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Cold Second Story--Help!

Our house was built in 1938 and originally had a coal-fired boiler in it. It has since been retrofitted with a forced air furnace, but the ducts are only to the main floor. The basement and half story second floor have supplemental electric baseboard heaters.

My problem is this: How do I get our gas furnace working more to heat the upstairs (and basement, but that's less important)? We leave the door to the upstairs open hoping to catch some of that "heat rising" effect, but it's been pretty chilly up here, and it's only the middle of November (in MN)! We have one ceiling fan upstairs, but it's nowhere near the stairwell.

Our furnace is great, very efficient, we have excellent insulation (our house was improved by the airport commission for sound-proofing, which includes HVAC and noise insulation), but the electric bills for heating half the house are going to kill us this winter.

For the month of October, our electric bill was $120 (all CFL bulbs, and we turn everything off we can), and the gas bill was only $30 (with gas stove and water heater). Somehow we need to get the furnace heat distributed more effectively as electric heat is so much more expensive.

Any suggestions? Would a ceiling fan at the top of the stairs help? Cutting a hole in the floor?

Also, is it feasible to add a duct to help heat the basement family room?

For reference, the second story is a T shape with closets and a bathroom running along the sides of the tall part of the T, with very tall and steeply pitched ceilings. The stairwell is at the bottom of the T, and my bedroom and office are at the top of the T.

Re: Cold Second Story--Help!

The first paragraph of your post is the central issue---the supply and return ducts only service the first floor---you will have to determine if you have sufficient heat capacity in the furnace to heat the rest of the house, and hire a heating contractor to extend the ducting to those areas.

Consult the Yellow Pages under "heating contractors" and have one or two techs come over & size up the situation to see if the ducts can be extended & the estimated cost---get the estimate in writing.

The ducting for forced hot air systems works on the idea of the furnace heating the air inside the furnace, with a large fan blowing the heated air thru the SUPPLY DUCTS to the rooms; there are RETURN DUCTS on the other side of the rooms that return the cooled air back to the furnace to be reheated---this circulating motion of heated & cooled air continues until the rooms are heated and the room thermostat is satisfied, shutting down the furnace.

What is the total square footage of the first floor, the second floor and the basement ????

Look at the front of the furnace & see if there is a name plate/tag on there that indicates the HEATING OUTPUT of the furnace---it should say something, for example, like Output: 60,000 BTU/hr.

Have you had any heating service techs over in the past on this issue; what did they say????

The fact that a previous owner had baseboard put into the 2nd floor indicates there must have been some problem, economic, capacity, or other, in not extending the ducts.

Re: Cold Second Story--Help!

Thanks for your quick response!

You know, I went down to check out the furnace, and I can't find the BTU's on it anywhere! The darn thing has everything still on it--the Energy Guide, every warning sticker and operating instruction possible, the paperwork is all attached, but I just couldn't find the BTU's. It's an 80% Rheem furnace, and was installed in 2005. We just purchased the house this summer, so we have no history with heating it yet.

The baseboard heaters are clearly much older than that. I wasn't expecting some magic solution that would adequately heat our upstairs fully (the foundation sq ft is 1024, the upstairs is the same, but with very steep roof pitches, so the volume is not the same as the main level), I was just trying to figure out ways to bring more heat from the furnace (that is more than adequately keeping up on the main level, so I'm actually not really worried about the BTU's on it) to the upstairs to cut down on the electrical heating. The upstairs also has it's own AC, and it's a stucco house, so cutting places for new ductwork is tricky at best.

For the basement, I can't figure out why they didn't just install a single register. There's a cold air return in the family room, but not a heating duct... That, I would think, is a pretty easy fix.

I want to arm myself with a little more information before bringing in a heating contractor. But maybe that is the next step.

I was hoping someone on here would have some grand suggestion for ways of taking advantage of the heat rising phenomenon in order to pull some more heat up here.

Turning the ceiling fan back on today seems to have helped some.

Is there some secondary heating system that would could have installed that uses natural gas that would be similar to our AC unit? It's the kind that is wall-mounted and the condenser is outside next to our regular central air unit.

Re: Cold Second Story--Help!

The furnace 75,000 BTU's per hour.

Thanks again for your help!

Re: Cold Second Story--Help!


With a furnace capacity of 75k BTU/hr, you have adequate heating capacity to warm both floors, and probably the basement as well.

Wouldn't it be nice to have a toasty warm house on all floors with little or no electric bills for heat?

It can be done, but the only way is to attach some additional ducting to the main supply/return plenums or ducts---perhaps with zoning, duct booster fans, & small diameter ducting that will get the heat where it's needed.

It may be less expensive and less troublesome than you think, but you'll have to get some techs in there to give you estimates on how it can be done & what it will cost---all the estimates are free of charge, and you can get as many as you like before you decide.

It would be a shame to waste the heating ability of a good furnace to heat all of the house by just heating half the house & leaving things as they are now, continuing to run up large electric bills when there's no need for it.


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