[mmessina1]

Hello, I'm new here and to HVAC, I just want to say that this is a great forum for Home owners and professionals and I'm glad that I've found it!

I moved into a new 3-Storey townhouse (plus basement) just under a year ago, and time has come for me to tally all the warranty repairs that may need to be done. One thing however has been on my mind, I do not have a cold air return on my uppermost 3rd floor. I would like to know if it is required.
The heating system is good, fairly even throughout the house, for the winter, but I find that I need to keep the furnace fan running almost always to keep the temperatures fairly equal on the 3 floors. Especially now that the sun is much warmer. It stays very warm (and a bit stuffy already) on the upper floor and almost too cold on the lower. I do have a thermostat that has a ventilation feature that cycles the fan more often than on an 'auto' setting, but the temp. difference is on the uncomfortable side. The T-stat is on the 2nd Floor basically in the middle of the home.
I live in Ontario, I'm wondering if there is a requirement for an air-return on my upper-most floor? Or is it a design specific requirement? For some reason I think it should be required, I want to make sure before I go to my builder asking about it. I'm pretty sure it can be done easily if that is the case.
I should mention that we don't have A/C yet but the home was built with 'provisions' in the ductwork for central air, according to our builder. Any insight would help greatly! Thanks very much!

 

[beenthere]

If your going to get A/C, you'll want a return on that floor.

 

[Wildie]

I live in Ontario also!
I had a single detached, 3 floor home once! It was an older home that required a lot of renovation.
One improvement was new furnace. I decided that a 2 speed fan motor would be a good idea, so had one installed on the new furnace.
The first winter I left the low speed fan on all the time! The next winter, without saying anything to my wife, I left it off, to see if she would notice any difference!
One day, she commented that the house heat was uneven, and was wondering why?
I pleaded ignorance, turned on the low speed fan again, without her knowledge awhile later!
Then, a few weeks later I asked if she had noticed any coldness lately? She said that it seems to be normal now!
The moral of the story is that in a multi-level home, continuous circulation of the air is necessary, otherwise the heat will flow to the upper rooms, leaving the lower levels cool!
In the upper-most level of this house, there was no cold air return as the air returned down the stairwell.
To ensure that there is always circulation, there must be enough space under the bottom of the doors to allow the return air to flow out of the room.
The standard room air supply duct has a cross sectional area of around 20 square inches!
So a 30" door would need a space of about 5/8" at the bottom for cold air to return properly!

 

[mmessina1]

Agreed and Builder confirmed

I agree about having the return on the top most floor. It was missed when the home was built. I contacted my builder and they confirmed it with the HVAC company that it should be there. I thought so - I was in the house before the drywall was up and noticed that the floor on the upper level was notched leading all the way down to the basement return duct.
I agree with running the fan as well. We dint have a multi speed fan furnace installed but our thermostat did a good job of ventilating the home in the winter because it would cycle the fan often. The difference is now that the sun comes in the upper floors get much warmer and the lower are very cool. Its funny I did the same sort of test with the t-stat on auto, fan on, and ventilate to see if my wife notice too. I know I noticed!
2 Speed fan that is a good idea. Did that come with the furnace or can you just install it after the fact, i.e. change the motor in the furnace? I would definitely keep it on if it ran at a lower speed. I should figure out the wattage of my fan motor if it is low I'll just keep it on. I did do that last summer since we don't have A/C yet. I'm just concerned with energy consumption too. However I was told by our builder that we would save in gas what we would use in electricity if not more savings. Can anyone confirm that?
Thanks for the insight!

 

[beenthere]

Depends on your rates.

And the blower motor.

Your blower could be drawing 200, or 400 watts.

 

[Wildie]

I doubt that there is any consumption savings, other than if the thermostat is in a lower level and the heat kept rising up. This could, perhaps make the furnace run more!
To me, comfort is the first criteria!