Troubleshoot challenge!Bad transformer?
Page 1 of 3 123 LastLast
Results 1 to 13 of 28
  1. #1
    Join Date
    Mar 2005
    Posts
    65
    Service call.Furnace not working.Troubleshooted down to transformer.Checked voltage in.Verified 120 v. going in by clamping vom to black and to ground.No power out on 24v side.Replaced transformer 3 times, same result.Solutions from all welcome.Bad shipment of transformers or what?

  2. #2
    Join Date
    Mar 2004
    Location
    Grottoes VA
    Posts
    5,856
    You better recheck your meter or where your reading from. Ohm out the x-frmr.
    Karst means cave. So, I search for caves.

  3. #3
    Join Date
    Mar 2005
    Posts
    65
    Ohmed out all three transformers.All good.Used two different meters-same results.Read from black to furnace body to ground and complete circuit.Same results.

  4. #4
    try checking volts to netural instead of ground. is this a multi volt trans?

  5. #5
    Join Date
    Jan 2004
    Posts
    157
    did u check for neutral on incomming power

  6. #6
    Join Date
    Dec 2004
    Location
    Grand Rapids, MI
    Posts
    604
    Better install an inline fuse on new transformer while working on bad transformer jobs.

  7. #7
    Join Date
    Nov 2001
    Location
    east kansas
    Posts
    8,024
    Don't check nothing to ground. Always check between L1 and L2.

    You should be able to check L1 and L2 right at the x-former.

    If you have potental on L1 and L2 then do you have potental at R & C at the x-former.

    You might want to ohm out those "bad" transformers. If they are blown, put a fuse in the low voltage side.

    So how much training have you compleated?

  8. #8
    Join Date
    Mar 2005
    Posts
    65
    You got me!I'm a student at a trade school and I was just wondering why three fellow students and TWO instructors could'nt figure that one out without replacing even one transformer.I had them go to neutral and they got 40v instead of 120v.I looked in ceiling and the neutral came loose from a pig-tail in juncture box.

  9. #9
    Join Date
    Mar 2004
    Location
    Grottoes VA
    Posts
    5,856
    I bet he is using a 230V x-frmr on a 110V circuit.
    Karst means cave. So, I search for caves.

  10. #10
    Join Date
    Mar 2005
    Posts
    65
    I've been going about a year, and if you think that story is scary- I have more even worse.

  11. #11
    Come back and see us after your first week in the field there killer... I would seriously re-evaluate any school that has instructors who would teach checking for voltage in this manner.

  12. #12
    Join Date
    Mar 2005
    Posts
    65
    I just had an instructor proudly show me an electric furnace he said only used contacters and no sequencers.I asked him to show me it and he said here it is!See!No sequencers!And straight ahead at eye-ball level were the heating coils with wires going directly - five inches away- to two sequencers. I asked him one more time if he saw any sequencers, and he said no!

  13. #13
    Join Date
    Mar 2005
    Posts
    65
    Is there any way the industry can get involved directly with these trade schools? After all, these graduates are going to wind up in the field working on their equipment, so wouldn't it make sense to start leaning on trade schools by lending endorsment to good ones and setting requirements?

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
  •  
Comfortech Show Promo Image

Related Forums

Plumbing Talks | Contractor Magazine
Forums | Electrical Construction & Maintenance (EC&M) Magazine
Comfortech365 Virtual Event