# Replace Heat Exchanger or Furnace



## deccher

I have just been told I have a bad heat exchanger in my GMP125-4 (Janitrol, but now Goodman). I was told $400 to $600 for exchanger, and $1,100 labor. I asked how long it takes and he said 5 or 6 hours. They must think a lot of themselves, demanding over $180 for the work. I found the part on-line for just under $300, and apparently most HVAC work can be done for around $85 per hour. I am planning to get several other estimates. Point being, I am looking at a minimum of 5 hours at $85/hr + $300 for heat exchanger = $725. More realistically I will get estimates for $800 to $1,000 total, I am guessing.

The same HVAC company did their free sizing on my house and figured I need a 115 BTU furnace with a 5 ton blower (house is finished basement + 2 story, total SF of 3,250). He recommended the 95% efficiency Goodman GMV-95-115. He was offering the "one time only price" of $5,892 installed.

Given my yearly averaged gas bill is $103/mo, including my water heater, a 15% efficiency gain would take forever to pay for the new furnace. If I save roughly 15% on my bill (going from 80% to 95% efficiency), and assume the whole $103 is the furnace, I save a grand total of $180/yr.

It seems a no brainer to me to fix my existing furnace for around $1,000. Does anyone have any thoughts that contradict my thinking?

Could I get a new furnace from another contractor for substantially less than these guys are quoting? I am thinking the labor must be really high to put in this furnace, given I found the exact model on the Internet for just under $1,600. See http://www.acwholesalers.com/Goodman-gas-furnaces-lp-natural-gas-furnace-p/11140.htm

Thank you for taking the time to read this and reply.


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## beenthere

As contractors. We charge what we need to stay in business, and to of course pay employees.

So, many of us are well over 85 bucks an hour.

Get some other estimates.
A one time price offer, is a good sign to call some one else.

Since your GMP seems to be over 20 years old.
Get quotes on other brands also.

A 95% may only work out as a 15% savings on paper.
But, most come out saving more then that(and yes, some less).

A new unit will come with at leat a 20 year HX warranty, and a 5 years parts warranty on the other furnace parts.

10 years from now, is your gas going to cost the same as it does today?


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## Home Air Direct

+1 for everything BEENTHERE offered:thumbsup:

If you do decide to go with a new furnace, you may consider going with a standard blower motor 93% efficient setup instead of the Variable Speed. There is usually a considerable price difference between the VS product and the standard. Your current furnace is standard and if that has served you well in relation to comfort, then you should be fine. I am often suspect when contractor want to put VS units in older homes. 

On the subject of replacing the heat exchanger. I am an HVAC contractor, so I am all about new equipment, but different folks have different philosophies about repair versus replacement. Since you already have a very reasonably low gas bill, your decision should probably be based on your immediate and available finances. Every time one of my adult children complains to me that they are going to have to repair their car and the cost will be $500, they will try to rationalize a new car by thinking it would be better to apply that $500 in payments. I always respond by reminding them that they only have to drive the car for 1 1/2 months to justify the $500 repair.

If you do buy the heat exchanger online, you may want to offer the contractor of your choice an incentive since he will be unable to profit from the parts sale. If the going rate for his work is $85 an hour, maybe an offer to pay $100 an hour for his services would not be unreasonable. The total cost to you would be at max. An additional $75. The reality is this repair should only take 3 to 4 hours.

I often see homeowners beat up by contractors when these types of questions are asked. The reality is, it is your money and you should decide how when and where you spend it. You also are responsible for the outcome of your decisions.

Good luck to you.


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## jogr

Call Goodman with the model # and serial #and see if your heat exchanger is under warranty. Mine was so I didn't have to pay for the part. However I did have to pay for the labor. If your heat exhanger is still under warranty (Goodman is lifetime) your contractor might not realize it so you might actually have to tell them (I had to tell mine).

Most HVAC companies would rather sell you a new furnace so you might need to call a few to find the best install price. But make sure you go with a reputable company - a low price isn't any good if it's done wrong.

You might not actually be able to buy a heat exchanger online unless you are a licensed HVAC contractor. I couldn't find anyplace online that would sell me the heat exchanger instead of a licensed contractor. Goodman would only allow a licensed HVAC dealer to receive the replacement exchanger under their warranty. If you do end up finding one you may find that local HVAC contractors won't want to touch it since they have no control over what you are giving them to install.

I ended up paying $650 labor for mine but I'm in a somewhat rural midwest area where cost of living is fairly low. The $1100 estimate might be very reasonable for your area. It really does cost a lot to run a business - much more than just paying an employee his hourly wage while he's at a customers house.

You want to make sure you replace a bad exchanger right away cause they can be deadly and make sure you have good carbon monoxide detectors.

Good luck


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## beenthere

I'm pretty sure, GMP HX's are only 20 year limited warranties.


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## SKIP4661

What is the serial number? If its under warranty Goodman has a program where your furnace can be replaced with a newly designed furnace for about what you were quoted for labor for htx.


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## deccher

Thank you all very much for your responses. Your advice is appreciated.

So much has happened in the past three days, but I want to share it for the sake of others. I’d also appreciate your recommendation on my course of action.

My house was built in 1998 with the Janitrol / Goodman GMP125-4. With some checking, the furnace was actually manufactured in 1993. Furnace S/N is 9702854654.

I called an HVAC Contractor on Wed evening. He came out and assessed my furnace as follows "Found 4 big cracks on the heat exchanger, 1" to 2" in size coming off eyelets letting bi-products into air stream. Very unsafe to run." This is written on my receipt, and he basically told me the same thing. He then pitched me furnaces, with the "premium level" 95% Goodman 2-stage, variable speed coming in at $6,700 installed. I believe the 80% much like my current one, but with variable speed blower was quoted around $4,000. These are installed prices with any applicable duct/venting work.

I then user QualitySmith.com to set up 3 appointments for the following day, and set up one through Home Depot's services group. NOTE: Quality Smith set up the appointments only 1 hour apart, you really need a minimum of 2 hours to get new furnaces sized and quoted. Needless to say, my house looked like that Lone Tree commercial with all those lenders standing around to make their offer. Rude, but also a little commical. I told them to let QualitySmith know what happened.

Anyhow... The first contractor started to put together a quote, and I mentioned I would feel a lot better if I had a second opinion on the heat exchanger really being bad. They brought out a tech who used a CO sniffer to sniff the output air (small hold in duct right above furnace) and several heat registers. No CO measured (gauge starts measuring at 1 ppm). I asked them to go ahead and quote me an 80% and 90% plus furnace, just in case, but informed them I understood if they were unwilling, given I could be wasting their time if no replacement was needed. They complied and quoted me:
80% -- Comfortmaker VS 80 (C8MPV125J20C) variable speed 2-stage furnace with a non-programmable 2 stage thermostat for $2,000 installed (parts, labor, and tax).
90%+ (as they show on quote) -- Comfortmaker VS 90 (CPMPV125L20D) variable speed 2-stage furnace with a non-programmable 2 stage thermostat for $2,495 installed (parts, labor, and tax).

Second HVAC Contractor (installed prices):
80% Carrier $3,982
80% Payne $3,207
95% Carrier $5,357
90% Payne $3,653
Above prices include the 10% off for signing before midnight that night, and 5% for cash. They also told me I don't need a new thermostat with a 2-stage variable speed furnace, which from what I have researched sounds wrong.

Third HVAC Contractor (installed prices)
80% American Standard 80 Comfort R Variable Stage with digital programmable 2-stage thermostat $3,200
95% American Standard 95 Comfort R Variable Stage with digital programmable 2-stage thermostat $4,800

Fourth HVAC Contractor (installed prices)
95% Trane XV-95 100,000 BTU 2-Stage w/Variable speed blower, programmable thermostat $3,860. 
He pulled out documentation on the XCel Energy rebate of $120 and the 2009 tax credit of $150 and told me they will fill out the XCel rebate and send it in for me.

Finally, with all of that done, I was still concerned about whether or not I really had cracks in the heat exchanger, since there were no measurable CO emissions per the first contractor. I decided I had to call someone with no interest in selling me a furnace. I called Xcel Energy's Emergency line and they said CO is an emergency, so they sent out a tech at no charge. This gentleman was in his 50s with years of experience, and confirmed that he knows of cases where such a "selling process" had been done with no heat exchanger issue. He took his sniffer and measured at the output of the furnace (above it, just above the AC condenser) in the duct work (a hole he stuck it through), sniffed all through the furnace while running, around all the lines, etc. and then went to about 1/2 the registers in the house and several cold air returns with no presence of CO. He then went back and sniffed all around the water heater, still a reading of zero. I asked if his measurement tool was working. We then turned on the hot water so the water heater would light, and while he had the little pilot light door open with sniffer inserted, both the natural gas and CO levels went up for about 20 seconds, then fell back to zero. So, the sniffer was working, and no apparent problem with the furnace. He said that is how he would report it, but did say that there could be small cracks in the heat exchange which are not measurable from CO emissions.

Last night I read consumer reports on-line and went and bought 3 Kindle CO detectors with displays to show CO ppm measured, with a peak feature that shows highest level ever measured for the life of the device. I put one right outside the furnace door in the basement (the furnace in unfinished portion, the detector in the finished portion), one in my family room on the main floor, and one in the upstairs hallway where all the bedrooms are. None of them have come off zero on the display. I turned the furnace back on yesterday at 3 pm.

I got a call from the first contractor last night asking if I had made a decision. I expressed to the lady that I thought I was being scammed, and told her the whole story. They sent out a senior technician this morning to show me the cracks, and said if he could not, they would pay me $300 and terminate the technician. He removed the blower, then came to get me, and had me look up inside with a mirror and flashlight, and showed me what I would call very small cracks. He told me he would pull the heat exchanger so I could see them better. He took apart the furnace and called me back down 30 minutes later. Sure enough, we found not just 4 cracks, but 7. Some were 1/4" long, the longest maybe 1-1/2". I could not see that any of them would allow air to flow through them, but nonetheless there were cracks. They were not lying, but the technician had told me verbally that he measured CO at 35 ppm before he looked at the cracks, which nobody else could duplicate. He put the furnace back together in another 30 minutes. He made a call and said they could get the heat exchanger free because it was still on warranty, and put it in for $850 in labor now, rather than the $1,100 originally quoted. So, it appears their hourly rate is $425 an hour giving them the benefit of the doubt that putting a new one in rather than putting the old one back in might take twice as long.

So, apparently I have a cracked heat exchanger with no measurable CO emissions and my furnace is running as I type.

Based on the fact that I have $5,000 in my savings account and no credit cards, what would you do knowing what I know?

If you want to see pictures of the cracks, let me know. The picture files are 3 MB jpg files from my 8 mega pixel camera, so posting them in this forum is probably not the best option, but I would be happy to Email them to you.

Thanks again to all of you for your feedback.

Dan


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## hvaclover

http://www.dnmech.com/lit/Good_GMP_SS186ce.pdf


it's an 80%er, only 20 year warranty on ex. Time for a new one


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## JohnH1

I also recomend new. The Goodman GMP units in my opinion had flaws in the design of the heat exchanger causing the rings to pop off. New will give more dependiable service than a older unit.
Rember proper installation is more important than the brand of equipment. I love the VS equipment. Costs more but well worth it in my opinion.


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## hvaclover

JohnH1 said:


> I also recomend new. The Goodman GMP units in my opinion had flaws in the design of the heat exchanger causing the rings to pop off. New will give more dependiable service than a older unit.
> Rember proper installation is more important than the brand of equipment. I love the VS equipment. Costs more but well worth it in my opinion.



Jesus Christ could have installed that model and it would have still died.

Just a bad design...


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## yuri

Apparently the new units are quite nice now that they brought them up to the Amana vs Goodman standards.


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## hvaclover

I agree. I am seeing my Amana guy this coming Tues.


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## SKIP4661

According to that serial# that furnace is a 1997 model. I would suggest contacting a goodman distributor, such as Johnstone Supply, to discuss the warranty options. There are options that shouldn't cost you your first born child.


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## Home Air Direct

I am going to open up my closet a little and let you know a little something about my past. I was the Vice President of a midsized wholesale distribution company who distributed Goodman/Amana throughout the state Illinois, before creating my own business.

I have very vivid memories (that felt like nightmares) of replacing over 200 GMP model Goodman furnaces between 2005 - 2007. Goodman took care of most of them, but the paperwork was a living nightmare.

Goodman changed their heat exchanger to tubes after the clamshell/rivet fiasco. They have been relatively trouble free since.

The current Goodman furnace is a decent box. Do not get all caught up in the crazy warranties that they offer up. It is an actuarial numbers game that they are playing. I will not go into to it here, but I have sat in meetings in Houston at Goodman corporate and have had to pick up my chin from the plans that Goodman has for dominating the market.

As far as which furnace to choose? There is really no bad product on the market today. The reality is that a bad install will kill a great furnace.


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## hvaclover

hvaclover said:


> http://www.dnmech.com/lit/Good_GMP_SS186ce.pdf
> 
> 
> it's an 80%er, only 20 year warranty on ex. Time for a new one



Dhu...missed by ten years. Is still under warranty but i would still opt for a new one.


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## hvaclover

Home Air Direct said:


> I am going to open up my closet a little and let you know a little something about my past. I was the Vice President of a midsized wholesale distribution company who distributed Goodman/Amana throughout the state Illinois, before creating my own business.
> 
> *I have very vivid memories (that felt like nightmares) of replacing over 200 GMP model Goodman furnaces between 2005 - 2007. Goodman took care of most of them, but the paperwork was a living nightmare.
> *
> Goodman changed their heat exchanger to tubes after the clamshell/rivet fiasco. They have been relatively trouble free since.
> 
> The current Goodman furnace is a decent box. Do not get all caught up in the crazy warranties that they offer up. It is an actuarial numbers game that they are playing. I will not go into to it here, but I have sat in meetings in Houston at Goodman corporate and have had to pick up my chin from the plans that Goodman has for dominating the market.
> 
> As far as which furnace to choose? There is really no bad product on the market today. The reality is that a bad install will kill a great furnace.



Heck, guy. You ain't telling us nothing we didn't already know.

I felt sorry for my guy at Flo Co who had all that paper work to do after the return EX.


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## Home Air Direct

hvaclover said:


> Dhu...missed by ten years. Is still under warranty but i would still opt for a new one.


Yeah, I missed that too. I should have known better.

But, the Op should take the fact that the servicing contractor who found the crack and then pushed the replacement over the repair with the Goodman brand was not their to help, or they would have offered up the warranty work in order to gain confidence and a probable furnace replacement when the time was right.


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## hvaclover

Home Air Direct said:


> Yeah, I missed that too. I should have known better.
> 
> But, the Op should take the fact that the servicing contractor who found the crack and then pushed the replacement over the repair with the Goodman brand was not their to help, _*or they would have offered up the warranty work in order to gain confidence and a probable furnace replacement when the time was right.*_



Damn straight. Unless the HO is sandbagging that one little fact.

you know how it goes with a complaint against an aggressive production oriented work force.


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## suthrnreject

*Such a thing as dirty heat exchanger?*

My American Standard furnace (13-14 years old) has been acting up lately, not wanting to start for a while, especially in the mornings. It can take around 5 minute to finally get started, but once started, runs just fine.

We thought this was a thermostat issue, but after one conctractor spent two hours in the basement checking things out, he said the pressure reading was low, which was causing it to cut out early or take a while to start up. He attributed this to a dirty heat exchanger (i.e., the caked on dirt was causing a blockage and thus bad pressure readings), which he could clean for only $1000!!!!. However, if this turned out not to be the source of the problem, then I would need to replace the furnace for the low, low price of only $6000. This just didn't seem right to me.

I called another contractor this morning, and he felt it was the pressure switch itself if it was indeed not reading properly, or something to do with the blower. He never heard of cleaning the heat exchanger, although he said he could probably do it by simply vacuuming out the soot if that's what I wanted. The other guy made it sound like it was more than soot caking the exchanger, like it was hard stuff that would need to be scraped off (I have no idea what this would be).

Absent a dirty exchanger, it might be due to cracks in the exchanger causing pressure problems.

In any event, should I first try to get the exchanger cleaned (by the second contractor, and not for $1000), and if that does't work, and if it's not the pressure switch, can I simply replace the heat exchanger rather than purchase a new furnace? I can't afford a new furnace right now, or even a $1000 cleaning.

Something about the first guy, even though he spent two hours of his time and didn't charge me for it, still doesn't sound right. He did lower the price of the cleaning to $875, and then said that if it turned out not to be the problem, and I bought a new furnace, they would only charge me $125 for the cleaning, and apply the remaining cost to the new furnace.

Is this a scam?

Any and all help and suggestions are appreciated.


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## hvaclover

A sooted exchange is more times than not caused by a cracked heat exchanger. Most companies are not going to take a chance cause it does turn out to be a bad exchange.

If you are not comfortable with the cost get other estimates.But if you can't afford it, the diff in price from company to company won't be enough to make a diff for your problem.


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## Dr Heat

Given my yearly averaged gas bill is $103/mo, including my water heater, a 15% efficiency gain would take forever to pay for the new furnace. If I save roughly 15% on my bill (going from 80% to 95% efficiency), and assume the whole $103 is the furnace, I save a grand total of $180/yr.

It seems a no brainer to me to fix my existing furnace for around $1,000. Does anyone have any thoughts that contradict my thinking?

Could I get a new furnace from another contractor for substantially less than these guys are quoting? I am thinking the labor must be really high to put in this furnace, given I found the exact model on the Internet for just under $1,600. See http://www.acwholesalers.com/Goodman-gas-furnaces-lp-natural-gas-furnace-p/11140.htm

Thank you for taking the time to read this and reply.[/quote]
1 to determine your savings take your gas bill average for a month This is not perfect but close enough for your purpose.
2 subtract 20% this is because you can only get 80% of the energy out of natural gas by burning it
3 now you need to take your average bill for the summer and subtract that. this is to take into account fuel used for dryer water heater and stove (if you have a pool heater this will not work) it will also take out fixed costs Like delivery fee (propane) 

Once you have subtracted these non heating fuel costs you simply take 15% if that is the efficiency difference and wella you approximate savings.

I have not found a case where the payback in my area warrants the 90 over the 80
Bare in mind we need to consider interest you will pay on financing or interest lost by withdrawing savings.

Consider how long you expect to stay in your home.


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## Dr Heat

one more thing if the furnace is past warranty replace it if it is still in warranty replace the heat exchanger


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## rtbrps3383

As someone who is not in the business, and who is dealing with questionable contractors, I must have missed something in this thread. I hope maybe you can explain to me.
As I understand it, this guys furnace runs, and still runs okay. I don't believe that it was stated why the contractor was at the house in the first place. Seems to me, that the only thing wrong, is that the exchanger has a few small cracks in it. They aren't leaking CO, so there is no danger posed. 
So why do anything? 
He has a CO detector - so if the exchanger does fail, he will know. 
If your concerned about the exchanger failing, why can't it be fixed?
Seems like it would be a much less expensive repair than a replacement.
Thanks for your replies.


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## beenthere

Heat exchangers can't be fixed.
They are made too thin to weld, or patch.

As for CO detectors, they don't protect you. By the time they alarm you, you are already feeling the effects of the CO.
The reason they are set so high, and take so long to go into alrm, is vecoause of all the false alarms fire companies were getting.

Neither you, nor him know if there is CO in his air stream.
Because no one used a sensitive enough CO meter, to check.


Read the rating on your CO detector if you have one.
They are a false sense of security.


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## Dr Heat

beenthere said:


> Heat exchangers can't be fixed.
> They are made too thin to weld, or patch.
> 
> As for CO detectors, they don't protect you. By the time they alarm you, you are already feeling the effects of the CO.
> The reason they are set so high, and take so long to go into alrm, is vecoause of all the false alarms fire companies were getting.
> 
> Neither you, nor him know if there is CO in his air stream.
> Because no one used a sensitive enough CO meter, to check.
> 
> 
> Read the rating on your CO detector if you have one.
> They are a false sense of security.


Been is absolutely correct cracked heat exchangers cannot be fixed. 

Now there are several things that techs call cracks for example popped rings these can be fixed. You buy the comprehension fitting from the manufacturer (not all offer them) and insert it then presto (you should also increase you liability ins. and pray often pray without ceasing) 

Really if it is under warranty replace the HE if it is not buy a furnace do not expose your self or your loved ones to even low levels of CO, the long term neurological damage is foreseeable and therefore preventable.

For this reason I hate Co detectors People tell me ya the co detector only goes off a couple times a day so I figured maybe next fall Il get the furnace checked.:wallbash: People this is your life.


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## terrylyn11

deccher said:


> I have just been told I have a bad heat exchanger in my GMP125-4 (Janitrol, but now Goodman). I was told $400 to $600 for exchanger, and $1,100 labor. I asked how long it takes and he said 5 or 6 hours. They must think a lot of themselves, demanding over $180 for the work. I found the part on-line for just under $300, and apparently most HVAC work can be done for around $85 per hour. I am planning to get several other estimates. Point being, I am looking at a minimum of 5 hours at $85/hr + $300 for heat exchanger = $725. More realistically I will get estimates for $800 to $1,000 total, I am guessing.
> 
> The same HVAC company did their free sizing on my house and figured I need a 115 BTU furnace with a 5 ton blower (house is finished basement + 2 story, total SF of 3,250). He recommended the 95% efficiency Goodman GMV-95-115. He was offering the "one time only price" of $5,892 installed.
> 
> Given my yearly averaged gas bill is $103/mo, including my water heater, a 15% efficiency gain would take forever to pay for the new furnace. If I save roughly 15% on my bill (going from 80% to 95% efficiency), and assume the whole $103 is the furnace, I save a grand total of $180/yr.
> 
> It seems a no brainer to me to fix my existing furnace for around $1,000. Does anyone have any thoughts that contradict my thinking?
> 
> Could I get a new furnace from another contractor for substantially less than these guys are quoting? I am thinking the labor must be really high to put in this furnace, given I found the exact model on the Internet for just under $1,600. See http://www.acwholesalers.com/Goodman-gas-furnaces-lp-natural-gas-furnace-p/11140.htm
> 
> Thank you for taking the time to read this and reply.


hello, my furnace keeps shutting off, when we press the reset button it runs for about 5 minutes then shuts back off again. did you have the same problem. we are trying to find out if our heat exchanger is bad. thanks


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## yuri

Which reset button are you pressing, post a pic of it. The heat exchanger may be cracked and needs to be inspected by a Pro. Goodman had a lot of problems with them.


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## COLDIRON

Replace it you already have a quote to install the HE under warranty it will cost anywhere from 850 to 1K why put that into it?

Go with the quotes you have for 2K and 2.5K for the new system, it's worth it. The money it cost to install the HE will pay for half the new one.


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## coolingrepair

what is the serial number on that furnace, it would have had a 20 year warranty on the heat exchanger


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## hvac122

I can't believe that you have seven cracks in you heat exchanger and are still running the unit. You must not value your families lives very much. Those cracks open and close with expansion and contraction and could open wide anytime. If the service company left it running after seeing this then bad on them. 

As said a co detector is not the way to check a heat exchanger. One installed in your house like, the ones you bought, as said do not alarm soon enough or at all. Read the fine print on them. Most don't alarm until 35-40 ppm is sensed and then they have to have that reading for hours before they alarm. You could have 30 ppm for example in your house and it would never alarm. Do you know how sick or dead 30-40 ppm can make you or your kids? Wow. The service company that you hired tries to save your life and all you can do is find things wrong with them. Sorry but I will not throw them under the bus and think they did the right thing bidding a new unit and not wanting to repair the junk you have.

Sorry if this is harsh but I get tired of people putting us down when we are just the barrer of bad news. We did not make the problem only diagnosised it. 

Also you have no idea how much it takes to stay in business and shouldnt try to set others rates.

I am sure you will go with the cheapest option and company so don't complain later with what you get.:whistling2:


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## hvaclover

Home Air Direct said:


> I
> As far as which furnace to choose? There is really no bad product on the market today. The reality is that a bad install will kill a great furnace.


 You got that right...no truer words spoken. But furnaces are like any machine some are better made than others.


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## hvac292

the tires on my car are bald and the steel is showing but they still have air in them. I guess its still safe to drive. seriously.. no matter how big or how small a crack in a heat exchanger is its going to end up doing the same thing... leaking. The prices you stated are average. Stop playing around and be responsible. Replace the furnace.


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## HVAC/R Instr.

*pressure difference*

Visibly cracked heat exchanger, but no measurable CO levels. Here is a possible explanation. 

This furnace appears to have an inducer fan, which draws combustion gases through the exchanger and puts the inside of the exchanger under a negative pressure. Typically these furnaces have the indoor blower upstream of the exchanger, which means the indoor air & heat exchanger exterior are under positive pressure. Both of these factors contribute to safety and a positive pressure differential between indoor air and combustion gases. In theory, any cracks or leaks will cause indoor air to leak into the heat exchanger rather than combustion products to leak to the indoor air stream. However, it may be possible these cracks can leak the wrong way, perhaps at startup when the burner can be on for a short time, but the indoor blower has not come on yet.

If cracked, I feel the exchanger or furnace should be replaced regardless of inherent safety. If it is 15-20 years old, I would recommend new. Other components will begin to fail and be costly. Glad to see you recognize there may be a long payback for higher efficiency models.


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## Technow

Two year old post......the OP is either dead or took the advice.......:jester:


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## REP

A couple of things hat I wonder about.
The first is this heat excghanger has not failed by poping the rings as many do,so I wonder why this exchanger failed.Could there be design problems with the duct??Could the gas pressure be too high coming from the gas valve??So what caused the cracks??
Now little cracks always turn into big cracks and they do this over time and they do this at night a lot because it gets colder at night and the furnace gets hotter the longer its on.If it has small cracks you should just be greatfull you knowe about it and can do something now before you or anybody in the house gets sick.
I noticed that there was a range of furnace sizes in your post.Each house has a size needed.What size does your house need??Now is the time to find out.
Any competant contractor can do a manual "J" AND a Manual "D" to zero in on the size and design of the ductwork needed for your house.
Figure it this way ; your money is valueable to the contractor.He needs your work to feed his family.Now if he is too lazy to do the manual "J" and the manual"D" and he is using short cuts to quote you,then what makes you think he won't take short cuts in installing your job?? 
Any mistakes made now will only cost you later on.Instead of just getting something done,Get it done right.


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## Docrings

beenthere said:


> As contractors. We charge what we need to stay in business, and to of course pay employees.
> 
> So, many of us are well over 85 bucks an hour.
> 
> Get some other estimates.
> A one time price offer, is a good sign to call some one else.
> 
> Since your GMP seems to be over 20 years old.
> Get quotes on other brands also.
> 
> A 95% may only work out as a 15% savings on paper.
> But, most come out saving more then that(and yes, some less).
> 
> A new unit will come with at leat a 20 year HX warranty, and a 5 years parts warranty on the other furnace parts.
> 
> 10 years from now, is your gas going to cost the same as it does today?


YES... as the price of gas will actually be less than when this post was written. The supplies of NG are enormous, and will be a much better deal per BTU than electricity.


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## Mr.HVAC

Technow said:


> Two year old post......the OP is either dead or took the advice.......:jester:


LOL, I was going to reply but then noticed the date. I guest you are right, the OP is either dead or took the advice. Let see if someone else reply

ROFL


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## poppyo

90 percent plus is the only way to go.You Will be paid back in $$$$$$$$$$$$$$$$$ savings in no time at all


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## poppyo

Replace the old 80 percenter.......................................................


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## poppyo

Get er done for about 4 Grand.............Fair Enough......................


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## plummen

jogr said:


> Call Goodman with the model # and serial #and see if your heat exchanger is under warranty. Mine was so I didn't have to pay for the part. However I did have to pay for the labor. If your heat exhanger is still under warranty (Goodman is lifetime) your contractor might not realize it so you might actually have to tell them (I had to tell mine).
> 
> Most HVAC companies would rather sell you a new furnace so you might need to call a few to find the best install price. But make sure you go with a reputable company - a low price isn't any good if it's done wrong.
> 
> You might not actually be able to buy a heat exchanger online unless you are a licensed HVAC contractor. I couldn't find anyplace online that would sell me the heat exchanger instead of a licensed contractor. Goodman would only allow a licensed HVAC dealer to receive the replacement exchanger under their warranty. If you do end up finding one you may find that local HVAC contractors won't want to touch it since they have no control over what you are giving them to install.
> 
> I ended up paying $650 labor for mine but I'm in a somewhat rural midwest area where cost of living is fairly low. The $1100 estimate might be very reasonable for your area. It really does cost a lot to run a business - much more than just paying an employee his hourly wage while he's at a customers house.
> 
> You want to make sure you replace a bad exchanger right away cause they can be deadly and make sure you have good carbon monoxide detectors.
> 
> Good luck


If its an 80% Im going to guess a 20 year warranty on it,some of the 90 plus units were lifetime.
I used to warranty out a ton of the old trane 80% heat exchangers for cracks,the trane wreck dealer in omaha used to hate me back in the day.:laughing:


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## plummen

poppyo said:


> 90 percent plus is the only way to go.You Will be paid back in $$$$$$$$$$$$$$$$$ savings in no time at all


Theres nothing wrong with an 80% furnace,many times its not feasable to install a 90% in place of an existing 80.


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