Daikin WCT Series, Руководство по эксплуатации и техническому обслуживанию

Страница: 79 / 85

OMM WCT Centrifugal Chillers D-EOMWC01302-16EN - 79/84
EVAPORATOR :
CONDENSER
SYMPTOM RESULTS Possible Cause Remedy
Extreme Low
Suction Pressure
High Evaporator Approach Temperature with
High Discharge Temperature
Low Charge Check for leaks and add charge
EXV problem Remove obstruction
High Evaporator Approach Temperature with
Normal Discharge Temp
Dirty or restricted
evaporator tubes
Clean Evaporator Tubes and/or
Check water conditioning
Low Evaporator water leaving
Temperature with w/ Low Motor
Current
Insufficient Load for system
capacity
Check IGV motor operation and set point
of Evaporator water leaving temperature
cutout
Check Cutout setting and increase it if
necessary so Evaporator water leaving
temperature will not be so low and the unit will shut
down NOT causing low suction
pressure anymore
IGV might not be Full Open but not give enough load
due to linkage slippage etc.
High Evaporator
pressure
Low Evaporator water leaving
Temperature
IGV failed to open Check the IGV motor positioning circuit
System Overload Be sure the vanes are wide open without
overloading the motor until the load
decreases
Low discharge
superheat
Overall reduced performance due
to refrigerant accumulation in
Evaporator
Economizer float
valves are stuck
open
Adjust EXV until system stabilizes
SYMPTOM RESULTS Possible Cause Remedy
Extreme High
Discharge Pressure
Condenser Approach temperature is
higher than normal
Air in Condenser Take refrigerant charge out and put the unit
on a vacuum pump and then recharge
High Condenser water range with
normal Evaporator temperature
Insufficient
Condenser water
flow rate
Increase Condenser water flow rate
Overall performance loss Condenser Tubes
are dirty/scaled
Clean Condenser tubes and/or check water
conditioning
High Condenser
water entering
temperature
Reduce Condenser water entering
Temperature (check cooling tower and
water circulation)