Seal Dry Mount Press Overheating

Discussion in 'Miscellaneous Equipment' started by Alex Hawley, Oct 12, 2008.

  1. Alex Hawley

    Alex Hawley Member

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    I recently bought a Seal 160M dry mount press on that auction site. The press is relatively new but the darn thing overheats. I've replace the thermostat with a new one but it hasn't fixed the problem. The amber heating indicator light goes out like it should but the the temperature will climb right up past the thermostat setting and keep on going until I turn the power off.

    Anyone else experience this problem? Any ideas on how to fix it?
     
  2. Bob-D659

    Bob-D659 Member

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    Sounds like an internal short or it's been mis-wired. Make sure the thermostat breaks the circuit to the heating element, not just the one to the indicator lamp.
     
  3. paul ron

    paul ron Member

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    I'm not sure, but is there another sensor in the thing?
     
  4. Shawn Dougherty

    Shawn Dougherty Member

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    Alex, I'm have the SAME problem with a 210m I purchased. I even bought a new thermostat and still have the same issue. The problem is either that it's mis-wired or one of the wires is screwed up. I'm going to check out how my buddies press is hooked up. If it's that same as mine then I'll get my hands on a continuity tester and see which wire is causing the problem. The machine is so simple I don't think there is another possibility. I hope to do this within the next week. I'll let you know what happens. All the best. Shawn
     
  5. DWThomas

    DWThomas Subscriber

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    (Speculation here, I don't own one...)

    Do these presses perchance use a relay between the thermostat and the heating elements? If so, the relay might be sticking, contacts welded by arcing or the like.

    (Well, there's no charge for this "advice.")

    DaveT
     
  6. Alex Hawley

    Alex Hawley Member

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    AHA! So its not just me and the press I have. That's really good to know Shawn and thanks for posting.

    Dave, there's no relay in the circuit. I took the old thermostat apart today (very easy to do) and its a simple bimetalic strip device.

    I think it may be the calibration of the thermostat itself. There's a calibration adjustment screw at the bottom of the knob stem. Had to borrow a screwdriver to get to it because none of mine were long and slender enough to reach the screw. Going to try adjusting the calibration tonight. Will post the results.
     
    Last edited by a moderator: Oct 16, 2008
  7. nc5p

    nc5p Member

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    Mine is the same way, so I put a big Variac transformer in front of it. I set it to 35% and it stays at the right temperature for my paper combination. One of these days I'll probably fix it properly.
     
  8. Alex Hawley

    Alex Hawley Member

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    nc5p, where does one get Variac transformers these days?
     
  9. Alex Hawley

    Alex Hawley Member

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    Tried calibrating the thermostat. No Joy. That means the heater has to wired in parallel with the thermostat instead of in series. Not easy to track down but necessary.
     
  10. Shawn Dougherty

    Shawn Dougherty Member

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    Alex, sorry for getting back so late. It turned out my problem was exactly what you just described, wired in parallel in stead of series. I have the wiring schematics, if you need them PM me. I ended up taking the press and schematics to a local electrician, who aside from melting my 100 pressure pad, was able to fix it. Mounted some prints last night and everything is working great. Good luck. Shawn
     
  11. Alex Hawley

    Alex Hawley Member

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    Thanks Shawn. PM on its way. I've been using the press by controlling it with the on/off switch. That's OK up to a point.