Results 1 to 14 of 14

Thread: Lennox LGA240 M1 to M2 board

  1. #1
    Join Date
    Nov 2013
    Location
    Okc, Oklahoma
    Posts
    45
    Post Likes

    Lennox LGA240 M1 to M2 board

    Anyone ever have to replace the original A55 board with the new prodigy board and any luck?

    Currently no A55 boards produced or in production till after the 12th

  2. #2
    Join Date
    Apr 2010
    Location
    Texas
    Posts
    699
    Post Likes
    That's no small task. Theoretically it should work, but you'd have to rework the entire harness at the board and extend a lot of the wires that only reach exactly where they need to. Cut off all the plugs and crimp QC connectors onto every wire. Between trying to identify each connection, modifying the harness, configuring a new M3 to believe that it came from the factory this way, then testing of every single unit function, I'd think you'd be better off waiting.

    That said, what's wrong with the one you have? I worked at Lennox NAS for 4 years and worked on hundreds of L-Series and Energence units, and I think I only replaced 1 M2 board in all that time, that got smoked when a CFM relay caught on fire, melted, burnt the wiring until it sagged into itself, and then sent 480 through the control wiring.


  3. Likes mpenney liked this post.
  4. #3
    Join Date
    May 2004
    Location
    Salt Lake City/Tooele
    Posts
    6,064
    Post Likes
    I responded to the PM you sent me.

  5. Likes mpenney liked this post.
  6. #4
    Join Date
    Nov 2006
    Location
    Southeastern Pa
    Posts
    32,365
    Post Likes
    I would make some temporary wiring, but I would not install a prodigy in place of an IMC. Too much work, especially if you are using the thermostat inputs. A few jumpers and you are done.
    [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:







  7. #5
    Join Date
    Nov 2013
    Location
    Okc, Oklahoma
    Posts
    45
    Post Likes
    Thread Starter
    It won’t send a call for heat in test, ddc or when changed to 24v

  8. #6
    Join Date
    Nov 2013
    Location
    Okc, Oklahoma
    Posts
    45
    Post Likes
    Thread Starter
    I t won’t send a call for heat in test, ddc or when changed to 24v.
    I went back to see if I overlooked something. 15mins (felt like 15mins) later it finally comes on for test after realistically 10mins

  9. #7
    Join Date
    May 2004
    Location
    Salt Lake City/Tooele
    Posts
    6,064
    Post Likes
    What faults, if any have been recently saved?

    Other than yourself recently has anyone to your knowledge worked on this unit? Sometimes someone meaning well, plays with the ECTO parameters and unbeknownst to them create some unintended issues, that you are now dealing with.

    How is this particular RTU controlled? Local thermostat, zone sensor, BAS? If by BAS is it through a Lennox L-Connect network, or others?

    What accessories are on the unit? Economizer, Power Exhaust, Modulating Gas, Humiditrol, etc.

    What is the FULL model number?

    There should also be a "Build As" sticker on the rooftop unit is should list all the options and accessories that the RTU was shipped with out of the factory. May want to take a photo of that helps getting an idea what all that RTU was designed to handle.

  10. #8
    Join Date
    Nov 2013
    Location
    Okc, Oklahoma
    Posts
    45
    Post Likes
    Thread Starter
    It was being controlled with a zone sensor. This is the last unit they want converted to a regular stat

    LGA240H4bs6g
    5608f05411





    Quote Originally Posted by slctech View Post
    What faults, if any have been recently saved?

    Other than yourself recently has anyone to your knowledge worked on this unit? Sometimes someone meaning well, plays with the ECTO parameters and unbeknownst to them create some unintended issues, that you are now dealing with.

    How is this particular RTU controlled? Local thermostat, zone sensor, BAS? If by BAS is it through a Lennox L-Connect network, or others?

    What accessories are on the unit? Economizer, Power Exhaust, Modulating Gas, Humiditrol, etc.

    What is the FULL model number?

    There should also be a "Build As" sticker on the rooftop unit is should list all the options and accessories that the RTU was shipped with out of the factory. May want to take a photo of that helps getting an idea what all that RTU was designed to handle.

  11. #9
    Join Date
    May 2004
    Location
    Salt Lake City/Tooele
    Posts
    6,064
    Post Likes
    Okay,

    Did you change the internal ECTO parameter for system control from looking for a zone sensor and failing to a thermostat, to running off a thermostat and failing to a zone sensor?

    You just can not hook up a conventional thermostat to one of these units, once they are set-up to run off of a zone sensor. You may already know this and made the necessary change in the ECTO parameters? Double Check you did this correctly.

    If not, that is your issue, board is looking at the zone sensor and since there is no longer one installed it will not do anything, as for the delay during TEST mode I am not sure what went on there.

    You will need to check that ECTO parameter and make sure it is set for "0" zero.

    See attachment below for that particular ECTO parameter
    Attached Images Attached Images  

  12. #10
    Join Date
    Nov 2013
    Location
    Okc, Oklahoma
    Posts
    45
    Post Likes
    Thread Starter
    Yes. I changed 601 to 0.
    The maintenance guys I do t think would of messed with the parameters 😆 hopefully

    I did find the burnt spot on the board. I have. I idea why it acted like that

  13. #11
    Join Date
    Nov 2013
    Location
    Okc, Oklahoma
    Posts
    45
    Post Likes
    Thread Starter
    It never had any faults either 😳


    Quote Originally Posted by slctech View Post
    Okay,

    Did you change the internal ECTO parameter for system control from looking for a zone sensor and failing to a thermostat, to running off a thermostat and failing to a zone sensor?

    You just can not hook up a conventional thermostat to one of these units, once they are set-up to run off of a zone sensor. You may already know this and made the necessary change in the ECTO parameters? Double Check you did this correctly.

    If not, that is your issue, board is looking at the zone sensor and since there is no longer one installed it will not do anything, as for the delay during TEST mode I am not sure what went on there.

    You will need to check that ECTO parameter and make sure it is set for "0" zero.

    See attachment below for that particular ECTO parameter

  14. #12
    Join Date
    May 2004
    Location
    Salt Lake City/Tooele
    Posts
    6,064
    Post Likes
    Looking like a board then.

  15. #13
    Join Date
    Nov 2013
    Location
    Okc, Oklahoma
    Posts
    45
    Post Likes
    Thread Starter
    Oh yaaaaaa.
    I got it changed out and she’s rocking and rolling now. I did find an online parts house that had the board and it was ordered Monday and delivered yesterday before noon. I was kinda impressed

    Thanks for all your help slctech

  16. Likes CHAINIK, slctech liked this post.
  17. #14
    Join Date
    May 2004
    Location
    Salt Lake City/Tooele
    Posts
    6,064
    Post Likes
    My pleasure buddy.

Posting Permissions

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