they are right if it is over 20 years old... '

High efficacy and direct vent is the way to go with a gas furnace these days. (I spent over 25 years lining chimneys for gas furnaces and never do now)

One important factor with these new gas furnaces is the combustion air should be brought in from the outside.... especially if the furnace is near a laundry.

One bad part is they don't last as long as the old 'inefficient' ones.... expect 10 maybe 15 years out of one.

quote:

Originally posted by Excam_Man:

quote:

Originally posted by calugo:
I'd be interested to know what manufacturer builds the best natural gas furnace and if it's a DIY installation.

The best furnace manufacture will be the guys/gals name who comes in and does a load calc on the structure to properly size the unit to the homes requirements. Insures the ducting will support said unit. Installs it correctly, making sure everythings up to code. Sets it up properly to insure its running with-in the manufactures specifications and insures its running safely. In a sense, finishing the manufacturing process on site.

If you have to ask if it's a DIY project, the answer is no.

Now, if you have all the knowledge and skills to do a manual J, manual D, electrical, gas line, venting, sheet metal, drains and control work, along with all the required tooling;
Electrical tools/meters
Piping tools
Sheet metal tools
Plumbing tools
Gas pressure meters
Temperature meters
Combustion analyzer

You definately wouldn't be asking if it was a DIY project.
This isn't "plug and play" equipment.

Well that's not what I wanted to hear but thanks just the same, very valuable information. Looks like I'll be looking for a quality contractor.

quote:

Originally posted by Blume9mm:
they are right if it is over 20 years old...
expect 10 maybe 15 years out of one.

Horseshit

When they only last 10-15 yrs, its because they weren't done right or its been running with plugged up filters for most of its life.
20 yrs+ should not be a problem for a properly working furnace with regular filter changes.

40-60 yrs for cast iron boilers.

Equipment should get replaced when it's no longer safe to be in operation or when the cost of repair vrs replacement makes no sense. Replacing due to age alone is completely insane.

I chose to replace before required.

I chose Daikin (Japanese owned).

I chose two-stage variable speed 96%.

I do not regret any choice.

We bought as a long term investment.

The best in this area was a “Lennox Premiere” dealer that came in $2k less with rebates only they offered. They did detailed quotes and built in to their price an extra 3 years “Comfortshield” labor warranty plus did a few years free maintenance. They came back out and insulated the unit for free when it sweated in the garage install.

That sealed the deal over the other companies quoting.

Basically, go with a good installer that stands behind their work, has plenty of good reviews and is willing to give you multiple quotes to meet your budget.

We went 2 stage variable and it probably is a tiny bit more comfortable but overall, a single stage would have been acceptable.

What’s up with your current furnace? Looks newer and can probably be fixed for less than new.

quote:

Originally posted by Excam_Man:

quote:

Originally posted by Blume9mm:
they are right if it is over 20 years old...
expect 10 maybe 15 years out of one.

Horseshit

When they only last 10-15 yrs, its because they weren't done right or its been running with plugged up filters for most of its life.
20 yrs+ should not be a problem for a properly working furnace with regular filter changes.

40-60 yrs for cast iron boilers.

Equipment should get replaced when it's no longer safe to be in operation or when the cost of repair vrs replacement makes no sense. Replacing due to age alone is completely insane.

Maybe the new ones.. but the first high efficiency ones they built in the late 90s did not even last 10 years.... Planned Obsolescence is a real part of manufacturing now.... I installed a gas water heater a number of years back with a 8 year warranty.. it died at 9 years....the average American home sells every 7 years... make an appliance that last 10 and the averages are with you.

Amana furnaces have a good warranty.

Product Limited Warranty

The heat exchanger on this gas furnace is covered by a Lifetime Limited Warranty*. In addition, all functional parts are covered by a 10-Year Parts Limited Warranty*. For a full description of all warranties applicable to this product, please see your local Amana brand dealer or click on the consumer brochure and product warranty links above.

https://www.amana-hac.com/prod...s92#limited-warranty

quote:

Originally posted by Blume9mm:

Maybe the new ones.. but the first high efficiency ones they built in the late 90s did not even last 10 years....

Then I must see the "special ones" which are still in operation today. Making them 25-30 yrs old.
Sorry, but your theory isn't reality.

Furnaces and air conditioners get changed out all the time when the "so called techs" don't know how to repair them. Doesn't make the equipment garbage.

quote:

Originally posted by wcb6092:
Amana furnaces have a good warranty.

Its not just Amana, most every HVAC manufacture provides a 10 yr parts warranty with proper registration.
Limited lifetime heat exchangers are pretty normal for mid to high tier equipment.

quote:

Originally posted by Excam_Man:

quote:

Originally posted by Blume9mm:
... the first high efficiency ones they built in the late 90s did not even last 10 years....

Then I must see the "special ones" which are still in operation today. Making them 25-30 yrs old.

Rarely do I get in the middle of a plumbing "discussion". But I do clearly remember the first generation of condensing furnaces having heat exchanger issues. They did not hold up. Eventually coatings, materials, and manufacturing methods progressed to the point that today's heat exchanger is exceptionally reliable.

I work on a lot of furnaces that are a lot older than that, and look way worse! I bet some of my customers would give their left one for your furnace.

Some of the less scrupulous companies in these parts would take that one out and sell it to someone who can afford new.

There is no way for a forum reader to know who is giving good advice or total bullshit. Even people who are trying to be helpful can be very wrong. it seems to get down to the person that spews the most on a topic is deemed an expert and believed. Beware of asking for help from a bunch of well meaning folks on the internet.

quote:

Originally posted by Stlhead:
There is no way for a forum reader to know who is giving good advice or total bullshit. Even people who are trying to be helpful can be very wrong. it seems to get down to the person that spews the most on a topic is deemed an expert and believed. Beware of asking for help from a bunch of well meaning folks on the internet.

I would pay attention to what Excam says on the subject.

I sell about $10million a year in hvac equipment every year, mostly commercial though.
I am NOT a tech/installer, but have seen most of the mistakes that can be made, and have went behind some amazingly incompetent contractors.


When friends ask what to buy, I ask them who's doing the work first. As Excam says, doesn't matter how good/bad the equip is if it isn't sized and installed correctly.

If the existing system had good airflow and controlled temp/humidity satisfactorily throughout the house I would have no problem replacing with same size units and calling it a day.

New ductwork, or a problem system should get redesigned from scratch, starting with a good load calc.

quote:

Originally posted by Stlhead:
There is no way for a forum reader to know who is giving good advice or total bullshit. Even people who are trying to be helpful can be very wrong. it seems to get down to the person that spews the most on a topic is deemed an expert and believed. Beware of asking for help from a bunch of well meaning folks on the internet.

Can you address/counter anything the man is saying in this thread?

quote:

Originally posted by Excam_Man:

quote:

Originally posted by wcb6092:
Amana furnaces have a good warranty.

Its not just Amana, most every HVAC manufacture provides a 10 yr parts warranty with proper registration.
Limited lifetime heat exchangers are pretty normal for mid to high tier equipment.

Keep in mind the main word is 'Limited'..... a new type of stainless steel had to be invented for these high efficiency gas furnace heat exchangers.. the first ones rotted out in a couple of years...
AL29-4C

quote:

Originally posted by Stlhead:
There is no way for a forum reader to know who is giving good advice or total bullshit. Even people who are trying to be helpful can be very wrong. it seems to get down to the person that spews the most on a topic is deemed an expert and believed. Beware of asking for help from a bunch of well meaning folks on the internet.

Four well-intentioned sentences. 1] True, but track record counts. Most of the information posted is verifiable. 2] Very true. I often encounter people who learn something wrong, and still stick to their guns. Heck, when I was a kid, I was convinced meat came from both animals and grew on trees. Maybe it was a picture of giraffe meat drying on a tree in Africa, a few chapters ahead in social studies, which I saw. 3] Maybe on a superficial level, but eventually a few well-placed words by someone with experience can set the boat on course. 4] As forum lawyers & doctors often tell us. And we respond with real-life experiences, to temper the caution of their real life experiences.

This is an interesting topic because of the vast leaps home comfort systems have achieved in the past couple of decades. Excam_Man makes an excellent point, "Then I must see the "special ones" which are still in operation today. The earliest high efficiency furnaces which failed in 4-10 years were replaced decades ago, and he sees the statistical remainder. Like we used to say, 4/5 RUDD AC condensers failed within 10 years, and the fifth would be running fine 20+ years.

Excam_Man is indeed seeing the "special ones". They do exist. If you read every post, you'd know my dad's furnace looked like crap for decades but passed the CO test. Rusty cabinet, solid heat exchanger. At my advice, about the only moving advice he took, dad left replacement to the new homeowner.

No one has addressed the chimney code issue if the atmospheric vent furnace goes direct vent. Chimneys are sized for the BTUs going into them. Remove 100k-120k heat, and the chimney is now oversized for the "remaining fixture", in this case likely the 40k BTU water heater (called a hot water heater among purists ). The oversized chimney will cool the WH flue gas to the point condensation becomes a structural issue, as well as a code issue.

A large company (I worked for Sears for a while in HVAC sales) would not swap a chimney vent ("atmospheric vent" or "AV") furnace for a direct vent furnace unless we were installing a chimney liner to reduce chimney diameter OR a DV WH was being installed to replace the AV WH.

One of the most amazing things about the newer systems is that you can have your t-stat control summer humidity independent of temperature very economically. Low ECM fan operation + coil evap cold = removes humidity very cheaply. Give me 78˚ and 50% humidity, over a short-cycling 68˚ living room any day.

I had a forty year old furnace in my old house. Every year I would inspect it myself for obvious defects. On fall I saw the burner had leaks, that is, flames were coming from cracks in it. I shut it down and had it replaced with a modern, higher efficiency furnace. My gas bills went from around 500 a month to around 180 a month in winter. The replacement cost me 4k or so, but it was well worth it, for me, to reduce those gas bills.

I concur with having the engineering guy come out and run calculations on your house to determine the correct sizing, etc.

My new home needed both units replaced (heat pump, not gas.) Both units were replaced in a total of 5 hours. They were almost "slip in" style.

14 months later one unit failed. The service guy said the cheapest solution was replacing the outside unit. He did, no charge. Said it would run his company more in labor to repair than to replace.

My earlier post was more inflamitory than it needed to be, and did not address the OP’s questions.

If the OP was a friend of mine I would suggest he get another bid. I would only consider a Carrier or a Trane furnace, single speed, single stage, preferably non ECM fan motor. No need for a load calc if a knowledgeable person looks at the place and confirms that the house really needs a 90k, odds are it would be better served by an 80k unit, but in practice most folks won’t notice a difference, and it won’t effect your gas bill in any case. If you like your stat keep it, but I am not a fan of the so called learning stats and don’t recommend or install them, far too many complaints for no gain.

To head off the what brand is best question my answer is simple, I don’t care, the top two are nearly equal in “goodness”, and they are the top two so why would I recommend or install anything else when they cost the same and are the top dogs? Why get a Chevy if a Caddie is the same price? Even if they are the exact same car made in the same factory?

Single speed and single stage because the juice is not worth the squeeze, and added complexity means added repairs.

ECM motors are very efficient, and supper flexible. They also don’t last very long and cost a ton to replace. I only put them in when forced to be hippie tree hugger codes.

Why no load calc? Because an experienced guy did so fucking many of them in the first 2 years he was selling that he can size a furnace from the street. If your estimator can’t size the furnace after a quick tour of the house why would you trust anything he says?

As to why anyone should care what my option is on this, all I can say is that I have been in the HVAC business full time since I was 14 and have gotten pretty good at it. Even so, don’t rely completely on any info that you get from anybody use your personal judgement and go with what you think is best, after all its a furnace, not that big of a deal in the grand scheme of things.

Two most important things you can take from this posting... you can take this to the bank.
When a tech says this brand is better than the rest, you can move on... don't get me wrong, every tech has their favorite, but a knowledgeable tech knows it really comes down to the tech and not the brand.
When a tech says, I've been doing this since -xx- or I've been doing this for _xx_ many years, you can normally move on... again, dont get me wrong, experience helps. But years of doing something wrong can not make up for proper training, work ethics and continued education.

quote:

Originally posted by Stlhead:
My earlier post was more inflamitory than it needed to be, and did not address the OP’s questions.

If the OP was a friend of mine I would suggest he get another bid. I would only consider a Carrier or a Trane furnace, single speed, single stage, preferably non ECM fan motor. No need for a load calc if a knowledgeable person looks at the place and confirms that the house really needs a 90k, odds are it would be better served by an 80k unit, but in practice most folks won’t notice a difference, and it won’t effect your gas bill in any case. If you like your stat keep it, but I am not a fan of the so called learning stats and don’t recommend or install them, far too many complaints for no gain.

To head off the what brand is best question my answer is simple, I don’t care, the top two are nearly equal in “goodness”, and they are the top two so why would I recommend or install anything else when they cost the same and are the top dogs? Why get a Chevy if a Caddie is the same price? Even if they are the exact same car made in the same factory?

Single speed and single stage because the juice is not worth the squeeze, and added complexity means added repairs.

ECM motors are very efficient, and supper flexible. They also don’t last very long and cost a ton to replace. I only put them in when forced to be hippie tree hugger codes.

Why no load calc? Because an experienced guy did so fucking many of them in the first 2 years he was selling that he can size a furnace from the street. If your estimator can’t size the furnace after a quick tour of the house why would you trust anything he says?

As to why anyone should care what my option is on this, all I can say is that I have been in the HVAC business full time since I was 14 and have gotten pretty good at it. Even so, don’t rely completely on any info that you get from anybody use your personal judgement and go with what you think is best, after all its a furnace, not that big of a deal in the grand scheme of things.

That all sounds nice, but really is a bunch of blah, blah, blah.

Let's take the "only consider Carrier or Trane" comment.
UT (United Technologies) owns both Carrier and ICP.
Carrier Corp manufactures furnaces under the labels of Carrier, Bryant, Payne and the old Day & Night.
ICP manufactures furnaces under the labels of Arcoaire, Comfortmaker, Day & Nite, Heil, Tempstar, KeepRite, Lincoln, etc.

Ingersoll Rand is the American Standard Co., manufacturing furnaces under Trane and American Standard.

That's 12 plus brands under two manufactures, but you say there's two top brands?
What makes Carrier any better then the other (10+) sister brands, since it is only a label change?
And your kidding yourself if you think they all cost the same. One big factor which increases pricing is advertisment.

That's not even taking in consideration improper sizing, installation and set-up. Afterall, improper equipment installed wrong is just another piece of shit waiting to fail.
Limiting yourself to single stage equipment also compromises comfort.

Now we have this interesting comment, "confirms that the house really needs a 90k, odds are it would be better served by an 80k unit, but in practice most folks won’t notice a difference, and it won’t effect your gas bill in any case"

It requires 90k, but 80k will work? If 80k will work it sure as hell didn't require 90k now did it?
Most folks won't know the difference? Sure they will, when their house isn't as comfortable as their families, friends, co-workers, etc. Or when they have several failures, since their normally under sized ducting won't allow for enough air flow for the larger equipment.
And it won't effect gas bills? Short cycling most definitely effects operational costs. Not only in fuel consumption, but in starting and stopping of electrical motors.
Why do you think a vehicles MPG is different for city vrs highway? Same principles apply to heating and cooling equipment.

The next paragraph is a bunch of non sense as said before, all brands don't costs the same, even though they can be identical.

Now comes "Single speed and single stage because the juice is not worth the squeeze, and added complexity means added repairs."
So, ones comfort is not worth the squeeze? I believe this would be a personally choice best left for the client to decide.
Complexity? So modern vehicles are no more reliable then an old model T ? Do without power steering, cruise, delay wipers, power windows, because it will be added repairs. However, these features rarely fail... and most folks won't know if they have it or not (or will they).

"ECM motors also don’t last very long"
Definition of long would be required. If needed, most have a 10 yr warranty if the product is registered. And it's not like they have a high failure rate.

"Why no load calc?" (because general rule of thumb is good enough and most folks won't know the difference).
True professionals do the job correctly the first time around. So the equipment not only lasts, provides years of troublefree service and provides the best comfort for the end user.

"it's just a furnace, not that big of a deal in the grand scheme of things."
It's only the single most expensive appliance in ones home which provides heat. Something which most people would consider to be a big deal especially the further north one lives.

"I have been in the HVAC business full time since I was 14"
Couple things come to mind... most people here wouldn't have a clue to your age to know total years in this business (not that it matters, see my opening comments).
The next thing which is always a factor, just because someone does something a certain way for years, doesn't mean they have been doing it correctly all those years.
I personally don't care how long someone has been in the business, if they don't know what they're doing. It only proves they've been doing it wrong for -xx- amount of years.
Equipment, codes and practises are continually changing, requiring continued educate and the flexibility for businesses to change with them. Something that was normal yesterday could very well be wrong today.

What really matters is track record and verifiable information. Does the person normally know what their talking about or do they have a habit of saying off the wall shit?

Excam_Man,

I'll have to back up a bit and say it sure looks like you know what you are talking about... does not mean I'm admitting I was wrong about those first high efficiency units though... then again I've seen them vented to masonry chimneys ... around here it's not that odd to see an old furnace just vented to a hole in the wall... for years I had to deal with Cat 1 furnaces vented improperly... now I have to deal more with negative pressure in the house because of an unbalanced system... which I just pass the buck on. People usually don't like it when I say just open a window and that will actually 'solve' the problem. Then I didn't start in the chimney business until I was 25... still am in the business even though I'm also on Social Security now.....