Am I getting good advice - replace the AC, not the 21 year old furnace

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URSnshn
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Am I getting good advice - replace the AC, not the 21 year old furnace

Post by URSnshn » Fri Jul 21, 2017 7:58 pm

My 21 year old Carrier house air conditioner has a refrigerant leak. The furnace appears in good condition according to the technician (also Carrier and same age). Both were installed prior to moving in.

It isn't apparent where the leak is coming from and in order to figure it out - it will cost approx $500 to add UV Dye to the system and find the leak or leaks. It would cost $1400 to $2500 (if it needs a coil) + labor at $250 per hour (3 hours?) to fix the current leak(s). A new Carrier would be about $3500
total apparently.

The cost for furnace and air together has to be quoted by a salesman, but the technician was saying a furnace would go for $6500 - $7000 or so if I remember correctly. And the two together would be around $7500 - $8000.

They said the furnace is fine, though they did caution that the air conditioner has leaked (frozen coils, and I saw it) - it sits on the furnace - so there could be some issue that they can't see. Other than that all tested well for the furnace.

Questions:

1) Does this make sense to you?

2) Would you price an air conditioner AND a furnace, even though the furnace is working well at this point because it is 21 years old? I ask because there is substantial savings when I buy both as opposed to buying just the air conditioner. The company who has looked at the two systems has a good reputation, has done work for me before.

3) Surprisingly, I didn't realize the air conditioning wasn't working - I've been comfortable without it. I could simply have it removed, but I wonder about resale value without it.

I'd love to hear what you think.

[edited to add labor cost, and to add the cost info for the air and furnace together]
Last edited by URSnshn on Fri Jul 21, 2017 8:26 pm, edited 2 times in total.

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by Grt2bOutdoors » Fri Jul 21, 2017 8:03 pm

How much would it cost to get both A/C and furnace together?
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URSnshn
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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by URSnshn » Fri Jul 21, 2017 8:24 pm

The cost for furnace and air together has to be quoted by a salesman, but the technician was saying a furnace would go for $6500 - $7000 or so if I remember correctly. And the two together would be around $7500 - $8000.

Added to original post.

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by ResearchMed » Fri Jul 21, 2017 8:29 pm

URSnshn wrote:The cost for furnace and air together has to be quoted by a salesman, but the technician was saying a furnace would go for $6500 - $7000 or so if I remember correctly. And the two together would be around $7500 - $8000.
Did you have any reason to think the furnace has a problem, other than it's age?

And you probably should get some comparison estimates about the costs of one now, one later, or both now.
The combined cost isn't quite making sense, although it could be okay of course. Just double check those prices.

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Rager1
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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by Rager1 » Fri Jul 21, 2017 8:32 pm

I was in a similar situation years ago. I decided to only replace the A/C at the time. Later, when I had to replace the heating system, I discovered it would have been more cost effective doing both at the same time.

At 21 years old, I'd spring for it all at the same time.

Ed

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by BIGal » Fri Jul 21, 2017 8:35 pm

I would get a couple of more quotes and also discuss with friends/family in the area for recommendations on who they have used. 7.5 to 8k seems quite high....but then again, I don't have the details (nor want them) but you really need to "shop around" with that kind of estimate. Replacing a 21 YO system is probably a good idea for efficiency too...it should result in lower utility bills. You may want to call your utility for their input...quite often they offer rebates that could be substantial. Good Luck.

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F150HD
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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by F150HD » Fri Jul 21, 2017 8:49 pm

better the AC fails then heat. like you, I often live w/out AC (clearly depends where one lives). I say take your time, do some research, when you find a good deal on a new entire AC/furnace system and labor, have it installed. I would't just 'fix the AC'. At 21 years, the system has probably already outlived its life expectancy.

Now, if the furnace is running fine, you might think of selling it. You'd be surprised what someone flipping a house might pay for it. Or, some family in need of a deal.

Installed a new furnace w/ a buddy at my home 2 years ago. I put my old 25 year old furnace in the alley and an ad on Craigslist for 'free'. It was gone within an hour.

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by Watty » Fri Jul 21, 2017 8:50 pm

URSnshn wrote:3) Surprisingly, I didn't realize the air conditioning wasn't working - I've been comfortable without it. I could simply have it removed, but I wonder about resale value without it.
You can likely have them set it up so that it would be easy to install and A/C later when you are ready to sell the house, and then the house could be sold with a new A/C system. If you are not likely to be selling the house in a few year then I would do that.

I would also ask about how efficient the old furnace is and how much energy you might save by putting in a more efficient one. It could be that the energy savings would help justify paying for a replacement.

If you are not on a tight budget then a new furnace might make your house a lot more comfortable if it has multiple or variable speeds. I have found that can make a noticeable difference. You don't need to buy a top of the line one with all the bells and whistles but a good mid range one will likely have a lot better features than your old one.
URSnshn wrote:They said the furnace is fine, though they did caution that the air conditioner has leaked (frozen coils, and I saw it) - it sits on the furnace - so there could be some issue that they can't see. Other than that all tested well for the furnace.
It sounds like it would be difficult to replace the furnace if it needs to be replaced in a few years.

I once had to replace a water heater that failed and I had to pay top dollar to get it replaced in a hurry. Since then I have figured that it made sense to replace things like that before they totally died.

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by mortfree » Fri Jul 21, 2017 8:59 pm

If you're not moving out soon I would replace both like others have mentioned.

Try to get 0% financing if that is your thing (and available).

I imagine there is savings in labor by doing both.

I would also like to have the furnace and AC "paired" from the start and get a new thermostat if your current one is old/non-programmable and doesn't have wifi.

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by TLC1957 » Sat Jul 22, 2017 6:00 am

How long does it take for the AC refrigerator to leak out? I had the same problem and for 3 years I just had them add more refrigerate each spring for $150.

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by jharkin » Sat Jul 22, 2017 6:36 am

A few thoughts...

#1. This tech sounds very honest... This was a prime opportunity to upsell you and he didn't take it.

#2 Age alone doesn't mean that furnace will fail soon. Furnaces don't last as long as boilers but even so I've seen lots of homes with functional 30,40,50 year old heating systems.

#3 Appliances are getting less and less reliable with each generation as they get more computerized. Expect a new system won't last as long as that old one did and will break down more often. Many of us resist upgrading for this reason.

#4 A new system will be more efficient but the gains now are into diminishing returns. My MIL has a 90s vintage gas furnace in her condo and it's 96% AFUE. A 2017 system might be 98% AFUE. Do the math on ROI spending $7000 to save $5 a month on the gas... :oops:

If you do go ahead, get multiple quotes and call your utility to see if they have any rebate programs you can take advantage of.

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by Swansea » Sat Jul 22, 2017 6:45 am

If you decided to do the AC only, I check that the unit will be compatible with the air flow/blower of your current gas furnace.

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by carolinaman » Sat Jul 22, 2017 9:12 am

I recommend replacing both AC and furnace, especially if this is more cost efficient. There have been lots of improvements in heating systems in last 21 years. You will get a more efficient and much improved system, saving on heating costs and providing greater comfort.

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by Big Dog » Sat Jul 22, 2017 9:29 am

how efficient are the current burners? how much heat do you use? The leak could be in the house lines, btw. (Our AC does have a slow leak, but the furnace is in the garage in the front of the house, so the cooling lines go from outside the back into the walls and snake thru the attic down to the blower. Added dye, but did not see anything in the outside lines, that was easily fixable. Thus, we just charge it once every couple of years.)

In any event, suggest you post on HVac Talk. Lotsa contractor-experts who share their recommendations with you, and will provide you with ideas on questions to ask. Not for DIY'ers and do not post quotes. Other than than, its a great education for research before you spend $10-15k.

http://hvac-talk.com/vbb/forumdisplay.p ... ntial-HVAC

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by ncbill » Sat Jul 22, 2017 9:47 am

The furnace put in 20+ years ago is probably 80% (or less) efficient.

When replaced my system (gas furnace/central air) with a dual-fuel heat pump/gas furnace almost a decade ago I went with the cheaper 80% non-condensing gas furnace. I live in a mild climate where nearly all heating is handled by the heat pump.
jharkin wrote: ...#4 A new system will be more efficient but the gains now are into diminishing returns. My MIL has a 90s vintage gas furnace in her condo and it's 96% AFUE. A 2017 system might be 98% AFUE. Do the math on ROI spending $7000 to save $5 a month on the gas... :oops:

If you do go ahead, get multiple quotes and call your utility to see if they have any rebate programs you can take advantage of.
Last edited by ncbill on Mon Jul 24, 2017 10:29 am, edited 1 time in total.

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Kenkat
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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by Kenkat » Sat Jul 22, 2017 11:15 am

carolinaman wrote:I recommend replacing both AC and furnace, especially if this is more cost efficient. There have been lots of improvements in heating systems in last 21 years. You will get a more efficient and much improved system, saving on heating costs and providing greater comfort.
I agree with this. In our case, we were able to install a more efficient AC unit (16 seer) because we upgraded the furnace to a two stage blower. There was a further efficiency gained in that the blower was D.C. powered vs. the old furnace which was AC powered. Finally, the new furnace is much quieter than the old furnace and there is a noticeable increase in the comfort and consistency of temperatures in different rooms.

Rough estimate, I'd say my utility bills dropped $30-50 a month on average with the new system although some of that is probably due to slightly declining energy costs.

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by Abe » Sat Jul 22, 2017 11:53 am

I have rental properties, and I usually replace both, the A/C and furnace at the same time, especially if it is as old as yours. My cost for replacing both typically runs around $4,000 but of course depends on the unit size. You need to shop around.
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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by squirm » Sat Jul 22, 2017 1:35 pm

They're over 20 years old! Just replace them both and move on.

URSnshn
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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by URSnshn » Sat Jul 22, 2017 3:11 pm

I appreciate all the suggestions, comments and advice! I'll be re-reading these posts, getting some estimates and doing a bit of research before I make my decision. Thank you - I have a lot more to go on now!

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by Abe » Sat Jul 22, 2017 3:25 pm

If you know anyone who owns rental property, you might ask them who they use for HVAC work. They usually know the ones who are trustworthy and will give you a reasonable price.
Slow and steady wins the race.

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by Watty » Sat Jul 22, 2017 3:58 pm

URSnshn wrote:I appreciate all the suggestions, comments and advice! I'll be re-reading these posts, getting some estimates and doing a bit of research before I make my decision. Thank you - I have a lot more to go on now!

I have found that September is a really good time to get HVAC quotes since it is between the cooling and heating season(at least where I lived) so they have very little other work to do so they are looking for any work that they can get.

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by mbres60 » Sat Jul 22, 2017 4:02 pm

Same thing happened to us last summer. Freon leak in a/c. They put more in. It last about 3 or 4 days. Was told it was not worth putting more in. Our system was 19 years old. We were told to replace both furnace and a/c so we went and got three quotes and had it replaced.

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by Jim180 » Sat Jul 22, 2017 4:31 pm

I agree with those who say get both furnace and A/C now. I assume you still have the original heat exchanger in the furnace so I think the average lifespan on the heat exchangers is around 20 years. Also, if you wait for the furnace you will end up paying the installer labor to remove and install the A/C coil twice. My A/C coil is mounted below my furnace and it took a technician 2-3 hours to replace it when it leaked. Perhaps a top mounted A/C coil can be replaced a bit faster but it would still take some time. I wouldn't pay them to do it twice.

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by Fletch » Sat Jul 22, 2017 6:37 pm

Jim180 wrote:I agree with those who say get both furnace and A/C now. I assume you still have the original heat exchanger in the furnace so I think the average lifespan on the heat exchangers is around 20 years. Also, if you wait for the furnace you will end up paying the installer labor to remove and install the A/C coil twice. My A/C coil is mounted below my furnace and it took a technician 2-3 hours to replace it when it leaked. Perhaps a top mounted A/C coil can be replaced a bit faster but it would still take some time. I wouldn't pay them to do it twice.
+1 The advances in AC/furnace technology in the past 20 years is huge. ECM variable speed motors on the air handler, scroll compressors, smart thermostats, multi-stage furnaces, better filters (if you have allergies) etc. The downside is the new systems will last only 10+ years vs. the old systems that used R22 and were very energy inefficiant lasted 20+. All in all, I'll take the new systems for the greatly increased comfort they provide.
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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by tooluser » Sat Jul 22, 2017 7:17 pm

At 21 years old I would replace both units, same as with washer/dryer or kitchen appliances (though those don't tend to come in pairs). You've gotten value from them.

However, if I personally did not use the AC I would probably skip it and not worry about resale.

Additional items to consider:
- If you have asbestos on your furnace ducting it is a good time to have it removed.
- If you would like to replace or upgrade your ducting it could lead to increased efficiency, especially if there are leaks.
- New ducting also implies the potential for addition of ventilation to parts of the house that need more. Do you have dead spots?
- If you would like to relocate the furnace (e.g. from a closet to the attic), that can also be done.

I did all of the above when my 53 year old furnace finally kicked it, and am very happy several years later, knowing that it is all good.
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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by lazydavid » Sun Jul 23, 2017 6:58 am

jharkin wrote:#4 A new system will be more efficient but the gains now are into diminishing returns. My MIL has a 90s vintage gas furnace in her condo and it's 96% AFUE. A 2017 system might be 98% AFUE. Do the math on ROI spending $7000 to save $5 a month on the gas... :oops:
Efficiency drops with age. So a 20-year old unit that was 96% when new, might only be in the high 70s or low 80s now.

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by sco » Sun Jul 23, 2017 8:58 am

I'd do both, ask what installing each separately would cost... likely most of the savings is labor doing them both at the same time..

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by bertilak » Sun Jul 23, 2017 10:26 am

squirm wrote:They're over 20 years old! Just replace them both and move on.
+1

I just replaced my 10yr-old AC less than a month ago. To get all the modern advantages we had to also replace the integrated gas furnace. I got 3yr 0% financing. (My next Credit score will take a hit.) I had to do something because it simply stopped working in 90-100 degree weather. It was out of Freon which costs a fortune to replace plus the unknown expense of finding and fixing any leaks. The 20yr-old will certainly have Freon.

Things have come a long way in the AC world in 10-20 years! 20 years old is ancient.

There are major improvements in efficiency AND comfort. We had a mold problem and had to turn the old AC down (colder) to get rid of the moisture. The new two-stage system is much better at dehumidifying so we don't need to run it as cold. In addition to saving money, comfort is up because it keeps the house at a more reasonable and constant temperature and humidity. The thermostat has a "keep-below" humidity setting. I forgot how much rumbling noise the old one made and whenever it started up there was a loud, startling, noise. Now it is nearly silent, both when starting and running.

The replacement is a Carrier Infinity system. I hope it proves reliable and lives up to its 10yr/2yr parts/labor warranty.
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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by limeyx » Sun Jul 23, 2017 6:55 pm

BIGal wrote:I would get a couple of more quotes and also discuss with friends/family in the area for recommendations on who they have used. 7.5 to 8k seems quite high....but then again, I don't have the details (nor want them) but you really need to "shop around" with that kind of estimate. Replacing a 21 YO system is probably a good idea for efficiency too...it should result in lower utility bills. You may want to call your utility for their input...quite often they offer rebates that could be substantial. Good Luck.
Yeah I'd definitely get a quote from a company who's labor rate is < $250/hr !

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by Alto Astral » Sun Jul 23, 2017 9:47 pm

URSnshn wrote:Surprisingly, I didn't realize the air conditioning wasn't working - I've been comfortable without it. I could simply have it removed, but I wonder about resale value without it.
I am in a similar boat. Got a 20+ year old AC. Have had to put in $100 worth of R22 freon a few years in a row. I don't use it much in the midwest and have ceiling fans that are sufficient during the night. Since I don't use it much I'm just waiting for it to stop working before I get a new one. Won't be an emergency if it does stop; the house does not get too hot. 20 year old furnace is just fine. I do annual maintenance on both. For resale, I'd just offer a home warranty for a year (which is what I got during the purchase)

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by CurlyDave » Mon Jul 24, 2017 2:02 am

I would definitely replace both units. The heat never fails in July, and the AC never fails in December. But, I would get quotes on a few other brands. You may well see a remarkable difference.

If you are handy, Goodman is one of the few major manufacturers who will sell a unit directly to a consumer. We have 20-30 year old rentals and I usually replace whatever is in there with a Goodman unit. But, I can do the work myself and have enough rentals that I employ (as in 40 hours/week salary and vacations) a full-time maintenance guy who is very good. Goodman is usually considered one of the lower-end manufacturers, but I have had very satisfactory results with their units. We routinely repair HVAC units and the motors and electrical controls are typically the same among all of our units, no matter which manufacturer put their name on the whole assembly.

You should be aware that a DIY installation means that Goodman will not warrant the unit at all. I have only had one problem with a new unit, where the factory pinched a wire between two components, shorting it out. We just replaced the wire for less than $5 in materials.

A couple of years ago, the last one I replaced was ~ $1800 for a packaged gas heat/AC unit large enough for a 1000 sq. foot rental. $3k would get you one big enough for a 2000 + sq foot house.

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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by 2comma » Mon Jul 24, 2017 10:58 pm

Funny you mentioned Goodman. When we did an addition I decided it was a good time to upgrade the AC and furnace. I negotiated on price only so of course he installed the least expensive unit he could find. No one I knew that I asked about brands and installers were any help while I was deciding but a week after I had it installed someone I respect said oh you should have got a Trane - only one that makes their own compressors, the quietest... So I figured I goofed. Then we had a capacitor go out, common repair item in all units and the repair guy said he didn't have any issue with Goodman, he had one in his house. Hum? I've recently started trying to educate myself about HVAC maintenance and repair and started watching a lot of youtube videos (I'm proud to say I can now replace a bad capacitor or contactor myself, not so much because of the money but the availability of getting someone here to replace them quick in the very hot and humid south). These videos are usually made by the small independent guys and they have their opinions! They mostly joke about the Trane AC's they fix "nothing stops a trane", yeah right. They are the same Copeland scroll compressors as all the others. The only definitive thing I heard one say was Trane put over temp/pressure sensors in to protect the compressor. One said Goodman doesn't to save money, was probably a good idea but the tech can add them for cheap. The other thing the small guys don't like is they are required to buy a minimum $ amount of Trane per year, they have sales zones to restrict competition and the Trane salesmen are good at their jobs, perhaps a little too good. I've heard a good install is more important than the actual brand and the more I learn the more I understand why they say that.

I'm with most of the others, you got 21 years out of the HVAC it doesn't owe you anything. The thing that bothers me about oldish furnaces is the heat exchangers are subjected to a lot of heat/cooling cycles and the exchanger metal is not that reassuringly thick. They can and do eventually get cracks or holes from fatigue, rust or burn thru and then the carbon monoxide gets blown right into the home. The last gas furnace I had replaced had three cracks in it. I'm not aware of what current safety thoughts or codes are on carbon monoxide detection but I think having a good CO detector in the house is a good idea, more so with an old furnace. Dying in your sleep ain't a bad way to go but I don't want it to happen prematurely.

Edit: I see new building codes require CO detectors as of July 1, 2008 within 10 feet of all sleeping areas if you have a fossil-fuel-heater or appliance, a fireplace or an attached garage.
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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by itstoomuch » Tue Jul 25, 2017 1:35 am

We replaced the gas because the tubes were shot.
Installed a Coleman HF gas.
Kept the Heat pump, now about 40 years old. Replaced couple of motors, capacitors, relays?
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Re: Am I getting good advice - replace the AC, not the 21 year old furnace

Post by jharkin » Tue Jul 25, 2017 11:34 am

lazydavid wrote:
jharkin wrote:#4 A new system will be more efficient but the gains now are into diminishing returns. My MIL has a 90s vintage gas furnace in her condo and it's 96% AFUE. A 2017 system might be 98% AFUE. Do the math on ROI spending $7000 to save $5 a month on the gas... :oops:
Efficiency drops with age. So a 20-year old unit that was 96% when new, might only be in the high 70s or low 80s now.
Why? A gas furnace is a very simple device - a burner, an air/flue gas heat exchanger and a blower. Unless there is a clogged filter or the heat exchanger rusted though there is not really anything in a gas fired furnace that could cause efficiency drop with age.

A hot water system clogged with rust and lime scale, or an oil fired unit that has not been cleaned /adjusted periodically is another story... but I dont believe we are discussing hydronics or oil fired heat here.

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