New Furnace vs. Repair

[drewink]

I have a builder grade Comfort Maker single stage furnace that has a bad heat exchanger. It is 5 1/2 years old and still under warranty. The part is free, but install is $1500. They gave me the option of replacing, or installing a new Trane 2 stage furnace for $3500. They said that I could save $500-$700 per year with the 2 stage. I have dual zone heating with the second Comfort Maker furnace in the attic. It is working fine. Is it worth having the better furnace installed, or is the guy blowing smoke? I have used this HVAC company for many years, but I know nothing about HVAC except change filters and service twice per year. The total heating area is approximately 3300 square feet. Any help would be appreciated.

Drewink

[trbo20]

Are you getting the replacement part directly from the manufacturer? Did you call around on the labor quote? Ask how many guys they're going to use and how many hours they're charging. I think you'll find prices vary quite a bit.

[Robert Gammon]

Where do you live?? How much do you use this furnace?? (same question posed a different way)

What is the efficiency rating of the furnace with a bad heat exchanger and what is the efficiency of the new unit?

Until we know the answers to these questions, we can't possibly answer your question.

You MUST do something as a bad heat exchanger is DEADLY.

Efficiency ratings of the old furnace and the new one and how much you use the furnace will tell you how long the payback is on a new furnace.

5.5 years is an unusually short lifetime on a heat exchanger. Did he say what was the likely cause???? Suspicious minds want to suggest that either the the builder grade furnace is really low grade or defective from the factory (possible, but doubtful), or the HVAC guy is not telling the whole story. Some HVAC service people have been know to stick screwdrivers thru the heat exchanger just to promote a sale. Well actually, a good heat exchanger will stand up to a moderate blow from a flat head screwdriver. A heat exchanger that is dangerously weak with rust will fail in these conditions.

Did he SHOW you the hole, or did you see it first and call him????

[Stubby]

Is there a safety consideration when you have a bad heat exchanger? Can carbon monoxide get pumped into your living area?

Robert Gamm>> I have a builder grade Comfort Maker single stage furnace that has a

[JoeSpareBedroom]

Based on my experience, raw gas. Fun.

[JoeSpareBedroom]

Saturday, I stopped at my heating contractor's store for a filter. Their posted labor rate is $85 per hour. Any idea what yours charges?

[drewink]

I live in Maryland so the usage for heat is up to 8 months per year. He did not show me the hole. He said it was rusted. I did have a leak from a clogged drain last year. He found it during the fall inspection. The efficiancy on the old unit is 80% (Comfort Maker FBF Series). The proposed Trane is also an 80% but 2 stage vs. 1. Summers are hot so AC runs constantly for 3 months.

[drewink]

Gas is OFF! House no go boom.

[Puddin' Man]

5 1/2 years sounds like "way too little" for Maryland.

$1500 labor-only sounds like "way too much" from the folks that installed the old unit.

I'd either learn to check the HE myself or get a recommend from a neighbor/friend and have a different contractor take a peek at it.

To check yourself, you'd need a hinged mirror kinda like the dentist uses, and screwdriver/wrenches to remove some furnace components fastened with sheet-metal screws. Folks in this forum can help with instructions.

Regards, Puddin'

Pease pudding hot, Pease pudding cold, Pease pudding in the pot Nine days old.

[DK]

You have been punked!

There is no such thing as a bad heat exchanger. It is just a ploy by hvac criminals to get your money.

Think about it. So what if the heat exchanger leaks. There are millions of homes heated by natural gas and propane that dump 100% of the flue gases into the home.

And funny thing is, they have been using this heating system for a couple of hundred years without a problem.

The only precaution I suggest you use is to buy a couple of detectors and hang one near your bed and another in your living quarters down low. Many are made to plug in the wall socket and are just the right height to give you an early warning.

Their solution: $1500. Mine: $40.

[drewink]

I asked for a breakdown of labor. 2 men. $95 per hour. 8 hours each plus $200 for misc. gasketing and admin. I think I need a new contractor.

[JoeSpareBedroom]

Really?

[Robert Gammon]

Is DEATH due to carbon monoxide poisoning a safety concern????

People die from this every year in areas where natural gas and propane air furnaces are used.

It is the SINGLE biggest risk with these units, not reliability of supply, not fire, not explosions.

[Robert Gammon]

House never go boom, gas valve will not allow gas to flow unless hot surface igniter reaches flash point temp for gas.

Raw gas is VERY unlikely EVER leak into a home, UNLESS an earthquake, tornado, hurricane, plane crash into house... happens

[HeyBub]

Sure. Many millions more use burning sticks, dried camel dung, charcoal, whatever.

[Robert Gammon]

Rusted does not make a bad heat exchanger. Rust can accumulate for MANY years before the heat exchanger will leak combustion products to the house. Just because it has rust on it does not mean that it is defective.

In southern texas, we use the furnace lightly for three months, and run the AC a few hours a month EACH AND EVERY month. Some homeowners here sweep out the flaked off rust for several years before they replace. YMMV, so what we do here is NOT a wise practice everywhere.

Given your usage, you should ask about the delta cost of a condensing furnace. 90+% efficient. The extra 13-15% increase in efficiency could have a relatively quick payback if you elect to replace.

[MLD]

My furnace was about one year old when it sprung a leak in the condensate tank (??) within the furnace. Rather than go for a tear down of the furnace to fix/replace, Trane offered a replacement (similar) furnace. I took the new furnace. Have you tried calling Trane direct? MLD

[hallerb]

Leaky heat exchangers can and do KILL!!

Do get quotes for NEW 90+ and compare to your contractor

do you use bleach or other chemicals where your furnace is?? they are associated with premature heat exchanger failures.

if this is the case you may may be better off with a 90+ that uses outside air for combustion.

get your chimney checked BEFORE buying new furnace! If your chimney has troubles go to 90+ direct vent

[DK]

No, they don't. Never have. Never will!

It is just an old hvac sales ploy to take money out of your pocket and put in their pocket.

Here is a picture of a unit that dumps 100% of the flue gases directly into the living quartes.

[Todd H.]

Yup, that's the primary concern. I have a coworker that was very close to dying along with his whole family as a child as a result of a cracked heat exchanger and CO poisoning .

-- Todd H.