furnace blowing all the heat up the chimney

[mkirsch1]

I'm tired of people telling me that there's nothing wrong with my furnace. There is something wrong with my furnace.

It's a 10-year-old Amana 45,000 BTU, 80% efficient unit in a 1300 square foot ranch style house. This is my 4th winter in this house, and I'm sick of being limited to one habitable room all winter.

The air coming out of the vents is cool, around 70 degreees according to my thermometer. The exhaust to the chimney is smokin' hot. The plenum does not get perceptibly warm.

I change the filter regularly. The old filter comes out visibly just as clean as the new filter I put in. There is plenty of airflow through the unit, as I can feel the cold draft hit my feet from across the room when the furnace kicks in.

The flames are steady and clean blue.

I have to close off all the bedrooms and heat only the living room and kitchen during the coldest months, otherwise the furnace would run

24/7 and the temperature would never get above 62.

The pros say there's nothing wrong.

[Lefty]

Something's wrong, but you did'nt say where you are loacted. In my area, you may need a furnace of 65,000-77,000 input to do the job for that house. And it sounds like your blower may be going way too fast. All are really guesses though, given the information it really takes to make a proper size analysis. You need tro try another pro; especially one who will look at the whole building, as well as the heating plant.

HTH, Lefty

[ransley]

You do have AC right, have you actualy looked at the AC coil, my neighbor got a house where the AC coil passed no air it was so clogged, but you still need a Pro, not the hacks youve had out for beer money.

[DT]

Boy, it sure doesn't seem right. I have a 10 year old, 80% efficient

60,000 btu Armstrong furnace for my 1500 sf house in northern Ohio. It puts out 115 degree air at the register closest to the furnace. The double walled flue is hot, but I can place my hand on it. The plenum is, of course, quite hot. I insulated it with high temperature fiberglass.

The house is well insulated with ducted returns and easily heats all rooms over 70 degrees in 15 below zero weather, and only runs about half the time under those conditions.

For starters, is the rerun air ducted, or is it an open return system?

[mkirsch1]

I'm located in Rochester NY for the record, and I do have central air.

There are two ratings on the furnace, one is 45,000BTU and the other is 61,500BTU, but the furnace was made in Quebec and everything written on it is in FRENCH! Online translators were no help in figuring out what the tag says...

[dpb]

[e-mail] wrote: ...

Undoubtedly there's somebody on group that could decipher the amount of French on an equipment tag...

Failing that, undoubtedly there would be translation in Amana documentation on their site???

[EXT]

45,000 output. Whatever the rating, you need someone competent to service the furnace.

[Jules]

Can you get a thermometer into the plenum at all and check there (or at least whatever register's closest to the plenum)? Our system loses an insane amount of heat in the ductwork and there's about 40 degrees difference between the register nearest the furnace and the one furthest away (I did post actual numbers the other week, but can't remember what thread that was in, and I don't have them written down)

Never tested the exhaust temp on ours. Maybe they always run hot at that point.

Just wondering if your problem's the furnace or the ductwork...

[dpb]

DT wrote: ...

More to the point might be are the hot air runs insulated and/or in unheated spaces (like attic/crawlspace) or is there a break somewhere (like a flexible boot at the plenum outlet?) or a closed internal damper or, or, or, ...???

--

[mkirsch1]

I used an infrared thermometer on the vent near the middle of a heating cycle when the air coming out felt the warmest. The temperature was in the low 70's.

Ductwork is all uninsulated in a full basement.

[mkirsch1]

The return air is ducted.

[Van Chocstraw]

Your stack controls are out of adjustment. The blower should cut off at

1. It should cut on at 100.

[dpb]

[e-mail] wrote: ...

Well, DOH!!! Nice and toasty down there, I'd wager...

--

[Colbyt]

The furnace may be working 100% correct but is way too small for the job you are asking it to do.

I live in a much milder climate, Kentucky, have 2 -- 75,000 input rated units at 80%, one on each level, 1300 square foot per level. All ductwork is fully insulated. They work fine and can recover from the night time set back of 10 degrees until the temp gets down in the teens and then I can not set back more than 5 degrees. 1995 construction, walls R-13, about 8" of attic insulation, brick construction with a full, unfinished, unheated basement.

If your AC works fine and you have good air flow at the registers then a blocked A coil is not you problem. You could have a limit control problem that a hasty tech did not stick around long enough to discover.

[clare]

Standard procedure in a full basement is to use bare, uninsulated ducts. I'm 100 miles or more north of Rochester in Ontario -

50,000/75000 BTU (2 stage) 80% efficiency furnace keeps my 1300 =/- sq ft house warm for under $700 a year.AFAIK it has never kicked up to high rate.The 600 sq ft basement is also heated.

[Stormin Mormon]

I'm in a suburb of Rochester. Want me to drive over, and take a look? Yeah, I know. Everyone on the list says I'm a total hack. I know, I know.

[Stormin Mormon]

It sounds like something is totally wrong. Happy to come over and take a look, if you wish. I'm in the phone book.

[Stormin Mormon]

Probably BTU input and output. It's common for furnace to list input which is total heat produced, and output to the house. Since there is air flow, that's got me wondering. Have to come out and see it, to get some ideas.

[Stormin Mormon]

I knew it! Already people are slamming me!

[Stormin Mormon]

Would be interesting if the duct is broken some where, and the suction from the return air is moving all the air. But, he said the plenum doesn't warm up.