Carrier VECTOR 6500 Operation & Service Manual page 138

Alarm
Steps
NO.
12 HIGH COOLANT TEMPERATURE
•
TRIGGER–ON: When in Engine Operation: for ambient temperatures below 120°F (48.9°C) Engine
coolant temperature is above 230°F (110°C), or Ambient temperatures above 120°F (48.9°C),
engine coolant temp is over 241°F (116°C), or Engine coolant temperature is between 230 and
241°F (110 and 116°C) for more than 5 minutes.
•
UNIT CONTROL:
•
RESET CONDITION: Auto Reset after 15 minutes if the engine coolant temp falls below 212°F
(100°C), 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 Coolant Level
a. Check coolant level in overflow
bottle.
Do not remove the cap from a hot
radiator or bottle; if the cap must be
removed, do so very slowly in order
to release the pressure without
spray.
b. Inspect connecting tube between
overflow bottle and radiator.
2 Check For Bad Eng Coolant Sensor Alarm
Check for Alarm 129.
3 Check Freeze Point Of Coolant
Use Coolant Tester to check
concentration of anti-freeze
mixture.
4
Check Airflow Through Radiator & Condenser Coil
a. Inspect condenser & radiator.
b. Check condenser fan rotation /
operation.
5 Check Water Pump Belt
Check engine water pump belt.
6 Check Engine Coolant Temperature Sensor
a. Inspect sensor & connector pins &
terminals.
b. Check sensor resistance.
(See Note 3 page 7−2.)
Additional steps on the next page.
Alarm/Cause
Engine Operation: Engine and unit shutdown and alarm.
Standby Operation: Will not activate in standby.
WARNING
7−5
Corrective Action
Level must be in the normal range.
Connections must be airtight. No leakage or holes in
tube.
Alarm conditions must be corrected and the alarm
cleared to continue.
Must be between 40% to 60% Ethylene Glycol to
water mixture.
Ninety percent or more of the coil surface must be
undamaged. No "dead" air spaces. Condenser / Ra-
diator coil must be clean.
Fans should operate correctly. Air should be directed
in through the grill, and into the engine compartment.
No Glazing, no cracking, no slipping.
No damage to sensor.
No damage, moisture, or corrosion in connector.
10,000 Ohms @ 77°F (25°C.) Refer to Table 8−5 for
complete table of temperatures and resistance val-
ues.
62-11389