Introduction; Scroll Compressor Components; Compressor Size; Performance - Danfoss VRJ Application Manuallines

Application Guidelines
Scroll compressor
components

Compressor size

Performance

4
AB141686422149en-US0401

Introduction

Danfoss VRJ for residential applications
developed by Danfoss is a complete package
consisting of a dedicated variable speed
compressor, variable speed drive, application
controller, electronic expansion valve (EEV), EEV
controller and sensors. Three nominal system
The motor stator is rigidly attached to the shell.
The rotor is shrink- t onto the eccentric shaft. The
shaft is supported by two bearings, one in the
crankcase and the second below the motor.
Variable speed technology o ers more exibility
in compressor selection than xed speed
compressors. Selection of the right variable
speed compressor size can be done by di erent
methods:
• Maximum cooling capacity: select a
compressor size that achieves the peak
load system cooling capacity demand at its
maximum speed.
• Nominal cooling capacity: select a
compressor size that achieves the nominal
system cooling capacity at a rotational
speed of 3000-4200 rpm (50-70Hz).
• Best Seasonal E ciency Ratio: select a
compressor size that achieves the minimum
The Danfoss VRJ compressors referenced in this
guide is a fully compliant scroll and actually
improves with run time in its early commissioning.
sizes are available (3, 4 and 5 TR), based on three
compressor models.
These Selection & Application Guidelines focus
on the variable speed scroll compressor.
system cooling demand at its minimum
speed. Ensure that the compressor is able to
cover the peak load system cooling capacity.
This selection makes the compressor to run
for a maximum of time at part load where
the system e ciency is highest.
Danfoss scroll compressors are manufactured
using the most advanced machining, assembly,
and process control techniques. In design of
both the compressor and the factory, very high
standards of reliability and process control
were rst priority. The result is a highly e cient
product with the highest reliability obtainable,
and a low sound level.
A seventy-two hour run-in is recommended to
meet performance expectations.