Inverter models 30-I through 65-I and on/off models 40-O through 65-O. Two wires on terminals 5 and 6, a factory jumper to remove, and the heater's own setpoint pushed to maximum so the module owns the decision.
Automation control, two-wire heat only
1
Find the terminal strip
It is inside the heater's electrical compartment, on the side of the unit. The customer remote control switch connector is terminals 5 and 6.
2
Remove the factory jumper
A jumper wire links terminals 5 and 6 from the factory, which is what lets the unit run standalone. Take it out — your contact replaces it.
3
Land the heat call
Bring the two conductors from the module's dry contact to terminals 5 and 6, wired COM and N.O so the contact rests open.
4
Set the heater to 104 F
Raypak specifies setting the unit's temperature to 104 F (40 C). The module decides when heat is wanted, so the unit's own setpoint must not be the limit.
Things on the same terminal strip
Terminals
Purpose
5 and 6
Customer remote control switch — the heat call
L1 and L2
Incoming power, 208-230 V 60 Hz
P1 and P2
Pump control
Worth identifying before wiring so nothing lands on the wrong pair.
When it does not respond
Symptom
Where to look first
Heats regardless of the module
Factory jumper still across terminals 5 and 6.
Never heats
Contact wired to N.C instead of N.O, or landed on the wrong terminals.
Stops short of temperature
Unit setpoint left below 104 F.
Starts late every time
Compressor restart delay. Normal.
Pump behaves unexpectedly
P1/P2 pump control is active alongside the module's own scheduling.
iSmart Module relay driver board — KiCad schematic and BOM. H1/H2 and AUX1/AUX2 are optocoupled dry relay contacts; PORT A-D are an unbuffered RS-485 pass-through
