87
Page
240 (T-H3J), 340 (T-H3S) and 540 (T-H3) models Service Manial
Ver. 1.00
CONFIDENTIAL
Ceramic heating blocks
The two heating blocks focus on protecting the inlet and outlet piping inside the water heater, as well as
the front drum pipe.
The blocks will only activate based on what the freeze protection thermostat senses. The thermostat is
located on the intake port for Direct Vent Indoor models, close in vicinity to the inlet and outlet pipes for
Outdoor models. Electrical power is required for this feature to operate.
The heating blocks will activate if the thermostat senses a surrounding temperature
below 36.5 °F
.
Once they are on, the heating blocks will only deactivate if surrounding temperatures reach
above 46.4
°F
.