Hey RE members
I read many of the posts related to screw chillers.
I am maintaining a bitzer screw chiller and having issues with the calculation of its overall efficiency.
I want to compare it with my existing recip with the same operating conditions and capacity.
For part load i found recips serve better.
I want to change over to screw but am unable to calc reduction in power consumption for screw.
Capa: 175TOR
SST: 5 dC
SDT: 40dC
ref: NH3
Sys: vapor comp. PLC based auto sys with VFD on compressor motor for part load application & to maintain constant suction P.The slide valve mech is operated via the PLC provided.Energy mtr and flow mtr installed for capacity calc.

Also a second problem is of the oil carry forward which gets accumulated in the evap.This particularly happens at low load conditions.
Any suggestions for some revision in the system?Sys uses triple effect coalescer type seperator.