PROBLEM
Cooling fluid
temperature is high
Insufficient
coolant flow
Cooling coil is
partially frozen
No air flow
Safety devices
stops compressor
Safety devices
stops compressor
Faulty thermostatic gear
AIR WASHER
Low
humidifying
COOLING OIL
No cooling
No cooling
ELECTRONIC
STEAM
HUMIDIFIER
No
humidifying
ELECTRONİC
STEAM
HUMIDIFIER
Low
humidifying
ELECTRICAL
HEATER
Low heat
Low water flow
Low water level in water pan
Water distribution system is clogged
Strainer is clogged
High air flow
Refrigeration plant cycles on-off
Refrigeration plant capacity is insufficient.
Circulating pump or compressor fault.
Excessive heat gain in piping system.
Low load
Low suction temperature
Low air flow
Entering air temperature is too low
Thermostatic valve is closed
Power is not reaching elements or
control valve
Electronic power
failure
Heater elements
faulty
Faulty thermostat
gear
Steam supply rate
is low
Steam cylinder and
heating elements
are scaled
Safety cut-out tripped
Humidistat calibration is not correct
Steam-trap faulty
Electric power failure
Main contactor de-energized
Elements down to earth
Element failure
Elements disconnected / elements incorrectly
wired / wrong voltage
Controller cams faulty / wiring fault / equipment fault
Step controller is sticking
Thermostat set is too low
Thermostat set is too low
Power is not
available at
controller
Power available at
controller
Step controller faulty
Locate fault and restore power
Safety cut out tripped / poor duct design adjacent
to heater causes areas of uneven air velocity and
overheating of casing
Water treatment is insufficient
Heater elements
faulty
Humidistat setting
is not correct
Water is not
available in cylinder
Safety cut-out tripped
Control fault
Chilled water isolating
valves are closed
Cooling thermostat setting is high
High pressure cut-out disconnects
Solenoid valve closed. Low pressure
cut-out disconnects
Valves are partially closed or blockage
in the system
Refer to “no cooling, safety device stops
compressor” section
Refer to “ low air flow” section
Apply reheat or preheat
Unequal air velocity. Poor duct connections
Circulating pump or compressor fault
Blockage in system. Valves are closed. Leakage in piping
Float valve is off. Supply water is off.
Clean the system.
Clean the strainer
Refer to “high air flow” section
SYMPTOMS
POSSIBLE CAUSE
OTHER CAUSES OR ACTION
36
www.doguhvac.com
Air Handling Unit Installation, Operation And Maintenance Instructions
Water make-up failure or insufficient water level
in cylinder. Water treatment is required to avoid scaling.
Control valves are not opening fully. Manual
valves or partially closed
Manual valves or partially closed
Carry out maintenance or replacement
Thermostatic gear fault
Reset humidistat correctly
Check supply system
Water make-up failure or insufficient water level
in cylinder. Water treatment is required to avoid scaling.
Thermostatic failure. Circulating pump failure
Refer to “no air flow” section
Locate and correct fault
Fault in condenser. Fans or pumps stopped.
Condenser blocked. Heat rejection is not taking place.
Suction temperature is too low. Low airflow.
Entering air temperature is too low.
Oversized coil or compressor.
Содержание FourSeason KKS 062 - 046
Страница 12: ...10 www doguhvac com Air Handling Unit Installation Operation And Maintenance Instructions ...
Страница 17: ...Air Handling Unit Installation Operation And Maintenance Instructions www doguhvac com 15 ...
Страница 18: ...16 www doguhvac com Air Handling Unit Installation Operation And Maintenance Instructions ...
Страница 19: ...Air Handling Unit Installation Operation And Maintenance Instructions www doguhvac com 17 ...
Страница 51: ...Air Handling Unit Installation Operation And Maintenance Instructions www doguhvac com 49 NOTES ...
Страница 52: ......
Страница 53: ......