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Old and discontinued Mizer Johnson Control M35BA-1 Damper control replacement

ddcha
ddcha Member Posts: 21
Hi everyone,

I have a 20 year old damper for my furnace and the motor seems to be worn out. not strong enough to open and close the damper. If I give it some help, it can finish the rotation, but seems weak. I need to replace the damper control but this is no longer manufactured. I know that there is an M35BE-1 replacement, but even that is discontinued. Is there a replacement plug and play piece I can use to replace the damper control unit? Please advise.

Comments

  • HVACNUT
    HVACNUT Member Posts: 3,945
    Can you post pics of the damper, damper motor, and zone board?

    The motor is not strong enough?
    Is it power close/power open, or power close/spring open?

    How difficult would it be to replace the whole damper, complete with new motor?
    It might be easier.

    When ordering a zone damper, the motor mounts on the first dimension.
    24 x 18. Motor on the 24
    18 x 24. Motor on the 18
  • ddcha
    ddcha Member Posts: 21
    Thanks for your response. So when a cycle starts, the motor turns the gears but not strong enough to turn the damper. I tried to free up the damper a bit to make it turn open/close more easily. It turns clockwise. That didn’t work unfortunately. Here are some pics.
  • ddcha
    ddcha Member Posts: 21
    One more with damper control taken off
  • SuperTech
    SuperTech Member Posts: 1,650
    Field controls makes a flue damper that should work as a replacement. What model aquastat do you have?
  • ddcha
    ddcha Member Posts: 21
    Aquastat L8148E
  • ddcha
    ddcha Member Posts: 21
    Damper motor picture
  • SuperTech
    SuperTech Member Posts: 1,650
    The field controls damper should be able to plug right into that aquastat.
  • HVACNUT
    HVACNUT Member Posts: 3,945
    Sorry.🙄
    I thought we were talking about zone dampers. I thought I Googled it.

    Is it locked closed right now?
    Can you manually open it?
    Is there a manual lock open switch on it somewhere so it can be used for now?

    Agree with @SuperTech .The Molex plug should be typical.
  • ddcha
    ddcha Member Posts: 21
    edited March 2020
    Thank you both. I screwed off the damper control and left the damper in open position. This way, the control will cycle and the furnace will fire. Can you tell me which field control product to purchase? I looked at this Field Control GVD Motor Assembly: https://www.supplyhouse.com/Field-Controls-70009800-GVD-Vent-Damper-Motor-Assembly-Metal-Base

    However, from the pictures, the back side doesn't seem to match because the part that connects to the damper is not centered.
  • ddcha
    ddcha Member Posts: 21
    Off center like this:
  • ddcha
    ddcha Member Posts: 21
  • HVACNUT
    HVACNUT Member Posts: 3,945
    edited March 2020
    Just order the whole GVD-?
    The number designates the flue pipe size.
    15 minute swap.
    Don't set any screws that will interfere with the damper.
  • ddcha
    ddcha Member Posts: 21
    Dumb question but how do I measure the size? Im assuming I need the diameter
  • Steamhead
    Steamhead Member Posts: 14,564
    ddcha said:

    Dumb question but how do I measure the size? Im assuming I need the diameter

    Just use a tape measure- hold one end parallel with one side of the smoke pipe and see where the other end measures out to.
    All Steamed Up, Inc.
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
  • HVACNUT
    HVACNUT Member Posts: 3,945
    Or a flat ruler.
    It also might be stamped on the piping. Ex. 6 in, 26 gauge.

    You can get a string and do the whole pi x r2 thing too.
  • ddcha
    ddcha Member Posts: 21
    Thanks. Wish me luck.
  • ddcha
    ddcha Member Posts: 21
    I used the string and calculate 7.32inches. 23 inch diameter divided by 3.14 = 7.32. What now.
  • ddcha
    ddcha Member Posts: 21
    Remeasured. 7.12 diameter by my calc. Close enough.
  • HVACNUT
    HVACNUT Member Posts: 3,945
    edited March 2020
    7" diameter

    GVD-7
    Easy Peezy
  • ddcha
    ddcha Member Posts: 21
    Ordered the GVD-7 and the harness kit. Thanks for all your help folks. Stay tuned.
  • ddcha
    ddcha Member Posts: 21
    edited April 2020
    So I installed the GVD-7 with the harness kit. I thought it was going to work. When I plugged it in, the damper moved to the close position (evidence that I'm getting power right?). The problem I have now is that it won't open when I raise the thermostat. Please help.
  • HVACNUT
    HVACNUT Member Posts: 3,945
    Was the system working right up until you replaced the damper? Besides the reason it needed to be replaced.

    No obstruction? The damper is able to pivot freely?

    Do you have an electrical meter?
  • ddcha
    ddcha Member Posts: 21
    No obstruction. It was working fine before. I just left it open temporarily until I could get this replacement. The harness is tight and all connections appear correct.
  • ddcha
    ddcha Member Posts: 21
    I took off the new damper and put the old one back on. Left the damper in open position and took the control off the damper so that the motor “thinks” it is opening and closing the damper. It’s running again. Not sure if it’s a compatibility issue with my aquastat.
  • ddcha
    ddcha Member Posts: 21
    edited April 2020
    One more thing I did not mention before is that I have Two furnaces. When I have the old damper controls installed, both furnaces run when the system calls for heat. When I installed the new Field Controls on the one furnace on the left, only the right side would function. Is it because I need the same brand on both sides? Please help.
  • ddcha
    ddcha Member Posts: 21
  • ddcha
    ddcha Member Posts: 21
    Bump please
  • ddcha
    ddcha Member Posts: 21
    no one?
  • pecmsg
    pecmsg Member Posts: 2,064
    edited April 2020
    Please tell me the Safety switch is still hooked up! If that damper begins to close will the boiler shut down?
  • ddcha
    ddcha Member Posts: 21
    Thanks for the concern. No it isn't hooked up, but I made sure it doesn't close back up.
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