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Morrow
Time to replace gas furnace, opinions?

I was recently having my 23 year old Trane furnace serviced and was told (and shown) that the heat exchanger was cracked. Long story short its time for a replacement.

With the tax credit and incentives I was looking at the high efficiency units to replace.

I have no idea what brand to go with. Are there any recommendations out there? I am looking for cost effective and reliable, not too concerned with bells and whistles. In fact, if it wasnt for the rebate's I would just throw in another 80% unit.

Also, are the higher efficiency units more complicated therefore having a higher risk for problems?

Oh, my house is 1.5 stories (cape cod style) and is apprx 1500 sq ft. No heatpump or AC and no plans to install.

Thanks in advance.

NashuaTech
Re: Time to replace gas furnace, opinions?

Morrow:

I would try to encourage you to approach a furnace replacement from a different direction: given that there are quality high-efficiency units among the top brands such as Carrier, American Standard, Trane, York, Weil-McLain, Rheem, Thermopride & others, your focus should be on trying to select among the BEST INSTALLERS IN YOUR AREA.

You'll have to burn some shoe leather, but ask neighbors, friends & relatives who have a gas furnace who they hired, & the results good or bad, and the service performance after installation.

Check the Yellow Pages under "Heating Equipment" and go down to the countermen at the heating parts supply houses in your area to get a recommended installer.

Another resource is real estate agents who own & rent houses & apartments or house-building contractors---they have to make these decisions every day & know the reliable service people.

It's important to avoid furnaces that have too many specialized (proprietary) parts that would be hard to get on short notice if the furnace breaks down on a cold winter's night---Carrier, Lennox & York often fall into this category, but it depends on your area.

Definitely ask the prospective installer about parts availability for the unit he intends to install in your house---make sure the prospective installer does a HEAT LOSS CALCULATION where he goes around your house to measure windows, asks about exterior wall insulation, etc., and puts the results into a computer Manual J program to get an accurate idea of how many btu's/hour your house needs to stay warm.

A very rough estimate for an average 1500 sq.ft. house with an average heat loss factor would be 1500 sq.ft. X 40 = 60,000 btu/hr for the size of the furnace---this is a very rough estimate & the number depends on your location in the U.S., type of building, number of windows, etc.

Thus, have a HEAT LOSS CALCULATION (manual J) done to determine the size in btu's/hour the unit should be---installing too large a unit will waste a lot of gas---make sure your insulation in exterior walls & the attic is up to snuff (R19 in walls, R40 in attic)---make sure all your windows are tight or you have storms.

Get at least 5-6 written estimates (bids) from different installers (Yellow Pages, "Heating contractors") & include oil dealer installers, who are licensed to install gas equipment as well & often charge less.

If it was MY house I would put in a condensing high efficiency furnace that will give you a 95% fuel use efficiency or better from a brand listed above.

http://www.aceee.org/consumerguide/heating.htm

Morrow
Re: Time to replace gas furnace, opinions?

Wow, thats some good information. Thanks.

Its not an easy decision as I am a car guy, not a furnace guy. I've received 5 bids already ranging from $3700 - $5200 for the high efficiency unit.

Some of the HVAC installers are easy going well others are a little more pushy ("need to make up your mind by the end of the month as the rebate will expire")

I would rather wait and take my time as its the end of June and wont even need the furnace for another 3 months or so (Oregon).

I liked the price and warrenty from the Carrier contractor, however it looks like carrier doesnt make a 95% unit of their own so they use a Comfortmaker. Any opinions on this unit? It has a 10 parts and 5 year labor warranty.

I definatley did not plan for any of this.

Thanks again.

NashuaTech
Re: Time to replace gas furnace, opinions?

Morrow:

You're doing the right thing ----don't take any "pressure" from any prospective installer---it's an indication that you'll have trouble with them later on down the line---choose someone who is courteous & respectful---as you said, you can spread this search out for 2 months if you have to---don't buy until you're comfortable with the bids & choice of equipment.

Not familiar with Comfortmaker, but I am almost sure they are also made by Carrier---Carrier has at least 8-10 brands they have bought out over the years: Payne, Bryant, Day & Night, Arcoaire, Heil, Tempstar, & perhaps Comfortmaker.

My list for Comfortmaker lists a gas-fired unit at 95% AFUE as model numbers beginning with C9UHX, and also a 94% AFUE unit listed with model numbers beginning with VNK.

Carrier lists its Infinity at 94 to 96% AFUE (58MVP, 58MVB, 58UVB), and its Comfort 92 at 92-96% AFUE (58MXB).

Bob Gabrilson
Re: Time to replace gas furnace, opinions?
Morrow wrote:

I was recently having my 23 year old Trane furnace serviced and was told (and shown) that the heat exchanger was cracked. Long story short its time for a replacement.

With the tax credit and incentives I was looking at the high efficiency units to replace.

I have no idea what brand to go with. Are there any recommendations out there? I am looking for cost effective and reliable, not too concerned with bells and whistles. In fact, if it wasnt for the rebate's I would just throw in another 80% unit.

Also, are the higher efficiency units more complicated therefore having a higher risk for problems?

Oh, my house is 1.5 stories (cape cod style) and is apprx 1500 sq ft. No heatpump or AC and no plans to install.

Thanks in advance.

You didn't say if you had a basement? I would recommend (depends on the insulation) a 60,000 or 80,000. A two-stage furnace is nice with a 2-stage stat (vs the timer on the furnace). I like a variable-speed blower, but you don't have nor want A/C so to save money you could forfeit that option.
Goodman/Amana makes both. Good luck.

JLMCDANIEL
Re: Time to replace gas furnace, opinions?

I don't believe that the technology of the HE furnaces has reach a point of reliability. Generally the amount of service and the cost of parts far exceeds the fuel savings. 80% units on the other hand are very reliable and they are generally simple enough for DIY service and repair. That's just my personal opinion.
Jack

Bob Gabrilson
Re: Time to replace gas furnace, opinions?
JLMCDANIEL wrote:

I don't believe that the technology of the HE furnaces has reach a point of reliability. Generally the amount of service and the cost of parts far exceeds the fuel savings. 80% units on the other hand are very reliable and they are generally simple enough for DIY service and repair. That's just my personal opinion.
Jack

Wouldn't you agree that they both have (almost) the same parts?
The 95% have more pressure switches but they are dependable.

JLMCDANIEL
Re: Time to replace gas furnace, opinions?
Bob Gabrilson wrote:

Wouldn't you agree that they both have (almost) the same parts?
The 95% have more pressure switches but they are dependable.

Yes, they do have many of the same parts. It reminds me of the Olds diesel engines that used many of the same parts as the gasoline engines.
Jack

Bob Gabrilson
Re: Time to replace gas furnace, opinions?

Sorry, I totally missed the point. However, I'll take higher efficiency any day. I've had my 95% AFUE, "variable-speed" furnace running for 18 years (never serviced, I'm embarrassed to say).
My only regret is not going with geothermal. But I didn't know much about it then and I think the technology is much improved now also. Just me.:)

pearsbent
Re: Time to replace gas furnace, opinions?

After speaking with a number of local contractors regarding replacement of the furnace, I have narrowed the field down to bids from three companies. As the cost difference between an 80% and a 95% furnace is negated by the federal tax credit for energy efficiency, all bids are for 95% AFUE two-stage (or better) furnaces. Most ducting will be replaced to allow for proper air flow / static pressure and for the ability to add air conditioning down the road. The following is a spreadsheet outlining each proposed system..

Sten
Re: Time to replace gas furnace, opinions?

I'd have to agree with Bob Gabrilson, years ago Goodman was at the bottom of the list but have come a long way since then and are very reliable.

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