McQuay MWSC 010 Series Manual page 53

The LED indicator on the control panel:
FAN
AUTO HIGH MED
OFF ONLY ONE
ON ONLY ONE
OFF OFF OFF
OFF ONLY ONE
ON ONLY ONE
OFF ONLY ONE
ON ONLY ONE
OFF ONLY ONE
ON ONLY ONE
OFF ONLY ONE
ON ONLY ONE
OFF OFF OFF
OFF OFF OFF
OFF FLASH OFF
OFF OFF FLASH
OFF OFF OFF
- - -
By means of pressure readings:
PRESSURE
Data TOO
Circuit LOW
High pressure side
Low pressure side
High pressure side
Low pressure side
High pressure side
Low pressure side
The most common causes of air conditioner failure to "start" are:
1. Voltage fl uctuation not within ±10% of rated voltage.
2. Power supply interrupted.
3. Control settings improper.
4. Air conditioner is disconnected from main power source.
5. Fuse blown or circuit breaker off.
6. Improper temperature of water loop (water temperature below 13 °C or above 43 °C).
MODE
LOW COOL DRY
ON ON OFF
ON ON OFF
OFF OFF ON
ON OFF OFF
ON OFF OFF
ON OFF OFF
ON OFF OFF
ON ON OFF FLASH
ON ON OFF FLASH
ON FLASH OFF
ON FLASH OFF
OFF FLASH OFF
FLASH OFF OFF
OFF OFF OFF
OFF OFF OFF
OFF OFF OFF
- - -
TOO
HIGH
1. Overcharged with refrigerant;
2.Non-condensable gases in refrigerant circuit;
?
3. Too warm condenser water;
4. Insuffi cient water fl ow (cooling);
?
5. Outdoor coil dirty (cooling);
6. Air fi lter clogged/dirty (heating).
? 1.Poor compression/no compression (compressor defective);
? 2.Reversing valve leak (heating).
1. Undercharged with refrigerant;
2. Refrigerant leak;
?
3. Too low evaporator water;
4. Insuffi cient water fl ow (heating);
?
5. Outdoor coil dirty (heating);
6. Air fi lter clogged/dirty (cooling).
SLEEP
HEAT FAN
OFF OFF OFF
OFF OFF OFF
OFF OFF OFF
ON OFF OFF
ON OFF OFF
OFF ON OFF
OFF ON OFF
OFF OFF
OFF OFF
ON OFF OFF
ON OFF OFF
OFF OFF OFF
OFF OFF OFF
OFF OFF OFF
OFF OFF OFF
OFF OFF FLASH
- - - FLASH
PROBABLE CAUSE
Page 52
LED Status Analysis
- Cooling
- Auto fan cooling
- Dry mode
- Heating
- Auto fan heating
- Normal Fan
- Auto fan
- Auto cooling
- Auto fan and auto cooling
- Auto heating
- Auto fan and auto heating
- Compressor overload
- Room sensor missing
Outdoor water sensor
-
missing
Fault
- Indoor coil sensor missing
- Refrigerant leak
Water or compressor
problem