Has anyone here switched to a high efficiency furnace in the last few years? my gas furnace is now outdated and was wondering how much of a difference switching to a high efficiency would make....sales guy showed me a chart which said I'd save about $600-700 a year, but I'm skep-tee-kal. Anyone switch over?

Shawn (real80sman) is an expert. My oversimplification of what he told me is that it depends upon how long you plan to stay in your house. The longer you stay, the more easily you can justify upgrades, including increased efficiency. I'd send Shawn a PM.

I'm on my second super-duper-high-efficiency furnace. My impression is that you are better off spending the extra $$ on insulation and drapes, unless you want the super-quiet super-electricity-efficient servo fan that some of them come with.

My first was a Lennox which was too expensive but worked really well (even though I ended up getting one size larger than I needed, my fault, long story), the second was a (Bryant ? something starting with B) which has worked well but which seems to have a less efficient & louder fan.

My recollection is that there are basically 3 levels - 80% efficiency, ~90% efficiency, and ~95% efficiency. If that's still the case, the 90%'ers seemed like a good deal if your furnace runs a lot during winter, but I wouldn't bother with the 95%'er (despite buying 2 of them ;)).

If your winters are moderate then it's hard to justify spending a lot more money on efficiency. You're going to save maybe 12% of your annual heating bill going from an 80 to a 90, so saving 600/yr implies that your heating bill is 5000/yr (which sounds high to say the least).

One other obvious point -- smaller furnaces running longer tend to make for more comfortable houses and lower fuel bills. If you size the furnace to keep your house toasty on the "coldest day in 5 years" that's probably bigger than you need... next time I would go with something sized to "keep the house comfortable on the colder days running most of the time" and put on a sweater or light a fire on the occasional freeze-ups. I guess having the furnace burning relatively more of the time would translate into a shorter heat-exchanger life but I've never actually heard that discussed.

Ten years ago, I switched from a standard furnace ($1800) to a high efficiency one ($2500) and it was well worth it.

My house was so hard to heat, that I employed a kerosene heater at a lower level to help heat it. Gas bill was running around $200 a month in the winter plus about $80 for kerosene.

After switching furnaces, I no longer need to run the kerosene heater and my gas bill was cut in half. Since then gas has climbed, but the new furnace was well worth it.

Thanks guys. My gas bill in recent years has been around $1200 to $1500 annually(also runs hot water heater), so I can't really see how getting a high efficiency furnace is going to nearly cut that in half. I've been told that the high efficiency furnaces are more troublesome than many of the older units on top of that so I'm leaning towards keeping what I've got, despite it being "outdated".

Hmmm....now I just read Brian's post.....

So far, in (9 years, not 10), I've never experienced any problems with the furnace. I've never had it serviced, but probably wouldn't hurt.

I purchased the Trane XV90 a couple years ago, along with a Lifebreath HRV. If you have the finances, Adrian, I'd really consider a HRV; pretty sure they're code in all new homes now.

If I was purchasing a new furnace or HRV, I'd get the more efficient ECM motor.

Yep, same here, absolutely no problems in probably 5 years (not a couple I guess). My furnace cost $5000, but I didn't care about the savings over time and whether I'd gain it back, it was solely based on lessening my footprint.

It's been a while since I had a furnace put in but back then the cost of the unit was far to high to make up the difference in savings. I went with the 80% efficiency unit.

I think I would spend some money on a house evaluation and see what they say about the efficiency of your insulation, heating etc. and go from there.

http://www.homeperformance.com/energy-audit-home-eco-energy-auditors-ontario-bc-canada