Waterfurnace Synergy 3D Question

Discussion in 'Maintenance and Troubleshooting' started by ajmert, Mar 16, 2013.

  1. ajmert

    ajmert New Member

    I have a 6 ton Waterfunace Synergy 3D that is controlled by a Honeywell TH8320U thermostat. When the forced air runs is there some way to determine if it is running in stage 1 or stage 2? When I turn the heat way up I can hear the thermostat calling for stage 2 but I do not notice any difference in fan speed from the Synergy. The installer had Y1 and Y2 jumpered on the Synergy, I removed the jumper and connected Y2 on the Synergy to Y2 on the thermostat.

    Thanks in advance!

    FYI - this is a stand alone system - there is also a NG FA furnace controlled by a seperate thermostat for backup.
     
  2. ACES-Energy

    ACES-Energy Member Industry Professional Forum Leader

    A couple ways come to mind quickly, some easy and some technical...

    Can you stand near the unit and tell a different noise with the compressor?
    Are you handy enough to put an amp measuring device on the wires to tell if amp draw changes?

    I got a call a couple weeks about a system that has been in for 3 winters by another out of business contractor and they were calling saying unit was not keeping up at night. It was a 6-ton envision unit that the thermostat was calling for 2nd stage heat. I had the call at both the thermostat and fan board but was not engaging second stage of the unit. Upon further investigation the Y2 wire was loose between the control board and comfort alert system, got it working and customer has never been so happy, as they thought the unit was undersized, but upon running for a few weeks, the unit would now successfully cycle between stage 1 and 2 and keep them warm!
     
  3. ajmert

    ajmert New Member

    I have been right next to the unit with the cablnet door open, had the wife turn the stat way up, hear the stat click (assuming Y2 call) but hear no change in the fan or compressor.

    Where is the best place to test amp draw?

    Any idea why the installer would have jumpered Y1 and Y2 on the Synergy board?

    Thanks Again!
     
  4. ajmert

    ajmert New Member

    GOT IT! I double checked the Y2 wire per your instructions and discovered the Y2 terminal on the stat was bent causing a disconnect.... straightened the terminal - reinstalled the stat - 2nd stage is back in action.

    Still curious about the jumper in the Synergy between Y1 and Y2... It is an open loop system with a well pump - Is it more efficient to run the geo on stage 2 than it is to run the well pump for a longer period of time in stage 1??
     
  5. engineer

    engineer Well-Known Member Industry Professional Forum Leader

    My experience is that the difference in compressor noise between Y1 and Y2 is small and short-lived...one has to be right next to the compressor and listen to it shift.

    Amp meter suggestion is good, provided one has access to an amp meter and isn't put off by the prospect of working near potentially lethal voltages.
     
  6. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    When in doubt, watch the electric meter for faster movement.
     
  7. engineer

    engineer Well-Known Member Industry Professional Forum Leader

    Low tech but effective...

    To perceive the faster meter movement, spinning disk or higher frequency LCD flashes (approximately 200-300 Watts per ton) ensure that other heavy electric loads (resistance water heater, electric clothes dryer, electric range, aux heat strips, to name some) are off.
     
  8. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

    Since I bought an electric test meter I no longer time any utility meter, maybe a gas meter if I can not find my manometer.

    LOL

    My guess is the Y1 to Y2 jumper was a field repair while commissioning the system.

    Mark
     
  9. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    My guess is it was the only way installer could get Y2 to go on since the thermostat was screwed up. He must have forgotten to bring the replacement stat.;)
     
  10. ajmert

    ajmert New Member

    Looks like everything is running as it should - thanks for the help! Now I need to make adjustments to make it as efficient as it can be. Is a higher or lower water flow make it more efficient? Does a higher temp differential between EWT and LWT make it more efficient?
     
  11. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    Higher temp differential between EWT and LWT mean lesser flow. More flow is better but only to the point where it does not cost you more pumping power.
     
  12. ajmert

    ajmert New Member

    A lower Delta T is more efficient than a higher Delta T? I am just wondering which is more efficient. I have a variable speed pump, flow meter and temp sensors - just need to know where they should be to get the most out of the system with the least amount of power consumption.
     
  13. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

    I would apply the clamp on amp meter and tinker.

    Mark
     
  14. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    Technically yes, in a properly functioning geo heatpump, a lower delta T indicates more flow, which slightly improves the COP. There is very quickly a balance point, since the pressure drop associated with higher flow increases significantly faster, so the pumping power quickly exceeds the benefit from the higher COP associated with higher flow.
     

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