Page 1 of 3 123 LastLast
Results 1 to 13 of 32
  1. #1
    Join Date
    Nov 2019
    Location
    Kansas City, MO
    Posts
    3
    Post Likes

    Confused Trane YCH300B3 Rooftop Ignition Problem

    Have trouble with a Trane rooftop ignition. Replaced the surface igniter. Combustion blower comes on, igniter comes on but no ignition. I can smell gas through exhaust ports. Any ideas.

    Thanks,
    Big D

  2. #2
    Join Date
    Feb 2017
    Location
    New York
    Posts
    1,661
    Post Likes
    Have you checked the gas pressure?

    Sent from my SM-G935U using Tapatalk
    -----Stop, step back, relax and have another go at it.-----

  3. #3
    Join Date
    May 2014
    Location
    Bay Area California
    Posts
    25,720
    Post Likes
    How did you verify the igniter is coming on?

    Also, if this is a negative pressure gas valve, be very careful if you make any adjustments at all.
    I do a triple evac with nitro to remove non condensables.

  4. #4
    Join Date
    Nov 2019
    Location
    Kansas City, MO
    Posts
    3
    Post Likes
    Thread Starter
    I've got power to the igniter and it's hot to the touch. I haven't checked the gas pressure. I'll check it tomorrow.

  5. #5
    Join Date
    May 2014
    Location
    Bay Area California
    Posts
    25,720
    Post Likes
    Typically we check for current. Is it red hot, without touching it (LOL) ?

    Pretty sure the YCH has a negative pressure gas valve. Put your manometer on it and watch what happens, don't touch or adjust anything until you watch it through a sequence. First time I checked pressure on a negative pressure gas valve, even knowing it was a negative pressure gas valve, it did not act like I thought it would act.


    Quote Originally Posted by Big D 60 View Post
    I've got power to the igniter and it's hot to the touch. I haven't checked the gas pressure. I'll check it tomorrow.
    I do a triple evac with nitro to remove non condensables.

  6. #6
    Join Date
    Nov 2019
    Location
    Kansas City, MO
    Posts
    3
    Post Likes
    Thread Starter
    Yeah, I just touched the ceramic base, while it was in the slot. Lol. I'll take my manometer tomorrow.

    Thanks!

  7. #7
    Join Date
    May 2014
    Location
    Bay Area California
    Posts
    25,720
    Post Likes
    If memory serves, you're looking for minus 0.04" water column of gas pressure at the outlet of the gas valve once it actually opens. It's something like minus 4" after a call for heat, but before it opens. It'll trip you out until you're used to it.
    I do a triple evac with nitro to remove non condensables.

  8. #8
    Join Date
    May 2014
    Location
    Bay Area California
    Posts
    25,720
    Post Likes
    Stop by more often. Interact, then apply for pro membership after you have 15 meaningful posts. There's a bunch of stuff in the pro section that I'm guessing you'll enjoy reading. It'll make you a better tech. I'm old, and still learning from this site . . . !


    Quote Originally Posted by Big D 60 View Post
    Yeah, I just touched the ceramic base, while it was in the slot. Lol. I'll take my manometer tomorrow.

    Thanks!
    I do a triple evac with nitro to remove non condensables.

  9. #9
    Join Date
    Sep 2007
    Location
    edmonds wa
    Posts
    4,433
    Post Likes
    I would also add to verify heat exchanger is good, gas pressure check as said above, and put a amp clamp on the HSI while energized, you can have a small crack that will get warm but not ignite. If the igniter is good, after a couple cycles i would expect burnt fingers grabbing the porcelain body.
    UA Local 32 retired as of Jan 2020

  10. #10
    Join Date
    Jan 2010
    Posts
    18,573
    Post Likes
    Ignitor should be no more then 100 ohm's.

  11. #11
    Join Date
    May 2014
    Location
    Bay Area California
    Posts
    25,720
    Post Likes
    So . . . When it is red hot, I should grab it tightly. Is that what ohm's mean?


    Quote Originally Posted by VTP99 View Post
    Ignitor should be no more then 100 ohm's.
    I do a triple evac with nitro to remove non condensables.

  12. #12
    Join Date
    Nov 2006
    Location
    Southeastern Pa
    Posts
    32,121
    Post Likes
    I carry Trane Kit3033 on the truck for just such situations.
    [Avatar photo from a Florida training accident. Everyone walked away.]
    2 Tim 3:16-17

    RSES CMS, HVAC Electrical Specialist
    Member, IAEI

    AOP Forum Rules:







  13. #13
    Join Date
    Nov 2011
    Location
    East Side
    Posts
    7,178
    Post Likes
    Ignitor should pull more than 4 amps I believe....been awhile. I guess I need to get back into heat mode!

Page 1 of 3 123 LastLast

Posting Permissions

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