
4 MAINTENANCE AND REPAIR
4-13
4.8 Heat Trace Cable Thermostat (if applicable)
The thermostat (see Figure 4-6) opens or closes the circuit to energize or de-
energize the optional heat trace cable. When the internal water temperature falls
below 45°F (7.2°C), the thermostat closes the circuit to apply power to the heat trace
cable.
If you find the water output is not between the 55°F (12.7°C) and 65°F (18.3°C)
temperature range, the thermostat may need to be replaced. You need a continuity
tester for the following procedure.
You need a continuity tester and a cold and hot water supply for the following
quick test. If a warm or cold water supply is not available, remove and test the
thermostat in the subsequent procedure.
Figure 4-6. Thermostat Assembly
To perform a quick test on the thermostat:
1. Switch off the electrical power supply to the Therma-Flow
®
Plus.
2. Use a continuity tester at the thermostat connections in the junction box (see
Figure 2-4 Electrical Schematic on page 2-7).