Chiller Controls / Sequence of Operation

[NickParker]

I have attached the PID & chiller control box terminal drawing. In the terminal drawing wiring sheet, I could see the Interlock for chilled water pump but as per the PID, but the primary chilled water pump is not available.

How the controls should be achieved in this case? How would be the sequence of operation in this case?

 

[itsmoked]

The system needs to know if it can export the chilled water it's making or you could have a freeze-up in the chiller barrel. You need a signal proving the flow. It can be a flow switch or an auxiliary contact on the chilled water pump contactor but you definitely need something to protect the chiller.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[lilliput1]

There should be a specification and a submission of written sequence of operation. Typical sequence is wen the thiller is indexed to start first the chilled water pump and the condenser water pump are started then after both flows are detected (by flowmeters or differential pressure transmitters) the chiller compressoris started. On shutdown, the chiller compressor is first turned off then the chilled wster pump and condenser water pump. Check your company master specification on sequence of operations.