Ontario Electrical Usage for Waterfurnace Premier Seems Way Too High

Discussion in 'Maintenance and Troubleshooting' started by Andrew Kulin, Mar 6, 2016.

  1. Andrew Kulin

    Andrew Kulin Member

    The wiring for my pumps is not set-up as shown on the wiring diagram found on page 14 of the manual. Two things stand out to me:
    1. the diagram indicates there should be wires connected to each of the L1-L2-L1 connectors, but on my system there are no wires connected to the left-most L1, but two connected to the rightmost L1.
    2. there is a single pair of black/white wires connected to the L1-L2 ports that lead to the pumps. Therefore I must conlclude that either both pumps are wired in series (both run when the system operates) or only a single pump is wired up. This would match up with my observed flows from a few weeks ago. I also listened yesterday ton the pumps with a cheap stethoscope and while both had sounds within, one was more noticeable (say 30% louder), which I could interpret as meaning the louder one was running, the less loud one then picking up sounds from the nearby running pump plus the sound of the flow through it, but not actually running.
    I have attached a photo of a sketch I made of the wiring in the furnace whilst looking inside the unit at an awkward angle. The wiring diagram specific to the pumps is also visible, look at the upper right for the pump wiring specified by waterfurnace.

    What are the implications of this non-standard wiring?

    Attached Files:

  2. mrrxtech

    mrrxtech Member

    It took a few minutes to arrive at the same conclusion, but as you say the pumps can't operate independently without using L1 Left.

    This means that if both pumps are powered with 220 vac and both are operating correctly, you should have more flow than you need in Stage 1 and Stage 2 would have its desired flow rate if the pumps were properly sized when installed. We know this isn't the case since your flows were low in both stages.

    You are using more power than you need to in Stage 1, assuming the two pumps are both running and were correctly sized.

    I would determine if both pumps are running. If not replace the bad pump with the same size pump, since they are in series on the volute/water side.

    On a Grundfos pump there is a cover that hides the electrical wire termination points. You can remove the cover to see the electrical termination points, which would be wise/safe to have the power off when opening the cover.

    With the power off you could pull one wire from the pump that was running quietly when checked by the stethoscope, then power back up and to see if the pump noise is from the other pump only.

    You could also do a voltage check on each pump to see if they both have 220 vac at the terminals when powered up.

    The chrome slotted cap on each Grundfos can be removed to check that the impellar turns freely when not running. The pumps sometimes freeze up and have to be freed up by manually turning the shaft inside the slotted cap. The cap can also be used to vent a new pump to make sure there is water lubricating the ceramic bearings.

    As I said a while back, fix the flow issue, then run the test again to check if there is another problem in your Unit.
  3. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    You are getting to it.

    Can you clarify, when you measured the compressor amps, did it included the pumps? I assume not the blower.

    To the dear Mrrxtech
    And as I said before, a flow around 12 gpm is not significantly impair the capacity of the unit, and is not significantly impair its efficiency. Check the performance tables in the spec sheet if you do not believe a word I say.
    Last edited: Dec 29, 2016
  4. Andrew Kulin

    Andrew Kulin Member


    The furnace compressor circuit includes the 2 pumps, and my amperage measurements were taken at the breker panel. Therefore the readings include compresssor and pumps.

    The blower is on the same circuit as the 3-bank elecrical heater.

    I have another problem now. I get a low pressure lockout and it appears neither pump is operating, i.e., no flow in the loop line. Confirmed by stethoscope - no sound of flow or pump running noises. I don't know if I buggered up the internal wiring this morning but I don't think so as I only looked at it mostly and took a couple of clamp readings without needing to force access to the wires, and I checked for any loose connections to the pump wires and found none. Unit would try a couple of times with geo, then trip the fault signal and run electrical heat. Ecobee though did not show this as Aux, but as Stage 1 or Stage 2

    Last night Ecobee indicated I ran into second stage a number of times which I thought odd as outside temps only between -4 to -8 (celsius). So wondering if pumps failed before I started poking around this morning. I will check my hourly usage for the 28th in the morning when it becomes available online to see if the power usage suggests aux heat was used last night.

    If it is the pumps, and I want to check if impellors are not jammed, is removing the silver cap on the pump do-able? If it is going to result in methanol spewing out onto the floor, loss of pressure and air in the lines then I am not going to do it.
  5. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    Make sure your coil is not frozen, and/or your low flow rate was secondly of an air locked loop circuit outside, significantly increasing the pressure drop.

    You could put your unit in A/C mode to see if the coil thaws, and you hear ice running through the pipes shortly after. Check the pressure drop first.

    Yes, if you have a pressurized system, it will spew out fluid if it is still pressurized.

    Why don't you check the fundamentals first: Do you have power going to the pumps, maybe your can power them directly from the breaker box. Maybe one, maybe two, that way you can find out.
  6. Andrew Kulin

    Andrew Kulin Member

    My hourly electric usage from yesterday confirms this lockout started overnight while we were sleeping as hourly use generally ranged between 7 -9 kW/hr. So nothing I did, just coincidental timing.

    I reset the furnace last night and this morning, the unit was showing lockout for low water flow (yesterday the lockout was low pressure).

    Regarding pressure drops, if pumps not working that canno be done, right? At rest pressure of the loop is measured at about 35 psi.

    I checked and the coils are not frozen. One thing I did note yesterday, the lower half of the accumulator tank was frosty if that means anything.

    As far as power to the pumps, no way to do so from the breaker panel as breaker powers compressor and pumps together. I can check the voltage at the L1-L2 connectors but that would be about it. From my look at the wiring yesterday, it appears the system was designed with both pumps running in Stage 1 and Stage 2 which seems really stupid to me and means I cannot check pumps individually.
    Last edited: Dec 29, 2016
  7. Andrew Kulin

    Andrew Kulin Member

    There is no power being directed to the pumps. Measured voltage at the L1-L2 connection and zero Volts.
  8. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

    If the compressor contractor was not closed there would be no voltage showing on your meter.
  9. Andrew Kulin

    Andrew Kulin Member


    I was measuring voltage starting before the unit started powering up, but kept measuringas it began cycling through its' start-up. According to the manual during Stage1 heating startup:
    1. the fan motor is started on low speed immediately (this happened)
    2. the 1st loop pump (in my case both because of the way it is wired) is energized 5 seconds after the Y1 signal is received and the compressor is energized on low speed 10 seconds after the Y1 input (yes)
    3. the blower fan is switched to medium speed 15 seconds after the Y1 input (yes)
    I was measuring teh voltage across the L1-L2 connector during all the above steps and zero voltage was measured.

    Am I messing up in my method of measuring the voltage and my interpretation of the zero voltage to the pumps based on the above?

  10. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

    Post a picture of the electrical makeup box showing L1 and L2 entering the machine from the electrical panel.

    I think I have this figured out. You said page 14 and I looked at them all. CSA code is different than here, and crossed supply wire can cause the no voltage issue.

    You might want retest the voltage from the pump block to ground.

    Do not electrocute yourself.

    Call me if need be.

  11. Andrew Kulin

    Andrew Kulin Member

    Mark, I have attached a number of photos:
    • breaker panel - the 60A circuit is for compressor and circ pumps, the 100A circuit is for the electric heat and blower- I don't see any cross connections per the CSA diagram
    • furnace - shows where the 60A power enters the unit - the BX cable is the power line to the circ pumps. the 100A circuit for electric heat come in to the unit above and to the right (out of picture)
    • circuit board - shows the board
    • circuit board and other electrical shows the top of the board and other connectors - you can see where the 60A feed is onnected to the unit (thick red/black lines roughly centre of shot)
    • L1 shows the L1 (right) wiring connections for the circ pumps
    • L2 shows the adjacent L2 wiring connections for the circ pumps
    Are these what you wanted to see?

    Attached Files:

  12. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

    I do not care about the pump conections until I see what is happening at the L1 and L2 area. Can you center and drop lower on a mix of your file 11 and 12? Back up some to include more wires. I can get close and use filters at this end.

  13. mrrxtech

    mrrxtech Member

    Check the Gray Wire Fuse L2. You more than likely blew the fuse since anything else would have given you an arc, and you would know when you messed up.

    A technician could check the fuse while powered by putting a Voltmeter across the fuse looking for 220vac.

    It might be wise to down power the Unit Compressor & Pumps, pull the fuse, and check it with and ohmeter, or take a look at the wire inside if it is a clear fuse.

    Find an equivalent fuse to replace it and get your Unit up and running.

    An incorrect Meter set up could have shorted out the fuse, such as being in the resistance mode while trying to measure voltage.

    Your wiring in the photos looks fine, it has to be the fuse.

    One more thing, if you have any devices that have a reset push button, check those if the fuse isn't bad.
    Last edited: Dec 29, 2016
  14. Andrew Kulin

    Andrew Kulin Member

    How are these?

    Attached Files:

  15. Andrew Kulin

    Andrew Kulin Member

    I presume the fuses are in these black cylinders? And it looks like they have to be opened with a flat head screwdriver? I'll look at this in the morning. the manual indicates the fuses are 240V/10A. I have googled these fuses and there seem to be a lot of choice in 250V but not so much in 240V, is that okay? And will these be available at local hardware stores or do I need to go to a specialty supplier? Haliburton, Ontario is a small town (maybe 3-4K people) so there's not going to be a lot of selection up here.

    Attached Files:

  16. mrrxtech

    mrrxtech Member

    250V should work since it's rated higher than the 240 V fuse.
    If you are using a Volt Ohm Amp Meter, you can use the Resistance settings to check that the fuse is open. If it's a short then it is working as intended.

    Assuming the fuse is bad, take it with you to make sure the replacement is the same physical size matches so it will work in the fuse holder. Use the markings on the fuse and do a search on line to see if there is one in your area. Your local heating & cooling company should carry the fuse since it's out of a "Furnace" as some people call a Geothermal Unit.

    Also call appliance shops if the Heating folks don't have the fuse. Old Time hardware stores seem to carry everything, so it wouldn't hurt to check with one as a last resort.

    The fuses are always the weak link when trouble shooting. If the wires and all the components on the circuit board look like yours do, the the problem is in the fuse. I did notice the White Wire on your Card at the thermostat hookup terminal appeared to be offset as if it was bent or no longer in the connector. You might take a look with a flashlight tomorrow.
  17. Andrew Kulin

    Andrew Kulin Member

    How does one actually get at this fuse? (black cylinder roughly center of attached photo)

    I tried gently turning with a flat head screwdriver but no movement. I don't want to force this and break anything and then need to replace the board

    Attached Files:

  18. mrrxtech

    mrrxtech Member

    I've never seen that type of fuse holder, but I do see the screw driver marks on it, so this problem has happened at some point in the past requiring the fuse to be inspected.

    As in all things (except plymouth lug nuts 1965 on the driver side which are left hand thead) the cap come off the same way you would remove the lid of a peanut butter jar if you were hungry, or Lefty Lucy, Righty Tighty from my military days.

    If it were my Unit I would ensure power was dead to the board after opening the supply breaker, then verifying with a voltmeter.
    Then use two fingers to hold the body of the fuse holder in place (preventing any torque from making its way down to the soldered joints of the fuse holder, while very lightly applying torque with a small large blade screwdriver, the size of the screwdriver slot in the top of the fuse holder.

    Lefty Lucy, then apply a little more torque until it turns. Feel for any torque twisting the fuse holder and counter it with your fingers.
  19. Andrew Kulin

    Andrew Kulin Member

    Evidence of screwdriver marks was from me this morning. I tried again by turning with a bit more effort and also by seeing if I could pull off the cover by inserting a small screwdriver in that slot that can be seen in the photo. No luck either way. Probably needs a special tool and so I have taken this as far as I can. Plus if the fuse is blown, then there would be a cause and putting in a new fuse would likely just blow again anyway. Going to have to make a service call.
  20. mrrxtech

    mrrxtech Member

    I saw the marks on the pictures last night. If you think you might have had your meter in the wrong setting at any time yesterday, you more than likely caused the problem.

    It's too much of a coincidence that you lost your pumps the first time you took readings on your Unit.

    I notice a small slot along the inside edge of the fuse holder, more than likely a place to put a screw driver to help remove the cap once it's unscrewed.

    How about it Mark or someone who has seen this type of fuse holder, how do you take that fuse cover off? Don't be shy Andrew needs some heat.

    Going off line to look for a similar fuse holder.
    Last edited: Dec 30, 2016

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