WaterFurnace W2W start up issue

Discussion in 'General Discussions' started by DaveO, Nov 13, 2018.

  1. DaveO

    DaveO New Member

    I have a Waterfurnace W2W heat pump and this a.m. I noticed it was having trouble starting up. It seems the compressor is kicking on for a few seconds and then shuts down. I checked the capacitor with an ohm meter and that shows to be working. The load side circulator pump from the buffer is working. I still need to verify the pumps in the flow center are working from the closed loop field, but I did replace the fuses for them inside the ht pump.

    Any advice would be greatly appreciated.

  2. DaveO

    DaveO New Member

    Well after checking the compressor and capacitor again last night with the multi meter, I still had a thought that something was going on with the flow center and the source (field) side. So I closed the isolating values to the field and let off the bleed screw of the supply circulator pump, sure enough air escaped that must have been trapped in the heat pumps source side coaxial heat exchanger. I closed the bleed screw and turned the breaker back on and the heat pump is now purring like a kitten!
    I'm not sure if this air lock is related to having the system shut down over the summer months as I just turned my system on the beginning of November?

    Thanks for reading!
  3. ChrisJ

    ChrisJ Active Member Forum Leader

    Welcome. Glad you resolved the issue.
  4. DaveO

    DaveO New Member

    Well it seems the air lock was only part of the problem with my heat pump. Now the circulation pump from the starts up to check the temp of the buffer tank and after a few minutes it shuts down and the compressor doesn't start up at all now. Also the digital read out on the heat pump that shows the temp goes black but it doesn't kick the fuse off in the elec. panel. Could it be that all along I have been having a leak in the Freon causing these symptoms and now have run out? Any thoughts are welcome.
  5. nc73

    nc73 Member Forum Leader

    Any indication of low pressure or have you hooked up a gauge to check refrigerant pressures?
  6. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    wire kicked, board issue? Capacitor?
    Compressor would start, even with low or no refrigerant.
    Last edited: Dec 7, 2018
  7. DaveO

    DaveO New Member

    Thanks for the responses, I'm having the refrigerant checked tomorrow a.m., also ordered a new capacitor even though my analog multi says its ok , check this pick out of the board, looks like a few hot spots?
  8. arkie6

    arkie6 Member Forum Leader

    I see this all the time at work. It is not uncommon to see a circuit board turn brown from heat under a power resistor like that. Rarely does this cause any sort of malfunction. I would probably be more concerned with that "black box" (I can't really tell what it is, a relay?) directly above those resistors generating the heat that turned the board brown. If that is a relay, the heat from the resistors directly below it could cause it to fail. Do you have a board schematic? What is the on-board designation for that black box above R24 and to the left of R32?
  9. DaveO

    DaveO New Member

    Thanks arkie6, I'm not finding a schematic for the control board anywhere.
    Yesterday I did however bypass the control board and the compressor will start and run. I also bypassed the control board and the load side circulation pump starts and runs as well. My thinking is I have a problem somewhere on the control board, any thoughts? In addition I pressure tested the refrigerant and it is still charged as well.
  10. arkie6

    arkie6 Member Forum Leader

    Get the nameplate data off that "black box" I mentioned above and I will look up the datasheet to see if I can find anything, but honestly, unless you have the ability to remove and test individual components on the board, it sounds like you need to replace the entire control board.

    What is hiding behind that wire bundle in the lower left corner of the circuit board? Is there an AC input fuse there by chance? If so, check that and make sure it isn't blown.

    One thing you might try is unplugging and plugging back in all cables and devices that can be disconnected from the board to verify no faulty connections. Closely inspect pins on both the board and cable to verify in good condition. I would shut the power off before you did this.

    Also make sure the circuit board has a good ground connection. Without a schematic I'm not sure where it is getting its ground reference, but it may be through the board mounting screws, so make sure those screws are tight.

    With power on the board, I would also check with a meter to verify that you have power coming into the board. Unfortunately, without a schematic, I'm not sure where that point on the board is. That red device on the far left of the board is a Metal Oxide Varistor (MOV) and they are normally used to clamp voltage surges and are typically installed across the AC input to circuit boards. You could probe the legs of the MOV with a volt meter and see if 24 volts AC is present.
  11. DaveO

    DaveO New Member

    Thanks for the info arkie6! I am looking for a control board today but will try the things you mentioned above. Do you think I will be able to easily find a replacement control board for this older EW series Waterfurnace?
  12. arkie6

    arkie6 Member Forum Leader

    I have no idea regarding availability of that control board. If you can't find a new board, you might consider taking that one to a TV / electronics repair guy in your area and see if he can diagnose and fix any failed components.
  13. SolarPower

    SolarPower Member

    I would check the transistor right above R48. The board has been hot there. It is a easy check with your meter.

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