Anybody know anything about furnaces? i'm cold..

[Thaco]

hey all, lookin for a little advice, i am no Baller like the rest of beyond so i need to find a way to fix this easily/cheaply... i woke up this morning and i am cold. i live in a condo, so we steal heat from the surrounding units, but i went to my furnace, and the pilot is on, the fan works fine (there's a manual push button that i can use to test it), the t-stat says it should be heating, but it's not firing up, neither the burners nor fan are coming on when the t-stat commands them to... i know it's not the t-stat because i have taken it apart and jumped the 2 wires, which should make the furnace fire up... but to no avail... what do i need to do? how do i fix it inexpensively?

[Sal0]

I don't got much advice, but my friend had a clogged filter and he had similiar problems. Once he cleaned/replaced the filter he was good to go.

[Darell_n]

You may have one or more safety switches that need to be manually reset by pushing in the button. If you have a meter, check for 120v and 24v on the transformer.

[JAYMEZ]

I had this happen to my furnace (in a new home..) , apparently a fuse burnt out , it was a cheap fix and the furnace has been good since.

[Thaco]

thanks for the suggestions guys, i did look around for some cutoff switches but the only thing i can see at all to manually do anything is the fan auto/manual on switch, which works, the fan will turn on when that switch is moved, but the gas still doesn't flow.

[71/454]

If it still has a pilot it should have a thermocouple I'm guessing. It's been years since I've looked at one, but look right by the flame of the pilot and you should see a little copper bulb thing with a copper tube attached. Basically the pilot heats the copper bulb enough to tell the gas valve to open. Sometimes the thermocouple fails, it was pretty common in older furnaces, thats why they went to igniter bars and piezo. I would take out the thermocouple and go match it up at home depot and change it. Good news is they're cheap.

[Thaco]

I called Atco, they are gonna send someone out for free, all i have to pay for is parts if they have em. Thanks for all the suggestions.

[Thaco]

Originally posted by 71/454
If it still has a pilot it should have a thermocouple I'm guessing. It's been years since I've looked at one, but look right by the flame of the pilot and you should see a little copper bulb thing with a copper tube attached. Basically the pilot heats the copper bulb enough to tell the gas valve to open. Sometimes the thermocouple fails, it was pretty common in older furnaces, thats why they went to igniter bars and piezo. I would take out the thermocouple and go match it up at home depot and change it. Good news is they're cheap.

just looked up the termocouple, i think you nailed it, i turned off the gas so it's cool when the tech gets here, i would change it myself but all the stores closed at 6.

[Darell_n]

Originally posted by Thaco


just looked up the termocouple, i think you nailed it, i turned off the gas so it's cool when the tech gets here, i would change it myself but all the stores closed at 6.

The thermocouple's job is to keep the pilot flame going, that's it.

[71/454]

Originally posted by Darell_n


The thermocouple's job is to keep the pilot flame going, that's it.

ahhh yes. That sounds right. Sorry op, guess it's not your problem. Like I said it's been years. Let us know what it was, now I'm curious.

[Thaco]

That's not the info i was given, i was under the impression the thermocouple's job was to detect pilot and not allow the furnace to fire unless it told the thing that the pilot was lit.

[Aleks]

Originally posted by Thaco
That's not the info i was given, i was under the impression the thermocouple's job was to detect pilot and not allow the furnace to fire unless it told the thing that the pilot was lit.

So did Atco come over last night? Was thermocouple the problem?

[legendboy]

Probably the solenoid valve...

[Zero102]

If it is a newer (last 10-15 years) furnace then it is almost definitely the flame sensor.

Check for blinking lights on the control board to indicate the fault code (they will reset if you remove the cover so you have to look through it first, but the codes will be printed on the board or inside the cover). This will tell you why the furnace is cutting out.

If you have blinking lights that indicate something along the lines of "primary ignition failure" then it is probably your flame sensor. You will need to remove it and clean it.

Without telling us what furnace you have and what (if any) status codes are blinking on the board all anybody can do is guess.

[Thaco]

it's not new, it's ancient, it was put in when the house was built in 79, it's a lennox furnace.

I've got a furnace guy coming, he'll be here in the next couple hours...

[Thaco]

furnace guy came and left, $400 later, i'm warm again, it was the whole valve system that was toast.

[Masked Bandit]

All things considered that's not too bad. I mean the set up is over 30 years old & nothing runs forever.

[Darell_n]

Originally posted by Thaco
That's not the info i was given, i was under the impression the thermocouple's job was to detect pilot and not allow the furnace to fire unless it told the thing that the pilot was lit.

When the thermocouple is bad the pilot flame will not stay lit on it's own. Glad to hear it's working again. It will take a miracle for any of today's furnaces to last 30 years. More like warranty + 1, then $1200 to fix.

[Thaco]

Originally posted by Darell_n


When the thermocouple is bad the pilot flame will not stay lit on it's own. Glad to hear it's working again. It will take a miracle for any of today's furnaces to last 30 years. More like warranty + 1, then $1200 to fix.

yeah, the furnace guy said if the heat exchanger goes, it's done, it would cost $2500 to fix, IF he could find the parts, which he doubts he could.

also he explained o me how the thermocouple works, kinda stupid IMO, the thermocouple should sense for pilot, if no pilot, then the thermocouple should shut off the gas entirely...

[Tik-Tok]

Originally posted by Thaco

also he explained o me how the thermocouple works, kinda stupid IMO, the thermocouple should sense for pilot, if no pilot, then the thermocouple should shut off the gas entirely...

It does. The heat from the pilot sends the signal to the valve, through the thermocouple, so it will open when it's supposed to. If there's no heat at the pilot, the thermocouple won't let the valve open, and no gas goes to either the burners, or the pilot.

That's why you have to hold the separate gas button down when lighting the pilot.