no heat

[ticktack]

my trane gaspack furnace heat would not come on. replaced thermostat, still does not come on . it will hit and miss at times , but will cut off before set temp is reached. it is 13 years old, never had to do anything to it .would anyone know what i should check that might cause this problem? thanks for any help.

[StanW]

You should have several relays in the unit - I would check them to start.

[satchick]

Might also be the flame sensor, as they do get dirty or corroded over the years and require cleaning, or replacement. If the sensor goes bad, it won't sense the heat from the main burner, which will cause the controller to shut off the gas flow. Since yours is 13 years old you might as well replace it, since they're cheap.

When you say you haven't had to do anything to this unit..... Have you at least had it cleaned and serviced? If it hasn't even been cleaned in 13 years, the pilot, burners, and ignitors could be too dirty...

[rick_d]

At 13 years old your best bet is to call a professional. You don't want to risk Carbon monoxide poison. More than likely at that age the heat exchanger is is cracked / rusted out. A package units life span is a lot less than that of split system. being that the unit is subject to the elements. I see on average the life span of a pkg unit is 7-10 years. unless they have stainless steel heat exchangers.

[ticktack]

thanks satchick, it was flame sensor. cleaned it , back in heat. also thanks to all who responded. any could have been right about the problemn. satfix is the one and only. saved me a big cost from a professional, money i didn't have to start with.thanks again to all.

[satchick]

Even though it's fixed now, I would still recommend having a professional inspect the unit before it starts to get cold out. There could be other problems with the furnace or chimney that could pose a safety issue (CO poisoning being the big one).

[Mondoman22]

I would also recommend
Cleaning the Pressure Switch and Tube and port...
There is a pressure switch with a rubber tube hooked
to it... It can also give you sporadic Operation... The
Ycc Gaspacks do that alot as well as the flame sensor...
and like others have mentioned... I would most likely
get it serviced by a professional....

I do heating and air for a living, Gas pressure has to be
checked 3.5 inches water column "Natural Gas" Also
the top should be taken off and the chambers Inspected
and the Burner faces Wire brushed and Cleaned... Very important
to have the chambers inspected at 13 years old... They are known
To Crack where the chambers form a 90... Important to have it
inspected don't pay to much a service like that should be between
69 and 89 dollars and make sure they take the top off.. If they don't
Throw them out the yard...

Tony

[JCO]

You never answered if the unit had been cleaned in its 13 year life span.. If it hasnt being an atmospheric burner its easy to use a brush and clean the burner.. Check the flame color it should be blue.. If you see orange or yellow your combustion is off or the burners is clogged.. Checking the heat exchanger for cracks is also a good idea, someone mentioned CO leaks those are deadly.. Check the chimney for soot and birds nests.. As for the gas pressure most regulators in the units are good enough they will work with a wide latitude at the input.. If the pressure is off it will be visible in the flame color ..

If you have to play with the gas piping call in a proffesional, teflon tape doesnt cut the cheese when reconnecting fittings.. LOL