SpaShopper offers this Balboa dual sensor combination designed for standard 4-pin configurations in non-M7 systems. This assembly includes both temperature sensing and hi-limit protection sensors with Curley Finger style terminal ends on a 4-pin connector.

The temperature sensor features a 96" cable with 3/8" diameter probe, typically installed in a thermowell integrated into your spa shell. The hi-limit sensor provides a 31" cable with 1/4" diameter probe, commonly attached to the heater tube or heater body. While less common, some installations require both sensors on the heater assembly using either a thermowell or pinch plate mounting system (excluding M-7 configurations).

INSTALLATION NOTE: When servicing a temperature sensor installed in a shell-mounted thermowell, anticipate water discharge upon removal. Only qualified spa technicians should perform this replacement.

TROUBLESHOOTING GUIDANCE: These sensor assemblies rarely fail. An SN error code may indicate wire damage from animals or loose board connections rather than sensor failure. An OH error code could stem from a closed pressure switch, stuck relay, restricted heater flow, or other issues. Proper diagnosis is essential—SpaShopper cannot accept returns on used electrical components. Verify the problem before ordering replacement parts.