Once upon a time, back when Eisenhower was president, a nice forced-hot-air furnace looked like this — well, picture it without the duct tape holding it together.
Fast forward 55 years, and it had become loud, rattly, clangy, very loud, did I mention loud, and inefficient. It would prompt older HVAC guys to mutter, “Haven’t seen one like this in a long time,” and prompt younger HVAC guys to just plain laugh. Most ominous of all, last time it broke, it prompted the HVAC guy to say, “You’re lucky I had a part for it out in the truck, because it’s the last one I have, and they don’t make them anymore.”
So last fall we finally looked into replacing it. We knew the electric company would offer some rebates if we got a home energy audit done first, and so we did. Not only would we qualify for rebates on the furnace and air conditioner (which in the current unit was permanently broken), but we also got a rebate for a programmable thermostat and a free light bulb, and qualified for free air sealing and a 75% discount on insulation. Sign us up!
The air sealing was performed by some subcontractors for the electric company. The guys spent a few hours scrambling around mostly in the attic, sealing up gaps with expandable foam and using sheet metal to cover larger gaps. It turned out half the air that the furnace had been heating to move through the house was being drawn from the unheated attic! They took care of that. In the end, the cat was thoroughly wigged out by the banging noises, and our air leakage (as measured by their blower door tests done before and after sealing) had gone from 2950 to 1550 — cut nearly in half.
The insulation was performed by a different subcontractor, and the deal was that the electric company would pay for 75% of the cost up to $2000. So the guys spent a few hours up in the attic, putting an additional 6″ of fiberglass insulation down on top of the insulation already up there, the cat got thoroughly wigged out again, and I only had to pay $535. This is less than it would have cost me to buy the insulation at the hardware store, never mind all the hassle of installation. And since some of the previous insulation was stuff I’d added several years ago, I do know exactly how unpleasant it is to lay down insulation in that attic. The house is metal-framed, and the roof trusses are 4′ apart. And there’s no floor under them, just the sheetrock of the ceiling, so you really do have to take 4′ steps to move through that attic, while crouched down lugging bales of insulation.
The programmable thermostat which I bought online billed itself as “easy to install, takes 30 minutes.” I guess they’re right. It took me about 5 minutes to do all the wiring, and 25 to drill holes into the studs (see “house is metal-framed” above) to mount it on the wall.
And finally, we did buy a new furnace and A/C unit, plus a new double-layer oil tank since the old one was looking rather iffy. We had looked into switching to gas, but both logistically and financially, it wasn’t practical. (When 3 different contractors all seemed a little confused about how they’d run gas lines into the house and run a furnace condensate line out, and came up with 3 different, “I think this might work” answers, we gave up.) The old furnace had to be cut up into pieces to be hauled out of the house, which was such a fiendishly cumbersome and loud process that one HVAC guy got some cuts on his hands, E got a little nervous, and the cat was so traumatized that he refused to walk down the hall past the furnace area for a few days.
I could stick in a picture of our shiny new furnace here, but hey, it looks like a modern shiny furnace and it’s about half the size of the old one, so you can just picture it without me fussing with the camera. If you want to see the oil tank, it’s here.
And after all this work, the house feels noticeably warmer and less drafty. The furnace is quieter. The cat has gotten over his fear of the furnace. And based on our heating oil bills for the winter so far, we appear to be using half as much oil as in previous years. Degree-days (ie, need for heat based on the weather) show that this season has run very similar to last year, so it’s an easy comparison.
Up front cost: $9100 for furnace, A/C, oil tank + $35 for thermostat + $535 insulation = $9670.
Discounts: $400 for furnace rebate + $400 for A/C rebate + $25 thermostat rebate + $1500 federal tax credit + $200 coupon from the newspaper for the HVAC company that did the furnace = $2525.
Net cost: $7145. It’s hard to guesstimate a payback time, but if heating oil runs over $3/gallon it will be less than 10 years. The new furnace uses less electricity than the old one for the blower, so that will drop the payback period even further.