading to the stairway to the 2nd floor and that's how my grandparents kept the downstairs warm, by keeping that door closed. In current houses you're pretty much heating a barn.

Some friends of mine use ceiling fans to push the air down in their 2 story. Said if they don't, it gets too hot in the upstairs. Might be worth a try.

Yeah it's a bitch..........heat rises and cold falls.

Two story houses are neat on paper.


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We have one big downstairs unit for both floors. A second for upstairs isn't doable. So twice a year you open or close the vent from it going upstairs. In Winter it cuts off warm air going up because the warm rises anyway up the staircase. In Summer it's opened to allow cool air upstairs. We'd like a better system, but the next owner gets to pay for that.

Oh, a friend built this big place in the country with upstairs open to downstairs kinda like what you said. Last I saw of him, he was nailing up these foam sheets to seal the upstairs off and duct taping the seams to keep it warmer. I guess it works sorta, but I doubt you'll be seeing it in "Southern Living".

He asked me how it looked. I said the blue tape on white foam was a nice contrast.

I didn't ask if the contractor was The Three Stooges.

Something tells me that's not going to help you much...

Mount the thermostats midway up or two thirds the way up

Is this a forced hot air unit that also does A/C? If so look to see if there is one large damper by the unit that splits the second floor from the first. In the summer you need to adjust so more air goes upstairs, in the winter adjust so more is headed to the first floor.

Pagosawingnut

You hit the one thing I wasn't doing. I have a ceiling fan in the living room. (When I'm standing on the 2nd level, the fan is about thigh-high.) I'm going to leave it running for while and check the temps. The blades are pushing air down, which will be working for me. Surely that will help bring the temperatures closer t each other. If it is a two to three degree difference, I'll be happy. Eight degrees doesn't cut it.

Thanks for jogging my brain.

So you can imagine my interest in the issue, currently its single digits here and blowing about 20mph.

I use a ceiling fan in my place and its always on. I have 10' eaves and the ridge is up about 14'. Usually the fan is on the slowest setting but occasionally I hike it up to mid speed. I don't see how in a closed house it'd make a difference if the blades draw air up or push it down. Either way, the air is circulated and I'd think air brought up and thru the fan would travel back down along the ceiling line and head back to the floor along the walls, only to be drawn back up. I do have mine switched to blow the air down.

I have radiant heat in my concrete floor so the theory is you warm everything up. The floor is 70, the walls, sofa, kitchen table,.....all 70.

Try leaving the fan on medium for a few days and tell us what happens.

I put the fan on high but the air movement made it "feel" colder downstairs. I backed it off one notch and it was magic. Before adding the fan, the temps were 81/73. After two hours it was 76/73. In the past hour the upstairs temp has moved between 76 and 77. Downstairs is set on 73. The kicker is that I with the warm air being pushed down, the lower units have run less, so I'm thinking the cost of running the fan is more than offset by a savings on the lower heater units.

Tomorrow when I get up I'm going to turn on the fan, and let it run all day, and turn it off when we go to bed. The heaters are set on 60 degrees at night and never come.

My guess is that if I ran the fan on high, I could probably get another degree closer, but I think I'll stay with what I've got if I get the same results tomorrow.

The big temp difference was always most noticeable in the early morning when the lower heaters kicked in. You could get about half way up the staircase and it felt like you were walking into a blast furnace. I'm curious to see the difference tomorrow morning after I've had the fan running.

I didn't get the results I hoped for this morning.

@2:30am - 46 outside, 70 bedroom downstairs, 69 kitchen downstairs, 70 upstairs

@6:00am - 43 outside, 69 bedroom, 70 kitchen, 79 upstairs

At 6:00am I turned the living room fan on its middle setting.

@7:00am - 43 outside, 72 bedroom, 72 kitchen, 81 upstairs

@8:00am - 41 outside, 73 bedroom, 73 kitchen, 82 upstairs

@9:00am - 43 outside, 73 bedroom, 73 kitchen, 81 upstairs

@10:00am - 43 outside, 73 bedroom, 73 kitchen, 77 upstairs

By middle of the afternoon the upstairs was only two degrees warmer than the downstairs while the fan ran.

Tomorrow morning I'm going to crank that fan to full afterburner as soon as I get up and see what transpires. Maybe it needs to be on high to counteract the two heater units downstairs when they first come on in the morning.

The first thing that should have been done was the HVAC contractor should have run a manual J sheet. You obviously have your areas zoned but not correctly. That is all water under the bridge now. You might consider placing your thermostat in your return air chase.

I'll do a search of the house documents. Luckily the original owner saved a Hell of a file of documents on the construction and appliances. I'll see if I can find anything related to the HVAC Manual J Worksheet.

This morning I got the following readings running the fan in the living room on high -

@8:00 - 27 degrees outside, 73 bedroom, 73 kitchen, 79 upstairs

@9:00 - 34 outside, 73 bedroom, 73 kitchen, 77 upstairs

@10:00 - 38 outside, 73 bedroom, 73 kitchen, 76 upstairs

Looks like the speed of the fan had a positive affect on the temperature upstairs, but short of lying the house on its side, I doubt I can get the temperatures more equal between the two floors.

Anyone staying in the upper bedrooms is just going to get smoked-out by about 7:00am, unless I reduce the settings downstairs.

Thanks for the thoughts and ideas.

I'm under the impression you're not running the fan continuously and that'd be a mistake.

Get used to it. Leave the fan on an approved setting and walk away.

quote:

Originally posted by Scott King:
I'm under the impression you're not running the fan continuously and that'd be a mistake.

Get used to it. Leave the fan on an approved setting and walk away.

Scott is correct. Even when heat is turned down at night the heat is still rising.

You might even want to reverse the fan in the cooling months. It will help the A/C work better also.

When it's cold outside, in the heated rooms the effect of "thermal pads" when the temperature difference between the floor and the ceiling reaches a few degrees. There are many ways to combat this phenomenon, but no final decision.
Heating should be as close to the floor.
Underfloor heating, floor heating radiators ceiling. Forced convection.
Naturally, preventing free air between floors.

I've had a couple of two-story homes in my life...in fact the one before we moved here three years ago was one of them.

Here is how I dealt with the potential heat differential in both of mine...

We had a forced air furnace, with heat going only to the upstairs level and the only thermostat on that upper level too. The cold air returns ran through floor vents into the lower level where the furnace was located.

On the lower floor, I had a nice large "pellet" stove which had an electronic lighter. Both floors and all walls were very well insulated.

The result was a good balance, as the amount of heat upstairs was regulated by the thermostat there. As the air cooled, and was pushed down by the natural circulation of warm air arriving into the upstairs directly from the furnace, the "cold" air going into the bottom level was not really cold...usually about 65-70° F if the upstairs thermostat was set at 72° or so.

So, if it was too cool on the lower level when I walked downstairs in the morning, I would hit the electronic start button for the pellet stove and within 5 minutes or so the entire downstairs would be whatever temp I wanted.

The amount of heat put out by the pellet stove was regulated by electronically adjusting the fuel feed. It was infinitely adjustable, so I could set it such that it would keep delivering the same amount of heat all day if I wanted. (It had three buttons/adjustments...on/off, fuel feed, and fire-starter.

In the dead of winter when there was snow on the ground, I'd put the pellet stove on its lowest fuel-feed setting and just leave it on all night. In the summer I never had it on at all.

As a bonus, the pellet stove had a nice glass front, so one got radiant heating through the glass, convection heating through the stove's air tubes, and had the pleasure of a real fire to watch if TV got boring and one sat in the recliner just reading a book and/or listening to music. (I also used to sit there a lot with my box full of topo maps, and plan hunts to come.)

Worked great for me.

We just had a new artificial log fireplace set installed with glass folding doors. Amen on the radiant heat. With that and the fan on above, I'm a happy camper.

Now my main problem is that every day my wife asks me to turn the fan off. I guess if I outlive her I'll get to do what ever I want with the fan, up until then, I don't think I'm in charge.