62-11389
7
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61
Alarm
NO.
Steps
Alarm/Cause
Corrective Action
98
CHECK HIGH TEMP THERMOSTAT
•
TRIGGER–ON: With the Main Power switch toggled out of the OFF position, the 1EVHTS circuit is
open.
•
UNIT CONTROL: Alarm AND no heat allowed.
•
RESET CONDITION: Auto Reset when the 1EVHTS circuit is okay for 15 minutes, or alarm may be
manually reset via keypad or by turning the unit off, then back on again.
NOTE: Follow the steps below until a problem is found. Once a repair or correction has been made, the active
alarm should clear itself (see reset condition above). Operate the unit through the appropriate modes to see if
any active alarm occurs. Continue with the steps below as necessary.
1
Check Evaporator Area For High Temperature
Check Evaporator temperature using
a test thermometer.
EVHTS opens when the temperature of the
evaporator becomes very high (Refer to Section
2.10). (For example, if the heaters are on when the
fan is not running.) If the temperature of the
evaporator section is very warm (hot), it will have to
cool down before the EVHTS closes.
2
Check High Temperature Thermostat (EVHTS)
Inspect thermostat and connector.
(See wiring schematic Section 10.)
No damage to thermostat.
No damage or corrosion in connector.
3
Check High Temperature Contacts
a. Contacts must be closed when
temperature is normal. Unplug
EVHTS and check for continuity.
Must be 0 (zero) Ohms. Cannot be opened (infinite
ohms) or shorted to ground.
b. Check for 12VDC on MPQC9.
12 VDC at MPQC9
Unplug EVHTS and check for 12 VDC at EVHTS pin
A harness connector.
Visually inspect and repair wiring as needed.
