are newer furnaces more efficient?

Originally I had planned on getting the furnace replaced last summer and when I asked for advice here, Goodman was the most recommended. One of the reasons was that a "do-it-yourselfer" such as me would be able to repair it. I inspected the unit and doubt if anything should present a problem. The parts are guaranteed for ten years and since I'd replace them myself don't think it's going to cost me a fortune to maintain.

In the 35 years I've been in my house I've done 100% of the appliance repairs myself. Compared to the industrial equipment I worked on for my job, home appliances are not a big deal.

As to the old "they don't make them like they used to" adage.

Yep, my old oil-burning furnace definitely had better sheet metal than the one I just had put in. OTOH: If that oil burned could go six weeks without breaking down or needing some type of maintenance, I was lucky.

BTW: I will get a fairly decent rebate from "Focus on Energy"

It looks like anyone who gets a high-efficiency furnace qualifies for a $150 rebate, but since I'm retired my income will qualify me for a higher rebate. Will have to submit the paperwork to know the amount...but it's up to $850

Reply to
philo
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micky wrote: "Are you somehow giving the measured efficiency or the rated one? "

Measured - our provider measures it every other year or so, during yearly maintenance.

Reply to
thekmanrocks

micky wrote: "Sorry, I don't know what hydronic means and it's not a word the poster"

Hydronic simply means hot water - not steam, not air, hot cocoa, or any thing else.

Reply to
thekmanrocks

How does he do that?

I can see putting some accurate gauge in the oil supply pipe. Does he do that?.

But how does he measure the heat output?

Reply to
micky

Proper terminology. Furnaces heat air. Boilers heat water. If everyone uses the proper terms, especially on a home repair group, it avoids confusion.

There are some specialized units that use hot water to heat the air, thus they are a hot water furnace, but the end product is heated air. Water is just the heat source.

Reply to
Ed Pawlowski

That is a boiler, not a furnace.

A heating system that heaters water and circulates it using baseboard or radiators is a hydroid system. Hydro = water, liquid, fluid.

Reply to
Ed Pawlowski

Hydronic system. Damned spell checker, clicked the wrong button.

Reply to
Ed Pawlowski

From the context, a hot water furnace burns hot water. Eco friendly, puts out hydrocarbons when it runs.

- . Christopher A. Young learn more about Jesus .

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Reply to
Stormin Mormon

What exactly makes a 98% one high maintenance as opposed to 94, 95, or your 96%. I would think the essential difference would be that the higher efficiency would use a slightly more efficient and costly heat exchanger.

Reply to
trader_4

People didn't believe you because you were wrong. I replaced my nat gas furnace back in 2010 with a 93%. There were other units available that were even slightly higher. All of that was available from all the typical furnace manufacturers. 90%+ furnaces have been available for at least a decade, probably a lot longer. The essential big change was when they went to *condensing* direct vent ones. There was a lot of energy in that steam that went up the chimney.

Reply to
trader_4

I saw similar when I replaced my 27 year old nat gas furnace with a 93%.

Reply to
trader_4

micky wrote: "How does he do that? "

I do not know. All I saw was the sticker on the side of my boiler with fields "Checked by"' "Date", and "Efficiency", filled in by different technicians over the years.

Reply to
thekmanrocks

I'd be happy to see data that supports that. There are a lot of people with fuel bills of $1500 a year. If they save 20%, that's $300 a year. In ten years, it's $3000, about 50% more than the cost of the furnace equipment to begin with. I replaced my 27 year old nat gas furnace

4 years ago and have been saving 40%+, Ed reports similar with a boiler. I'm saving about $300 a year. The most costly repair, would be the heat exchanger. All the systems I looked at, the heat exchanger was either warranted for 20 years, lifetime, etc. Not saying you won't have to put some money into an aging furnace, or that a high efficiency one doesn't have more parts that can fail, just that I haven't seen any real data to support that it's going to wipe out staying with a lower efficiency furnace.

Yes, there are more safety devices on modern high efficiency furnaces, so there is more possibility of one failing. But I also wonder how many safety switches there are on a new 80% furnace now too? I've got 4 years now with a Rheem 93% furnace, not a single problem.

This year was another $610 for a draft inducer.

If she paid $610 to have a draft inducer installed, I'd say the more likely problem is that she has a service company that is screwing her. I'd also point out that a lot of stuff today doesn't last as long as it used to. I think in many cases folks are comparing the lifecycles of 40 year old furnaces to modern ones. I'd be surprised if a new 80% furnace lasted as long as one did bought in

1970 too. In other words, you have to compare the problem rate of a new 80% with a new 93%+.
Reply to
trader_4

Similar here with my 93% Rheem. There isn't anything exotic there that I can't fix myself.

+1

That helps too, same here.

I got the fed tax credit back in 2010, which was ~$1200. Those credits reduce the cost substantially and there isn't but a few hundred dollars difference in the cost of a 93% furnace compared to an 80% one.

Reply to
trader_4

I put in a coleman THE about 25 years ago and the efficiency was 90%. This unit was inexpensive (actually designed for a housetrailer, but it was big enough for our house). I think the trick was they passed much more air through the heat exchanger. It needed no chimney, but the air coming out of the registers actually felt cool, but there was so much of it that it heated the house. My feeling is that you can compare efficiencies, but you cannot calculate payback periods because gas prices vary and weather varies. All you can do is keep track of your costs and calculate payback period retroactively. Anyway, because of abnormal weather and changes in gas prices, that unit paid me back in just over one year. I don't expect to ever match that performance again. It had some design problems and after many years, I was seeing the repairman too much. So this year I replaced it with a Bryant said to be 95.5 efficient. The biggest change I noticed is that it has air from outside the house pumped in and used for combustion. As a consequence, we don't have outside air in the house, and the air coming out of the registers is much warmer. It also has a high efficiency multi-speed blower which comes on at a lower speed during some of the furnace's idle time to circulate the warm air in the house. I haven't had it long enough to calculate how much, if any, it will save us, but the increased comfort is worth a lot. Now I'm looking at adding a heat exchanger to get some fresh air into the house

Reply to
No name

On 01/28/2015 9:58 AM, No name wrote: ...

Unless you change something else drastically, the Btu demand to heat the house will be the same so two units of different efficiencies will produce those total Btus with the relative amounts of fuel that their relative efficiencies indicate to within a (quite) reasonable approximation.

Hence, one can do a reasonable estimation of payback period knowing past history and costs. One can't know precisely what a given winter is going to bring, granted, but that's not of real concern in getting useful estimates.

Now, if one changes the parameters by also adding/upgrading insulation or increasing the footprint of the house by adding in previously unheated/marginally-heated areas or is switching from a boiler/steam radiator to forced air, then, sure; there's enough difference as to make the computation much more difficult and certainly less accurate.

But, presuming from the question as posed that this is simply a drop-in replacement/upgrade request, I'd say he'd get a pretty good estimate simply by ratio of the proposed unit efficiency to the existing. Now, getting a reliable number for the current unit may be the biggest uncertainty altho 50-60% is probably good enough for the purpose.

I've not priced recently, but when we upgraded/replaced here about three/four years ago now, the price differential between the ~95% and the higher units started to really escalate. Same as with the SEER ratings on the AC side. The payback can get really long if one goes to the extreme. We ended up w/ a 95% Carrier and while I've not compared, the difference is notable. Of course, NG prices have peaked and dropped at least a couple times over that time period, too...

Reply to
dpb

Usually a probe in the stack with a meter. I've seen it done but have not done it myself. They can also read what gasses are in there since on industrial boilers you usually have to keep the EPA happy.

Reply to
Ed Pawlowski

s after the furnace is 10 years old or so.

I was skeptical when the advertising said you can save up to 40% on fuel use. I figured if I save 25% to 30%, I'd be happy I kew what my oil consumption was the the past couple of years so I had numbers for comparison

After the first year, I calculated the oil use based on degree days. At

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I was able to get the historic data also. I was pleasantly surprised to see that I came very close to the 40%. I even contacted Energy Kinetics, makers of the System 2000 boilers. They did their own audit and concluded I save 39.2%.

In my case, the old boiler was about 30 years old and on the way out soon so I had to do something. It was also good timing with Federal energy credits, state rebate and state 0% financing. It would have been foolish to do nothing and pour money up the flue.

So far, it has been trouble free, no repairs. Once last winter I had to cut the power, let it restart and it has been OK since.

Reply to
Ed Pawlowski

trader_4 wrote: ...

our experience was that within 12 years the heat-exchanger went and even while the company did replace it we still had to spend quite a bit of money to do that. we also had a lot of problems from the ignition system. whatever part it was they were getting was coming from Mexico and it failed each year. finally we asked them to find something else and it hasn't been any trouble since.

our heat costs run between $600-1200/yr on propane (normally the thermostat is set at 58-60F). i think our unit is rated at 95% or so. 98% would have cost us about $500 more when we replaced the exchanger. we've also had to replace the fan.

i sure wish this place had been set up for more passive solar as right now this mid-winter cold day the sun is shining nicely and we could be avoiding some of the expense of heating (for hot water too).

songbird

Reply to
songbird

If you don't mind, which brand did you buy, and what was the approximate installation cost?

I've got a 1988 Burnham gas furnace in my 1911-vintage and very leaky

1400 sq.ft. house. Last month's bill indicated 224x100 cubic feet of consumption.

It's still running fine, but wondering if a more efficient furnace would make much of a difference.

Reply to
John Albert

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