Hi all - there are similar threads out there, but none that seem exactly right. I want to use my Z4 to control switching between heat pump and natural gas heater (in the way it would switch between solar and natural gas).
I have an inground pool and spa with VSP and Natural Gas Heater controlled by a Z4 Aqualink. This was the set up that came all done when we bought the house.
I want to buy a heat pump and add it inline with (ahead of) the Gas Heater. We're trying to get the temps up for longer around the year, and off fossil fuels as much as possible, but I don't want to get rid of the gas heater as it helps to get the hot tub up to good temps. This is reasonably straight forward - most heat pumps I'm looking at turn on when the pool pump starts pushing water through them... so just by turning on the VSP via Z4 scheduling, the pool will begin to heat up to the temperature set on the heat pump (no control from the z4 required).
However, there will be times when we want the extra burst of heat from the gas heater... but due to where I have to place the heat pump, I don't want to pump water through the lines to the heat pump and back and then into the gas heater.
What I want: when I turn the spa heat option on via the z4, what I want the z4 to do is to read the temperature of the "solar (though it's actually the heat pump return)", determine that it is not hot enough for the spa, then close a JVA bypass to the heat pump to then make the loop a lot smaller/more efficient (as it would with solar). Mechanically, this all seems possible through various settings on Z4 (prioritize solar etc)... but I've not done it practically yet.
My questions: Are there issues I'm not thinking about? Might the z4 close the (solar) JVA on start up because the water from the heat pump is not warm enough yet?
Any thoughts/experiences welcome. Thanks in advance
I have an inground pool and spa with VSP and Natural Gas Heater controlled by a Z4 Aqualink. This was the set up that came all done when we bought the house.
I want to buy a heat pump and add it inline with (ahead of) the Gas Heater. We're trying to get the temps up for longer around the year, and off fossil fuels as much as possible, but I don't want to get rid of the gas heater as it helps to get the hot tub up to good temps. This is reasonably straight forward - most heat pumps I'm looking at turn on when the pool pump starts pushing water through them... so just by turning on the VSP via Z4 scheduling, the pool will begin to heat up to the temperature set on the heat pump (no control from the z4 required).
However, there will be times when we want the extra burst of heat from the gas heater... but due to where I have to place the heat pump, I don't want to pump water through the lines to the heat pump and back and then into the gas heater.
What I want: when I turn the spa heat option on via the z4, what I want the z4 to do is to read the temperature of the "solar (though it's actually the heat pump return)", determine that it is not hot enough for the spa, then close a JVA bypass to the heat pump to then make the loop a lot smaller/more efficient (as it would with solar). Mechanically, this all seems possible through various settings on Z4 (prioritize solar etc)... but I've not done it practically yet.
My questions: Are there issues I'm not thinking about? Might the z4 close the (solar) JVA on start up because the water from the heat pump is not warm enough yet?
Any thoughts/experiences welcome. Thanks in advance
