Furnace Problems

[Webbe]

Hello,
Have a furnace problem and know very little about them.
Planning on having it fixed by a HVAC company and have had
someone look at it but would like to know if what they have said
sounds right before I pay for a second opinion.
The reason I called them out was last winter my pilot light keep going
out and actually it was the winter before just not as bad. It occurs
when the furnace goes off and is off awhile (meaning that it warms up
and is not on as much) and actually it did this the year before that just
not as bad.
They are telling me it could be one of 3 things -the thermal cup, the heat
exchanger and some other part that has to do with the wiring.
Their is also another problem for about a year or so there was water on
the floor by and under it but since I have a few basement leaks I was not aware it was from it plus it is a older home and the air conditioner hose goes from it to a sump pump. He is saying that the burners are corroded and need replaced and has affected the flame color.
But regarding the first problem, he is saying that the heat exchanger could be cracked and that by law or rule of his company that has to be checked which means mainly taking the furnace apart. He checked on the heat exchanger and it is under warranty to the extent that it will be prorated(half covered).
They are giving me a price range of $600 to $1000 depending on what it is but won't know until they get into it-that includes replacing the burners and labor. He though has also gave me a price of a new furnace for about
$1,700.
The furnace is about 15 years old (also the central air) and it is a Janitral
(not sure the spelling). Don't know the BTU but believe it is around 75. My house if around 1300 sq feet.
Was not planning on getting a new furnace at this time but obviously don't want to put $1,000 in to a 15 year old furnace. Have considered
having a second company look at it but then there is the $60 service charge.
Does all this sound right? Any input would be appreciated.


Webbe

[HayZee518]

heat exchangers do go bad but at what frequncy I do not know. a cracked exchanger is dangerous in that any unburned fuel gases go into the air plenum through the fan and contribute to a high co-2 concentration. as far as the pilot flame color, that depends on the air/gas ratio. too much fuel and not enough air produces an orange flame. a proper mixture is a deep blue outer flame with a lt blue inner flame, no yellow or orange tips. the condition of the pilot flame jet is immaterial. rusted / corroded.

[596]

Pilot light problem could be dirty pilot burner, or defective thermocouple. But hopefully he checked these, and it can be other more serious problems.

RIGHT NOW, you should get a Carbon Monoxide alarm from the nearest hardware store. Any talk of a bad heat exchanger raises the question of CO, so for less than $20 , protect yourself.

If you don't have confidence in the contractor, get a second opinion. Nothing wrong with that.

The life expectancy of a furncace is probably 15 to 25 years. It would be a close call as to whether to spend half + the cost of a new one, to get 10 more years of service. It probably would make sense. But if you are in postition to spend a little more on a new 90+ % furnace, you would recoup some of the cost over the years in energy savings.

[Webbe]

Hi,
Thanks for the reply's.
The biggest problem that I have with the contractor is he is saying he does not know what is causing the pilot light problems-that it could be
this or that. But he did not check or test anything.
He is saying he would have to check the heat exchanger which means the furnace would need to be taken a part due to the pilot light color
not right and the corrosion on the burners. So even though the burners
are rusted that could or would not create a problem?
I do have a carbon tester but it is upstairs and not in my basement.
What does 90+ % furnace mean?

[HayZee518]

first of all dump your contractor. if he's just guessing about the pilot light he don't know much about heating devices. It would seem a shame to tear apart your whole system just to look at the heat exchanger and or the pilot or main valve and burner. I spent nearly a half day troubleshooting a guys furnace one day only to find out his blower motor had one winding open and shorting to ground. IF you have proper gas pressure and the pilot valve is functioning, then there's no reason why it would fail. a millivolt flame detector keeps the pilot valve open. It generates a DC voltage and is connected to the pilot valve. Inside is a very small electromagnet that sucks in and holds a metal valve plunger against a spring tension. the pilot doesn't use a mixing orifice - it just burns gas - no air. your main burner DOES mix air and gas to properly burn with little carbon monoxide emissions.

[Webbe]

Well what he said that sounded odd to me was that due to the burners being corroded and the flame color not right that his company required for safety reasons that he check the heat exchanger but had said it could
be other things that is causing the pilot light problem.
Guess I am going to have to get a second person out here, just didn't
want to have to pay the $60 service call.

Thanks

[Webbe]

Well I did get a second opinion but still not certain what to think.
The guy came out and at first said he though it was the thermal cup and
was going to test or try that then took out the burners and did say they needed replaced and then shined the flashlight up in it and said that the
heat exchanger was cracked and in a couple of places.
The thing is he said that after I ask him about the price of a new furnace
so...... The reason I am questioning this is this pilot light problem has
been going on for at least 4 years just gradually getting worse (last year
it went out more often) Well the furnace is 14 years old and seems kind of
odd that the he exchanger would of cracked 4 years ago when it would of been 10 years old. Said this to him and he said the brand is know for problems. As I have said it is a Janitral.
Does this sound right cause he is saying for the cost might as well get a new furnace.

[HayZee518]

Go for the new furnace. Janitrol is a common name - AO Smith, Beckett, Trane, Honeywell are more common than janitrol. AO Smith has a beefed up heat exchanger that's supposed to last longer. All the heat exchanger is - is a cylinder, closed on both ends [cept for an opening for the burner assembly] and an exhaust to the chimney. Basic operation expands and contracts this cylinder because of heat applied to the inside. radiated heat goes to your plenum for distribution. expansion and contraction does a job on metal. at one point the metal is annealed and softens other parts harden etc. this imbalance in properties causes cracking. you can't get away from it, but the exchanger should last a long time.

[Webbe]

So it would not be worth having the heat exchanger replaced?

[HayZee518]

If it's cheaper to get a new exchanger go for it but I'd ask about a guarantee or warranty on it. are the burner holes enlarged from the corrosion? and what's this "burner cup"? does the pilot flame come out of a brass or steel orifice? If the hole in the pilot orifice is enlarged this could cause problems. Natural gas and LP orifices are different in sizes. check out eBay for a new burner valve and/or burner assembly.

[Webbe]

Thanks for the reply and sorry I don't know the answer to some of those questions-female here.
But one thing I do know is Goodman (Jantrol) is saying since the furnace
is 14 years old they will only refund 50%.
So I have one contractor telling me they don't replace Jantrol h exchangers and recommed a new furnace and the other telling me not
sure what the price would be to fix it $500 to $700 but also recommed a new furnace.
I did call Goodman myself and learned it is a 50% refund on my model.
So really all I am trying to find out is what the typical price is for the h
exchanger and to have it installed and the burners if needed.
Can't seem to get that answer.