Results 1 to 22 of 22
  1. #1
    Join Date
    Oct 2003
    Location
    Rockwall Texas
    Posts
    4,517

    Default Burnt Thermostat Wiring

    Came across these burnt thermostat wires today. Has any one ever seen T-wiring burnt though as such. The wiring actually looked like it had been cut, but I can't figure out the burns on the wires.

    Any ideas?

    rick

    Similar Threads:
    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images
    Inspection Referral

  2. #2
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    26,186

    Default Re: Burnt Thermostat Wiring

    Rick,

    Any other evidence of a lightning strike?

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  3. #3
    Join Date
    Oct 2003
    Location
    Rockwall Texas
    Posts
    4,517

    Default Re: Burnt Thermostat Wiring

    Couldn't find any sign of anything like that.

    rick


  4. #4
    Join Date
    Mar 2007
    Location
    Santa Fe, NM
    Posts
    74

    Default Re: Burnt Thermostat Wiring

    A typical thermostat circuit uses a 24 VAC low voltage transformer supply. The thermostat / heating controller may require 100 milli-amps to over 1 Amp.

    So, if the wires were cut there would certainly be enough current to arc and melt / burn the insulating coating of the cable.

    The short-circuit (instantaneous) (in mili-seconds) current can be in hundreds and even thousands of amps. Thus causing a lot of sparking and smoking.

    Fuse protection of the T-stat voltage may or may not be implemented.

    In my former career I tested medical device hardware and software... sometimes we intentionally short-circuited power supplies and sometimes it was a surprise test... arc smoke and fire. Nothing like a resistor or a power SCR burning up to clear out a lab.


  5. #5
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    26,186

    Default Re: Burnt Thermostat Wiring

    Quote Originally Posted by Charles Smith View Post
    A typical thermostat circuit uses a 24 VAC low voltage transformer supply. The thermostat / heating controller may require 100 milli-amps to over 1 Amp.

    So, if the wires were cut there would certainly be enough current to arc and melt / burn the insulating coating of the cable.
    I've never seen one with enough power to spark that much, but could be.

    In my former career I tested medical device hardware and software... sometimes we intentionally short-circuited power supplies and sometimes it was a surprise test... arc smoke and fire. Nothing like a resistor or a power SCR burning up to clear out a lab.
    The problem is not the cut wires or burned up components, the problem is that you 'let the smoke out'. Any one around electricity knows that you can never 'let the smoke out', otherwise it will no longer work.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  6. #6
    Join Date
    Apr 2007
    Location
    gainesville fl
    Posts
    122

    Default Re: Burnt Thermostat Wiring

    looks like there might have been a plumber on site.


  7. #7
    Join Date
    Aug 2007
    Location
    Memphis TN.
    Posts
    4,311

    Default Re: Burnt Thermostat Wiring

    Quote Originally Posted by Charles Smith View Post

    So, if the wires were cut
    Charles,

    Good theory but the wires are Rounded Over from being Burned.

    It Might have Choked Artie But it ain't gone'a choke Stymie! Our Gang " The Pooch " (1932)
    Billy J. Stephens HI Service Memphis TN.

  8. #8
    Join Date
    Mar 2007
    Location
    Hudson, WI
    Posts
    645

    Default Re: Burnt Thermostat Wiring

    If that's thermostat, wire why do I only see one conductor?


  9. #9
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    26,186

    Default Re: Burnt Thermostat Wiring

    Quote Originally Posted by Michael Larson View Post
    If that's thermostat, wire why do I only see one conductor?
    The way it arced through.

    Look at the top section of the conductor and you will see the twists inside the outer sheath from the other conductors within the outer sheath.

    My only problem with it being thermostat wiring and being cut did that is the arc flash was so hot that it bubbled up the outer sheath. The only way I can imagine that happening is if someone mis-wired something and put 120 volts (or even 240 volts) on that, in which case a cut could do that.

    Maybe the transformer went bad, was mis-wired, who knows - I sure don't.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  10. #10
    Join Date
    Mar 2007
    Location
    Hudson, WI
    Posts
    645

    Default Re: Burnt Thermostat Wiring

    Quote Originally Posted by Jerry Peck View Post
    The way it arced through.

    Look at the top section of the conductor and you will see the twists inside the outer sheath from the other conductors within the outer sheath.

    My only problem with it being thermostat wiring and being cut did that is the arc flash was so hot that it bubbled up the outer sheath. The only way I can imagine that happening is if someone mis-wired something and put 120 volts (or even 240 volts) on that, in which case a cut could do that.

    Maybe the transformer went bad, was mis-wired, who knows - I sure don't.
    I did notice the twist.

    The copper looks awful shiny for having been exposed to an arc.


  11. #11
    James Duffin's Avatar
    James Duffin Guest

    Default Re: Burnt Thermostat Wiring

    The cable in the picture looks like the type of cable used by the power company when hooking up their load management equipment. I would be interested as where the cable terminated on each end.


  12. #12
    Michael Sierra's Avatar
    Michael Sierra Guest

    Default Re: Burnt Thermostat Wiring

    We had a similar situation happen to my inlaws, unfortunetly the issue caused a fie and the houes burnt down. It was a total loss but no one was hurt.

    In there case a contractor had remodled the kitchen and wired a thermostat incorrectly. This caused the unit to alway be on, it was a local under the counter heater. The constant heat caused the wire to over heat and burn. The wire looked the same at the edges but with out the cut


  13. #13
    Join Date
    Aug 2017
    Location
    Texas
    Posts
    6

    Default Re: Burnt Thermostat Wiring

    Quote Originally Posted by Rick Hurst View Post
    Came across these burnt thermostat wires today. Has any one ever seen T-wiring burnt though as such. The wiring actually looked like it had been cut, but I can't figure out the burns on the wires.

    Any ideas?

    rick
    hello I have something a little closer, and also found a board Level Burn that caused my Thermostat to burn the wires. See here these 2 pics will show what happened and this is why, the Removal of a Common wire in thermostats, yes this is why as a Test Tech I have found why this happens.

    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images

  14. #14
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    26,186

    Default Re: Burnt Thermostat Wiring

    Curious as to why you came here, seemingly to ask a question, only to tell us how much more experience and knowledge you have?

    Seems to me that the "question" was made up as you already knew the answer.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  15. #15
    Join Date
    Mar 2007
    Location
    Santa Rosa, CA
    Posts
    2,464

    Default Re: Burnt Thermostat Wiring

    Off topic...

    I noticed Rick Hurst started this thread 10 years ago. He hasn't been heard from in quite a while. Anyone have any news on him?

    Department of Redundancy Department
    http://www.FullCircleInspect.com/

  16. #16
    Join Date
    Mar 2007
    Location
    Plano, Texas
    Posts
    145

    Default Re: Burnt Thermostat Wiring

    Quote Originally Posted by Gunnar Alquist View Post
    Off topic...

    I noticed Rick Hurst started this thread 10 years ago. He hasn't been heard from in quite a while. Anyone have any news on him?
    He still has an active license with TREC until 2018. Since our licenses are good for 2 years he renewed just last year. I did a home about a year ago that he had inspected for the seller. I think he just stopped using the forum.


  17. #17
    Join Date
    Dec 2008
    Location
    Maryland
    Posts
    2,763

    Default Re: Burnt Thermostat Wiring

    Quote Originally Posted by Jennifer Case View Post
    hello I have something a little closer, and also found a board Level Burn that caused my Thermostat to burn the wires. See here these 2 pics will show what happened and this is why, the Removal of a Common wire in thermostats, yes this is why as a Test Tech I have found why this happens.
    Quote Originally Posted by Jerry Peck View Post
    Curious as to why you came here, seemingly to ask a question, only to tell us how much more experience and knowledge you have?

    Seems to me that the "question" was made up as you already knew the answer.

    Jerry, have to agree with the exception that I do not think Jennifer really has the knowledge to offer an opinion. She states that "as a Test Tech I have found why this happens." though she opened a thread questioning why her AC was not working and showing a picture from a old thread. Also obscuring the the burned board and notations. OR have I missed something.

    There is a fried board. Exactly what fried and why may be the underlying question. The board burnt not the wires.

    Then there is the question of "craftsmanship or design" and not knowing the difference.


  18. #18
    Join Date
    Mar 2007
    Location
    New Mexico
    Posts
    1,257

    Default Re: Burnt Thermostat Wiring

    I really wish we would close threads after 30 days, or some set period of time with no activity.

    Jim Robinson
    New Mexico, USA

  19. #19
    Join Date
    Mar 2007
    Location
    Santa Rosa, CA
    Posts
    2,464

    Default Re: Burnt Thermostat Wiring

    Quote Originally Posted by Gary Burnett View Post
    He still has an active license with TREC until 2018. Since our licenses are good for 2 years he renewed just last year. I did a home about a year ago that he had inspected for the seller. I think he just stopped using the forum.
    Hi Gary,

    Good to know, thanks. If you run into him (unlikely, I realize), let him know he is missed and HG is gone).

    Department of Redundancy Department
    http://www.FullCircleInspect.com/

  20. #20
    Join Date
    Mar 2013
    Location
    Washington, DC
    Posts
    3

    Default Re: Burnt Thermostat Wiring

    Quote Originally Posted by Gunnar Alquist View Post
    Hi Gary,

    Good to know, thanks. If you run into him (unlikely, I realize), let him know he is missed and HG is gone).

    What happen to HG Watson? Did anyone ever unmask his identity? The thread on his identity never reached a conclusion.


  21. #21
    Join Date
    Dec 2008
    Location
    Maryland
    Posts
    2,763

    Default Re: Burnt Thermostat Wiring

    Think Watson copped an attitude for being reprimanded and drifted off. . Or his Heath went South and his keyboard was taken away to keep his BP down.


  22. #22
    Join Date
    Mar 2007
    Location
    Santa Rosa, CA
    Posts
    2,464

    Default Re: Burnt Thermostat Wiring

    Quote Originally Posted by cliff kornegay View Post
    What happen to HG Watson? Did anyone ever unmask his identity? The thread on his identity never reached a conclusion.
    Quote Originally Posted by Garry Sorrells View Post
    Think Watson copped an attitude for being reprimanded and drifted off. . Or his Heath went South and his keyboard was taken away to keep his BP down.
    According to his IN profile, he last looked in on June of this year but his last post was in 2014.

    Department of Redundancy Department
    http://www.FullCircleInspect.com/

Bookmarks

Posting Permissions

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