Needing to Replace Furnace

15 years ago

Today I woke up to find out our furnace is soon to die. Pretty much everyday, the furnace comes on twice in the 1/2 hour I'm getting ready for school. The second time is usually 6:50ish. Today it didn't come on. I looked that the thermostat, saw that it said 67(supposed to be 68) and that it said HEAT ON. This means that the house is 1degree below the set temp. and that the therm. is calling for heat... BUT the furnace wasn't on.

About 5 minutes later, I took the cover off to find the exhaust blower humming and the motor casing hot. The bearings on it are bad. They've been making noise and showing signs of death for most of the winter, despite being oiled periodically. The problem is whoever designed it is an idiot. only one side of the motor's bearings are oilable. When they seize up, you need a new blower unit. :x We managed to get it freed up and one side oiled well, but it's loud and isn't going to last much longer.

The furnace is a 94% High efficiency Armstrong unit. Nat. Gas, direct vent, forced air, 45,000 BTU. Still considered very efficient, but it's 15 years old and the last time it didn't work, the tech who inspected it stated that the secondary heat exchanger was clogged with rust and would need to be replaced. We're thinking now is the time to replace the HVAC system.

I know some of you guys are knowledgeable in this kind of stuff, and I'm wondering what kind of advice you have for us???? The A/C unit (I'm assuming) is the age of the furnace(15 years). It works fine though, well, it worked all last summer anyway.

The house is in Southeastern WI, built in 1949, walls are insulated, two stories, about 1500 sq. ft.(do you count a second floor in the sq. ft. number? I did). Walls ARE insulated(I think).

Do you think 45k BTU sounds about right for a furnace? Should we have the A/C replaced with the furnace? Any recommended brands and others to avoid? I've read some stuff about hybrid heat, uses a heat pump down until about 40*F then switches to gas. Our electric is pretty cheap compared to others' rates I've seen. About $0.11/Kwh, and gas is about $0.93/therm. Would a Hybrid system make sense for us? How much more is this usually then a normal gas furnace? What about variable speed blowers and variable flame systems?? Are they worth it? How much extra for things like that? The furnace will be direct vent, nat. gas, and 90%+ efficiency for sure. After that, it's all up in the air... All opinions, thoughts, comments, advice are welcome.

Thanks,

Adam

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Comment (1)

fandlil
15 years ago
If you have the leisure to consider various alternatives (assuming you're not so uncomfortable you need to get a new system without delay), you should explore the possibility of getting a new system that qualifies for the energy efficiency credits put in place by the Obama Administration. I cannot give you details about that. But our next door neighbor put in such a system just about a month ago, and he qualifies for a sizable tax credit Plus you have the benefit of a state of the art system that will use a minimum of fossil fuels.

Another suggestion: if you go to the Energy Saving Forum on this website (I forgot exactly what it's called), you can get a lot of info about things like geothermal systems. They are costly to install, and they have to be done by contractors who really understand the technology. If they're done right, your heating/AC costs will drop down to a tiny fraction of the usual, even in really cold places like Montreal. But I do not think you should go that way unless you are prepared to spend more up front and you can identify a really knowledgeable contractor who knows about this stuff.

Good luck.
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Needing to Replace Furnace

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fandlil

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