Automating a Jandy LT Heater

[jragan]

Hello all,
Just had our pool company convert our manually-controlled pool over to a new Jandy iq904-ps automation system. The system is functional except for heater control. The heater is a newer (last 5 years) LT model. The problem is that turning the Pool Heat or Spa Heat on at the RS Panel doesn't actually activate the heater. With Pool Heat and Spa Heat off at the RS Panel, if we try controlling the heater manually (like we used to) from the heater's own controls, it will indicate a Flow Rate problem (even though the pump is running, the valves are aligned properly and water is flowing through the heater like it should). For grins, I tried activating the heat function from the RS panel while the heater was manually turned on and the Flow Rate problem indicator turned off and the heater actually started heating. So apparently heat has to be enabled on the heater and the RS panel for heat to actually heat.

Is this expected operation with this specific heater? I've read that LTs may not support "remote control" is this the problem? Is there a way around it?

Thanks!

 

[jragan]

So it appears as though the pool company's engineer wants to leave the pool heater "On" permanently with the "Flow Rate" indicator flashing. Not sure how they wired things up but somehow they're purposefully causing a fault in the Flow Rate sensor to keep the heater from heating when it's "on" and using the RS controller to un-fault and therefore allow the heater to heat. Is this a valid setup? Is it going to hurt the heater to control its functions in this manner? Will it properly cool itself down after heating if heat is "disabled" by causing a Flow Rate fault?

 

[JasonLion]

Apparently the wired the automation panel into the heaters flow sensor circuit, so that the automation panel simulates a flow problem when it wants the heater off. That is a workable, if somewhat strange, setup.

It is completely normal in this situation to leave the heater turned on and the thermostat on the heater set to some very high temperature. Then the automation systems remotely turns the heater on and off. However, that is normally done through a remote connection provided specifically for that purpose on the heater, so you would not get a flow rate error.

 

[jragan]

Apparently the wired the automation panel into the heaters flow sensor circuit, so that the automation panel simulates a flow problem when it wants the heater off. That is a workable, if somewhat strange, setup.

It is completely normal in this situation to leave the heater turned on and the thermostat on the heater set to some very high temperature. Then the automation systems remotely turns the heater on and off. However, that is normally done through a remote connection provided specifically for that purpose on the heater, so you would not get a flow rate error.

Thanks Jason! I'm guessing that since this LT doesn't support "Remote Operation" (in the manual it says the LX does but the LT does not) that this is the work-around they used. As long as I'm not ruining the heater by doing things this way, then I'm happy with the solution.