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In this video Eric Mele rewires DC fan controls to prevent some issues in market refrigeration.
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This is eric with calo services in hvac school and today we're going to be rewiring, this refrigeration condenser. This is a close-up of the schematic. Let's get a shot of the condenser, so people know we're working on just a basic condenser, only no compressor, but the issue we're having here. If you look at how this is wired, your 1 to 10 volt dc signal comes out to your first motor and then the rest of the motors are wired in series.

So it relies on this first motor working for the rest of the motors to work properly. Now there is an alarm relay in the motor and if the motor shuts itself off it should switch this relay and send the signal to the subsequent motors. But the problem is: if this motor loses power, it will not. So if motor 2 loses power, it takes out all four of these motors and if it's a bigger condenser, you just lose more motors, you know same deal.

Motor four will take out six and eight. It's just not a good situation for market refrigeration. So what we're gon na do today is we're gon na wire, all these motors in parallel right now, they're wired in series, so we're going to get rid of this output wire and we already have blue wired in parallel to our alarm relay which blue and red Coming from this terminal board, right here are the same thing, so we're going to move the blue wire to the 1 to 10 volt terminal on all these motors, except the last motor, where we don't have a blue wire, we're actually going to run a new wire From the terminal block to the motor, because that motor is actually closest to the terminal block, so it's not a big deal so we'll get rid of we'll disconnect all the red wires, save them off inside the motor. In case it ever needs to go back to the factory configuration and we're just going to swap the blues and run an additional wire.

So what we're going to do is remove this red wire switch it with this blue wire and then we're going to connect it up to the terminal block here and here for our motors that we're connecting these these last two so that red wire is going to Get abandoned in the box and taped off and shoved in the bottom. It's going to get put down here in the low voltage side. Now, with this fan and the other middle fans we're going to move this blue wire here to this here and remove these two red wires, so this relay is normally closed and it's an alarm relay. So when the motor goes into it knows it failed and it still has power.

Then it's going to pass the signal to the next motor down the line, but in this case that's not going to happen for all the middle motors. What i'm going to do here is going to be typical again we're going to remove these two red wires and we're going to put this one here. So here's what it looks like done. We got blue over here.

We've got our two reds taped off and jammed down. So that's going to be the middle motors. Now let me show you this is nearest the electrical end. We have our wire that we ran right there with the blue tape mark and we have our red wire in the bottom taped off all right.

So this is the lead motor. So we really don't have to switch anything here, but i'm just going to do it for continuity of everything being the same, because this blue and red wire are identical here. If you look at the schematic, but i'm going to put this blue wire here and take the reds off just like we've done at the other motors now, you see this is a newer style motor than the ones we looked at, but it's the right replacement motor For this, the new ones will look a little different, and here is the lead. Motor rewired, like i said, really, doesn't make a difference on this one, but just for everything to be matching so everything's wired to blue in parallel, so they're all going to react.

The same and if any motor fails, it's not going to take any other motors out of the circuit supposed to be zero percent chance of rain today, but good thing, these aren't sensitive powered, electronics right. This is our final wiring we're not using red anymore. So those are all disconnected in our motors - and it's disconnected here so there's no potential on red, we're using blue and here's the blues that we added here and here to go to our closest two motors, which are these two here so everything's running direct acting parallel. Now is our current configuration before it was direct acting series, so as long as this board stays working, the motors should stay working thanks for watching our video.

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17 thoughts on “Rewiring market condenser fans”
  1. Avataaar/Circle Created with python_avatars Juan Todolí says:

    I read this, tell me if I'm wrong: If some KL2 kicks on, then next motor get voltage not by YEL throughout NC and COM, but by BLU wire (always live) throughout NO and COM.

  2. Avataaar/Circle Created with python_avatars porkeater55 says:

    A lot of nice pics of your hand. Hoped to learn something from this, all I saw was screwdriver and hand shots.

  3. Avataaar/Circle Created with python_avatars Dwayne Doxilly says:

    Great information

  4. Avataaar/Circle Created with python_avatars Rene Ozuna says:

    After doing this and once you have another motor fails the one that is down will spin backwards and not allow properly right?

  5. Avataaar/Circle Created with python_avatars RJ_Make says:

    Very Nice. Eric's channel had the raw version 🙂 This one is MUCH better, and now I understand.. Thank You!

  6. Avataaar/Circle Created with python_avatars Jim Spier says:

    It looks by the original schematic the intended design was to have each motor take the PWM signal and regenerate it to the next motor via the signal output. This would prevent signal degradation of the low voltage PWM wire when connected in parallel with many motors. Have you seen many failures with these motors?? I would have thought the high voltage to all the motors would be fed from a common fused circuit, in which, not just one would loose power.

  7. Avataaar/Circle Created with python_avatars Mohamed el agheb Tall says:

    Thanks everything to do for us!
    I would be to your side like an apprentice

  8. Avataaar/Circle Created with python_avatars ClickyMcbuttons says:

    Jandy was here.

  9. Avataaar/Circle Created with python_avatars Gostevo79 says:

    One of the worse shot videos I’ve seen from this channel.

  10. Avataaar/Circle Created with python_avatars RV10flyer says:

    So, they are basically wired like my 20,000 W solar system in series. If one panel goes out and knocks the other seven now. I can’t wire them in parallel because the voltage would go from 320 V to40 V DC. I don’t work on commercial refrigeration, but thanks for all of your videos.

  11. Avataaar/Circle Created with python_avatars Mr Green says:

    Woah I thought you guys were only residential. Is this a crac unit? Service area Ottawa??

  12. Avataaar/Circle Created with python_avatars Jammin Wrenches says:

    Engineers: placing the motors in series will make it completely modular and simplify design. We will add an alarm relay to guard against failure.
    Techs: but EVERYTHING can break so let's wire it passive redundant.

  13. Avataaar/Circle Created with python_avatars ohmycrotch says:

    where can I buy these condenser fans? i have trouble finding them.

  14. Avataaar/Circle Created with python_avatars Richard Kile says:

    Great video but I agree with the showing the wiring a little bit longer to get a better understanding as another person said. Thx for sharing. Are you in Kanata ?

  15. Avataaar/Circle Created with python_avatars RJParker says:

    So how was this change documented so that the next guy who sees this cold is not cussing the guy before him? Redlines on the schematic?

  16. Avataaar/Circle Created with python_avatars Brian Carlisi says:

    Good stuff but you should keep the camera steady and on the wiring a little longer. Constant movement made this hard to watch. Your a great tech and am learning lots from you, Eric. Thank you

  17. Avataaar/Circle Created with python_avatars Jeff B says:

    Good stuff

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