Analysis of operating anomalies
Anomalies
Suction pressure
too low
Discharge pressure
too high
Oil level too low
Water flow fault
Motor winding fault
Fluid outlet temperature too high
Discharge temperature too low and close
to the condensing temperature
Probable causes
Presence of air in the chilled water circuit
Chilled water flow insufficient
Chilled water flow sufficient but chilled water temperature too
low
Lack of refrigerant fluid
Ventilation incorrect
Condenser clogged
Air too hot
Excessive refrigerant fluid load
Level not topped up after a maintenance operation
No water flow or flow less than the minimum value
Start-ups too close together, anti short-circuit cycle badly
adjusted
Magnetothermal switch badly adjusted or defective
Supply voltage too low
a) With an LP greater than normal
Incorrect adjustment of regulator setpoint
Thermal load greater than the capacity of the unit
Water flow too great
Electronic regulation defective
a) With an LP lower than normal
Lack of refrigerant fluid
Poor refrigerant fluid supply to the evaporator
The compressor's liquid intake is too great
Drain the chilled water circuit
- Check the opening of the valves in chilled water circuit
- Check the direction of rotation of the pump, make sure there
is no cavitation and that the pump capacity is sufficient
- Recalculate the thermal load and check that the unit is not
too powerful for the load in question
- Check the operation of the regulator
Search for the leak(s) and top up
Check the direction of rotation of the fans
Clean the coil in order to optimise its
operation
Switch to high speed.
Check that there is no recycling of air between
multiple adjacent units.
Check and adjust the load.
Top up the oil level
Check the opening of the water circuit valves and inspect the
pump(s)
Set the correct time between two start-ups
Adjust or replace the magnetothermal switch
Check the electrical installation and contact the energy
supplier if necessary
Correct the setpoint value
Two solutions:
Use the adjusting valve to adjust the water flow to the required
value
Bypass the evaporator in order to obtain a greater temperature
difference together with a smaller flow at the evaporator.
Check the operation of the temperature and capacity
regulators
Search for a leak and top up
Check the expansion valve
Make sure that the dryer filter is not clogged and that the
evaporator is not frozen
Check and adjust the refrigerant load
Check the expansion valve
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Instructions