Quantcast
Lennox Furnace won't light up - Page 2 - Beyond.ca - Car Forums
Page 2 of 4 FirstFirst 1 2 3 ... LastLast
Results 21 to 40 of 75

Thread: Lennox Furnace won't light up

  1. #21
    Join Date
    Mar 2004
    Location
    Calgary AB
    My Ride
    2020 Subaru Forester Sport
    Posts
    2,969
    Rep Power
    41

    Default

    Originally posted by rx7_turbo2

    Unless you have a manometer(edit* day late dollar short)I wouldn't. You may end up just complicating any future troubleshooting.

    Maxt mentioned earlier you have to find out if the gas valve is getting 24v and remaining closed, or does a loss of supply voltage cause the gas valve to close? This will help eliminate/confirm the gas valve as the issue. The fact you described the loss of flame as "abrupt" suggests there's a fault somewhere else that causes the gas valve to close.
    I got a recording going of the whole setup right now, hoping to catch the voltmeter when the flameout happens or when it doesn't ignite. Voltmeter is permanently hooked up right now to the gas valve and right in front of camera.

  2. #22
    Join Date
    Jul 2010
    Location
    Homeless
    My Ride
    Blue Dabadee
    Posts
    9,599
    Rep Power
    100

    Default

    Originally posted by GOnSHO
    had the same issue, ended up being my blower motor.. no movement of air, flame kept going out.

    $900.00 to fix/replace
    +1 had that 2 years back. Kept throwing overheat codes and ESD. Power cycle it would run for another hour or 2 but eventually ESD ( with ESD it will stop trying ). Big bucks to fix.

    Was a brand new furnace too (just out of parts warranty). I had action furnace fix me up and they were great, no issues since.
    Originally posted by Thales of Miletus

    If you think I have been trying to present myself as intellectually superior, then you truly are a dimwit.
    Originally posted by Toma
    fact.
    Quote Originally Posted by Yolobimmer View Post
    This quote is hidden because you are ignoring this member. Show Quote

    guessing who I might be, psychologizing me with your non existent degree.

  3. #23
    Join Date
    Jul 2013
    Location
    Calgary / Alberta
    Posts
    155
    Rep Power
    0

    Default

    Ya so your high limit switch may be kicking out too, causing gas to shut down. But that doesnt explain the 3-5 failed restarts, as it should have cooled by then. Your fault code isn't specific enough to pinpoint the issue. Could even be an issue with your board as operations are abnormal. Your blower shouldn't shutdown until well after the flame has gone out. Blower eventually shuts down once all the residual heat on your heat exchanger is expelled and the low limit kicks in. How clean is your filter, always check that first(dont know if you mentioned that already). May be time to call in a pro tech.
    Last edited by jeffh; 12-05-2016 at 11:49 AM.

  4. #24
    Join Date
    Mar 2004
    Location
    Calgary AB
    My Ride
    2020 Subaru Forester Sport
    Posts
    2,969
    Rep Power
    41

    Default

    Originally posted by jeffh
    Ya so your high limit switch may be kicking out too, causing gas to shut down. But that doesnt explain the 3-5 failed restarts, as it should have cooled by then. Your fault code isn't specific enough to pinpoint the issue. Could even be an issue with your board as operations are abnormal. Your blower shouldn't shutdown until well after the flame has gone out. Blower eventually shuts down once all the residual heat on your heat exchanger is expelled and the low limit kicks in. How clean is your filter, always check that first(dont know if you mentioned that already). May be time to call in a pro tech.
    My fan never shuts down, the one time I was there watching the flame, the flame died (unfortunately I didn't have voltmeter hooked up at that point) but the fan kept going. It right away did the re-ignition sequence and it ignited the flame again, but the furnace fan kept going the whole time (main blower fan).

    I just called Atco and they should be here this evening. I ventured outside and could smell a small amount of gas from a joint by the meter. Hopefully they can look into that and tell me if my gas pressure is normal.

  5. #25
    Join Date
    Mar 2006
    Location
    Calgary
    My Ride
    Cayenne S, 335i Cab
    Posts
    800
    Rep Power
    21

    Default

    I had similar-ish problems a few years back with my Lennox furnace. I came home a few times to a <10C house and found the furnace off. When I restart the furnace I would see the amber, but sometime it would restart back up, sometimes it would require quite a few restart for it to get going. When I do get it working it would work for at most a few weeks or just a few hours. I remember waking up at 6am to <11C morning.
    I tried all the stuff recommended online like replace the filter, cleaning or replacing the flame sensor, turning down the humidity control, etc but no luck. I finally called a tech, half expecting to spend a fortune replacing a control board or something, and turns out one of the tube was clogged with debris, causing water to back up, and shutting off the furnace. He cleaned it out and the furnace been running good since. Took him all of 20 mins including diagnosis.

    The problem is not fully solved as it still happens once or twice a year, but when it does, I just undo that main hose, blow as hard as i could into it to unclog it, restart the furnace, and it would work flawlessly for another 8-10 months. Not ideal but beat buying another high efficiency furnace.

    I hope your problem is as simple as mine.

    Note: just read your last reply. My furnace fan would stay on the whole time too.
    Last edited by RX_EVOLV; 12-05-2016 at 05:39 PM.

  6. #26
    Join Date
    Mar 2004
    Location
    Calgary AB
    My Ride
    2020 Subaru Forester Sport
    Posts
    2,969
    Rep Power
    41

    Default

    Originally posted by RX_EVOLV
    I had similar-ish problems a few years back with my Lennox furnace. I came home a few times to a &lt;10C house and found the furnace off. When I restart the furnace I would see the amber, but sometime it would restart back up, sometimes it would require quite a few restart for it to get going. When I do get it working it would work for at most a few weeks or just a few hours. I remember waking up at 6am to &lt;11C morning.
    I tried all the stuff recommended online like replace the filter, cleaning or replacing the flame sensor, turning down the humidity control, etc but no luck. I finally called a tech, half expecting to spend a fortune replacing a control board or something, and turns out one of the tube was clogged with debris, causing water to back up, and shutting off the furnace. He cleaned it out and the furnace been running good since. Took him all of 20 mins including diagnosis.

    The problem is not fully solved as it still happens once or twice a year, but when it does, I just undo that main hose, blow as hard as i could into it to unclog it, restart the furnace, and it would work flawlessly for another 8-10 months. Not ideal but beat buying another high efficiency furnace.

    I hope your problem is as simple as mine.

    Note: just read your last reply. My furnace fan would stay on the whole time too.
    Sounds like you got the high efficiency model, mine doesn't have any water runoff anywhere unfortunately. There is a little hose between the one small exhaust fan and a pressure switch, but i have removed that to clean it out as I saw someone on Youtube mention it, but mine was clean, nothing to clean at all.

    Hoping Atco guy can shed some light when he arrives sometime this evening.

  7. #27
    Join Date
    Mar 2004
    Location
    Calgary AB
    My Ride
    2020 Subaru Forester Sport
    Posts
    2,969
    Rep Power
    41

    Default

    So the guy came by last night and fixed the small gas leak outside, and did some tests within the house (nothing too scientific....just crank all gas appliances, fireplace, heater and furnace at the house) and everything was fine, so he said doesn't appear to be a pressure issue. He also did a voltmeter test on the flame sensor and that was fine, but he cleaned it anyways and tested again. He kind of pointed out all troubleshooting steps that I have already done, and nothing seems out of order. It's all running now, will keep an eye on it. Perhaps the gas leak outside had something to do with it...doubtful but one can hope.

  8. #28
    Join Date
    Sep 2012
    Location
    Calgary, AB
    Posts
    1,636
    Rep Power
    85

    Default

    Originally posted by RX_EVOLV
    I had similar-ish problems a few years back with my Lennox furnace. I came home a few times to a &lt;10C house and found the furnace off. When I restart the furnace I would see the amber, but sometime it would restart back up, sometimes it would require quite a few restart for it to get going. When I do get it working it would work for at most a few weeks or just a few hours. I remember waking up at 6am to &lt;11C morning.
    I tried all the stuff recommended online like replace the filter, cleaning or replacing the flame sensor, turning down the humidity control, etc but no luck. I finally called a tech, half expecting to spend a fortune replacing a control board or something, and turns out one of the tube was clogged with debris, causing water to back up, and shutting off the furnace. He cleaned it out and the furnace been running good since. Took him all of 20 mins including diagnosis.

    The problem is not fully solved as it still happens once or twice a year, but when it does, I just undo that main hose, blow as hard as i could into it to unclog it, restart the furnace, and it would work flawlessly for another 8-10 months. Not ideal but beat buying another high efficiency furnace.

    I hope your problem is as simple as mine.

    Note: just read your last reply. My furnace fan would stay on the whole time too.
    Hmm, forgot about this. My PIL's furnace was cutting out too, I checked their intake and an animal decided to put a nest in there, also there was a kid's toy in there too. Took all that junk out, redid the metal cage around the end and it's been good since.

  9. #29
    Join Date
    Mar 2004
    Location
    Calgary AB
    My Ride
    2020 Subaru Forester Sport
    Posts
    2,969
    Rep Power
    41

    Default

    Originally posted by suntan
    Hmm, forgot about this. My PIL's furnace was cutting out too, I checked their intake and an animal decided to put a nest in there, also there was a kid's toy in there too. Took all that junk out, redid the metal cage around the end and it's been good since.
    Gonna check it out today. Didn't really think of this at all.

  10. #30
    Join Date
    Mar 2004
    Location
    Calgary AB
    My Ride
    2020 Subaru Forester Sport
    Posts
    2,969
    Rep Power
    41

    Default

    So near my furnace I have this



    This leads outside through a soft flexible hose thing, however, at the inlet area, it is very badly bent and I think very little air would make it through. The other inlet that leads to the return air in the furnace is open and has lots of cold air coming when I removed it to see inside.

    So the question is...is it possible that canister being blocked is preventing enough combustion air from coming in? I presumed it would draw on the air around it, and this isn't 100% necessary? Thoughts? It will require some crazy work to make breath.....can't believe they let this pass inspection back in the day.

  11. #31
    Join Date
    Jul 2013
    Location
    Calgary / Alberta
    Posts
    155
    Rep Power
    0

    Default

    Lets see picture of where it is bent. this is for combustion air for the furnace and hot water tank

  12. #32
    Join Date
    Jul 2013
    Location
    Calgary / Alberta
    Posts
    155
    Rep Power
    0

    Default

    Ya i assume you have a mid efficient furnace. Venting and pressure switch shouldnt be an issue considering when it starts to fault

  13. #33
    Join Date
    Mar 2004
    Location
    Calgary AB
    My Ride
    2020 Subaru Forester Sport
    Posts
    2,969
    Rep Power
    41

    Default

    Here are some pictures:

    Here is where the hose enters the house....the end of a stringer is in the way of proper flow, the hose is basically crushed at this point. Where the metal edge of the inlet pipe ends, to where the hose connects, there is like 1/4 inch of space and the hose is basically shut completely off.



    Here is is after I cut out a section of it (this is right at the end of a stringer that rests on a cross beam, so it serves no structural purpose at this point )



    Section that I cut out


    Can definitely see it's flowing now...the cold air coming out of it is noticeable, and is actually frosting up the end due to the cold weather outside....before there was nothing at all.



    Hope maybe it was the lack of fresh air for proper ignition? One can hope.

  14. #34
    Join Date
    Sep 2012
    Location
    Calgary, AB
    Posts
    1,636
    Rep Power
    85

    Default

    You probably have a dead mouse family in there.

  15. #35
    Join Date
    Sep 2002
    Location
    BoostLand
    My Ride
    something green
    Posts
    1,931
    Rep Power
    28

    Default

    Can you post a picture of your furnace? I just worked on a Lennox with similar symptoms.
    Too loud for Aspen

  16. #36
    Join Date
    Mar 2004
    Location
    Calgary AB
    My Ride
    2020 Subaru Forester Sport
    Posts
    2,969
    Rep Power
    41

    Default




  17. #37
    Join Date
    Apr 2009
    Location
    calgary
    My Ride
    acura TYPE A
    Posts
    398
    Rep Power
    15

    Default

    regardless of brand

    these units are not designed to be trouble free, they are designed to earn the HVAC industry a return each year most of it unethical, this why many people prefer not to "upgrade" their low efficiency, furance from the 1960s

    remove debris from all sensors
    make sure flame sensor is good
    make sure filter is clean
    make sure igniter is lighting up properly, if not replace or clean, (if igniter is not working manually light the flame durring the GAS on session) end if
    make sure inducer motor is ok and the vent is not clogged

    diag codes can help as well.

  18. #38
    Join Date
    Mar 2004
    Location
    Calgary AB
    My Ride
    2020 Subaru Forester Sport
    Posts
    2,969
    Rep Power
    41

    Default

    Well woke up this morning to a colder house again, so it wasn't the lack of fresh air, bummer.

    Starting to really think it's something with the gas valve. Going to do some more digging today. Curious what ur issue was Maxt.

  19. #39
    Join Date
    Jun 2003
    Location
    YWG
    Posts
    3,119
    Rep Power
    24

    Default

    What error codes are you getting (if any)?

    It might also be that your condensate drain is plugged.


  20. #40
    Join Date
    Sep 2012
    Location
    Calgary, AB
    Posts
    1,636
    Rep Power
    85

    Default

    Furnaces are remarkably simple devices, it's going to be your blower, the ignitor or the circuit board.

Page 2 of 4 FirstFirst 1 2 3 ... LastLast

Similar Threads

  1. Lennox Furnaces - Flame Sensor warning

    By Zero102 in forum Home and Garden
    Replies: 12
    Latest Threads: 11-08-2013, 11:40 AM
  2. Civic-Steering wheel won't unlock, key won't turn.

    By Seth1968 in forum Mechanical
    Replies: 0
    Latest Threads: 11-20-2010, 05:09 PM
  3. Furnace help!? Any Furnace techs on Beyond?

    By BMDUBS in forum Home and Garden
    Replies: 11
    Latest Threads: 12-13-2009, 12:59 PM
  4. Replies: 14
    Latest Threads: 11-21-2008, 06:05 PM
  5. Replies: 2
    Latest Threads: 09-16-2003, 11:18 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •