Basis of Screw type vapour compression chillers Trips

[ArunavaSinha]

Fisrt of all, let me accept that i am novice in HVAC industry. For one of our project, vendor have supplied 225 TR Screw type vapour compression chillers with various chiller trip set points. I like to know the basis of following Chiller Trip set points. Like there is a chiller trip on Evaporator Pressure "LOW". I would like to know why this set point is given, i.e why chiller have to trip on low evaporator pressure.

Likewise I would like to know the basis of following Chiller Trips

(a) Evaporator Pressure "LOW"
(b) Chilled water temperature "LOW"
(c) Condenser pressure "HIGH"
(d) Oil Feed pressure "LOW"
(e) Compressor Motor winding temperature “HIGH”
(f) Compressor Suction Pressure “LOW”
(g) Compressor Discharge Pressure “HIGH”

Thanks in advance

 

[willard3]

You should contact the manufacturer for this information

 

[DrRTU]

Adding to Willard3, most mfgs have a diagnostic flow chart to help troubleshoot based upon trip(s). Finding the root cause of the trip is the key - not just the trip. Troubleshooting should be undertaken by a skilled technician. Low evap pressure can be caused by numerous items such as low flow, low charge or too much capacity. The trips are designed to protect the machine from damage.

 

[MintJulep]

(a) Evaporator Pressure "LOW" Because low evaporator pressure is an indicator of many problems.
(b) Chilled water temperature "LOW" Because maybe the flow is reduced because of a problem in the loop.
(c) Condenser pressure "HIGH" Because the heat can't get out.
(d) Oil Feed pressure "LOW" Because the bearings will fail.
(e) Compressor Motor winding temperature “HIGH” Because the motor will fail.
(f) Compressor Suction Pressure “LOW” Because low condenser pressure is an indicator of many problems.
(g) Compressor Discharge Pressure “HIGH” Because the heat can't get out.