State GTS-710-PIEA - Manual (Page 21)

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PUMP CONTROL CONNECTIONS
The water heater can be used to control a recirculation pump. Proper pump control helps to
preserve the life of the system and saves energy as well.
The water heater pump control port is a “normally-open dry contact”, and therefore needs
additional components to properly control a recirculation pump. To control a recirculation pump,
connect the pump to the “Pump connector” in the water heater as shown in the diagram below.
(In a multi-unit system, connect the pump ONLY to the “PARENT” unit.) The pump is to be
connected using suitable relays shown in the diagram below.
Please make sure the relays are properly rated for the recirculation pump.
Using the water heater’s internal thermistors as a temperature control, the recirculation pump
will only turn on when recirculation is needed.
CAUTION: In a multi-unit system, the pump must be connected to the
“Pump” connector in the “PARENT” unit only. If the pump is connected to
any of the “CHILD” units, the pump will not work.
Power supply for relay
Power supply for pump
120 VAC
220 VAC etc
120 VAC
220 VAC etc
for relay
Thermal relay
Recirculation
pump
Connect to this “Pump connector”.
These components are NOT included with
water heater and are external to the unit.
They must be acquired separately.