T-H2-DV/T-H2-OS Service Manual
Ver. 1.01
78
CONFIDENTIAL
12-14. Control for exhaust temperature (T-H2-DV only)
<Function and Purpose>
The exhaust gas temperature is controlled by the exhaust fan motor.
T-H2-DV is equipped with a thermistor and hi-limit switch for, detecting excess temperatures of the
exhaust gas within the flue and enabling the unit to safely stop operations if needed.
These
components are always monitoring exhaust gas conditions in order to prevent heat damage to PVC
(Plastic) venting. If the exhaust gas temperature exceeds 140°F, these components will enable the unit to
safely stop operations. (For the T-H2-OS model, these components are not available since there’s no
exhaust venting required.)
How the safety device works
There is a count that is used for checking the # of events of the exhaust temperature exceeding 140°F
detected by the exhaust thermistor or hi-limit switch for exhaust. If the count reaches 3, the “941”
error code will display and the operation is stopped safety.
