HVAC guys, need some help

Aharami

Lifer
Aug 31, 2001
21,205
165
106
About an hour ago, I noticed that the heat is not working. Went up to the attic to find the pilot light has gone out. My unit has an automatic pilot light switch and I followed the instructions to turn it off, wait 5 mins, and turn it back on again. Yet I dont see the pilot light coming back on.

I have placed a call to PSE&G and they will have someone out here tomorrow morning. Until then, there's nothing I can really do as I dont know HVAC systems at all. It's pretty cold out tonight and I expect the house to get into the low 50's high 40's by tomorrow morning (usually keep it at 65, it's already down to 60). So can some experienced guys here shed some light on some possible reasons for the pilot light to go out and not turn back on?
 
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bobdole369

Diamond Member
Dec 15, 2004
4,504
2
0
With no pilot within a minute or 3 the gas smell becomes obvious. I may not be up on current gen stuff being from FL, but I recall this from when I was a teen in michigan.

Don't use a match.
 

AlienCraft

Lifer
Nov 23, 2002
10,539
0
0
thermocouple failure?
That's the control device that tells the gas valve that there is a flame present, and to allow gas to flow. It sticks into the area where the pilot flame would hit it.
 

AlienCraft

Lifer
Nov 23, 2002
10,539
0
0
If it has an 'instant on' lighting system, the control module may have gone. This happened to our unit.
 

Aharami

Lifer
Aug 31, 2001
21,205
165
106
not gonna try to light it manually. It says so in big red letters on the instructions. Did some googling and Im guessing it is probably a thermocouple failure
 

olds

Elite Member
Mar 3, 2000
50,120
776
126
thermocouple failure?
That's the control device that tells the gas valve that there is a flame present, and to allow gas to flow. It sticks into the area where the pilot flame would hit it.
This, if the gas is on.
 

T9D

Diamond Member
Dec 1, 2001
5,320
6
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Sometimes there are filters actually in the unit. If it gets to clogged and to hot it shuts everything down. Might not be it but thought I would throw that out there. I installed a furnace in my parents house and they never changed those filters and that happened to them. There was some reset switch some place.
 

Aharami

Lifer
Aug 31, 2001
21,205
165
106
should I keep the pilot light switch in the off position until it gets serviced tomorrow morning? I mean can the gas leak out if the switch is on and the light is off?
 

AlienCraft

Lifer
Nov 23, 2002
10,539
0
0
Also should I turn the gas valve off going into the pilot light?
Not unless you smell it really strong. Your problem is the gas does not flow because it's control is closed., not open, in which case you would have heat.
 

Ozoned

Diamond Member
Mar 22, 2004
5,578
0
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A lot of the modern units have indicator light on a printed circuit board that will flash in a certain order in the event of a problem. The falure problem or instuctions for the flashing code is usually on the back of the access panel that you take off or with the wiring schematic. Your may or may not have that feature.
 

drnickriviera

Platinum Member
Jan 30, 2001
2,456
266
136
Well if it has an auto pilot, it probably doesn't have a thermocouple. It will use a flame sensor.

I'm guessing the coil ignitor. They take AC current and glow red hot to light the gas. Pretty fragile and crack easily.
 

Rubycon

Madame President
Aug 10, 2005
17,768
485
126
Your flame rod may not be touching the pilot any more. When's the last time maintenance was done? The (pilot) flame should be long enough to reach the flame rod and blue (never have a yellow tip).

If you're not familiar with any of this (or troubleshooting flame safeguard controllers in general) you are best waiting for a qualified service person to arrive.
 
Nov 5, 2001
18,366
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Well if it has an auto pilot, it probably doesn't have a thermocouple. It will use a flame sensor.

I'm guessing the coil ignitor. They take AC current and glow red hot to light the gas. Pretty fragile and crack easily.


they also get covered in corrosion. A common fix is to lightly sand the igniter to remove corrosion. Ours did this just last winter, and I know of several others who had similar issues. One of the first things to check, free and easy. If it's cracked, it's an easy replacement as well.