Furnace replacement - what to ask the contractors?

July 17, 2006 6:03 PM

I'm having three HVAC contractors come to my house tomorrow to give me estimates for replacing my gas furnace. What should I look for to identify a "reputable" contractor, and what questions should I ask?

Just for clarification, I'm replacing a 15-year old gas furnace that has a cracked heat exchanger. I'm probably going to get a two-stage, variable-speed-fan furnace. What questions should I ask the contractors, and what information should they be gathering from me? I know that they're supposed to do a "heat loss calculation" but I have no idea exactly what that is or how it's done. Any advice from mefites that have gone down this road (or are HVAC contractors) would be appreciated. Thanks!

posted by gwenzel to Home & Garden (10 answers total)

Heat loss calc? Hmmm. I doubt you need this. They size the furnace based on square footage mainly. Do you have big heat losses that need correcting? A good contractor can help out here too and when you are putting in a new furnace this help is essentially gratis.

You want to know what furnace, how efficient, how big, how much money, schedule, and some contacts of prior satisfied customers. Do you have other issues, such as cold rooms, hot rooms, etc.? Ask about those and how they propose to solve them. Who is getting the permit (it's easier if they take care of it)? After price, the biggest issue with any contractor is quality and schedule. Ask around and see what kind of reputation the contractor has on these issues. Sometimes you just have to go with your gut after interviewing them. The last time I did this I went with a guy who was 5 to 10% higher in price, because I had a good feeling. Perhaps I overpaid, but they did a great job for us.
posted by caddis at 6:21 PM on July 17, 2006

this help is essentially gratis by which I mean balancing your system, insulating ducts and other items related to the system itself. Adding attic insulation or whatever is a whole different story.
posted by caddis at 6:25 PM on July 17, 2006

You may want to ask for a start date in writing.

This could also be a good time to move the thermostat if it's in an illogical spot (ours was at the top of the stairs and got plenty of heat updraft), as well as an opportunity to look into multi-zone control.

For what it's worth, we went with a 'remote control' themostat that we could move around the house to wherever we needed/wanted to set a specific temperature.
posted by matty at 6:34 PM on July 17, 2006

We just got our A/C done, and honestly, if you don't have a good vibe, don't go with them. We had a real scheisty character come in here, couldn't act like a normal person, wasn't really very polite, but was large enough to legitimately undercut the other guys that had priced for us . . . but he just felt skeevy. This is an investment, so treat it like one and don't invest with someone who "feels" questionable.

Other than that, do what you can to compare apples to apples, and get it in writing. We found that most of them were within a grand of one another -- what you're *maybe* buying is a relationship with the company, after the actual uint and service.
posted by Medieval Maven at 7:02 PM on July 17, 2006

If you do not already belong to it being a member of Angie's List was invaluable during all my remodelling. Most contractors want to get on the list and the list was reliable in finding out about shady operators. Also take a look at the remodelling forums at Garden Web. Which is the great hive mind of people obsessed with home repair. Good luck.
posted by jadepearl at 7:21 PM on July 17, 2006

yeah: "invest". You're buying 10 or 15 years of appliance: choose a contractor that way.
posted by baylink at 7:31 PM on July 17, 2006

I would look for a contractor who doesn't oversell you a furnace. I had originally planned on getting a variable-speed furnace as well, but the womoan who finally got my business was the one who came in and told me that that would be a waste of money. And she was right - we got a single stage, AC motor furnace which did a beautiful job last winter. Of course, that was compared to a 37 year-old furnace, so it wasn't hard to beat. (I got this done early this year)

Still, a two-stage, variable-speed furnace may be overkill if you do not have a very modern/very well insulated house. The lower heat/blower settings may not be all that useful, depending on your situation.

Also, the lowest bidder is not always the worst job/equipment. Sometimes you get lucky and get a competent contractor who just happens to need to fill a gap in their calendar and will make you a deal.
posted by GuyZero at 8:53 PM on July 17, 2006

I would ask for references and then actually check them.
posted by Julnyes at 9:11 PM on July 17, 2006

The low speed is good for evening out the differences in temperature between basement (if you have one and main floor. Good to keep the basement warm in the winter and as a free source of cool in the summer.
posted by Mitheral at 8:00 AM on July 18, 2006

Yes. If I had it to do over again I would have gotten a two-speed model.
posted by caddis at 8:43 AM on July 18, 2006