Danfoss VZH Series Application Guidelines

Application guidelines
84 FRCC.PC.023.A7.22
Manifold compressors
Installation and service
Failure analysis
Oil equalisation connection
Refrigerant charge limit
When one compressor in a parallel system fails,
the chance of foreign particles entering other
compressors is greatly increased. Therefore a
failure analysis must be done quickly to insure
further proper running conditions for the overall
installation (i.e. : oil analysis).
Danfoss Commercial Compressors has developed
specially adapted oil equalisation
Systems (VZH+SH) which ensure proper oil
balancing between the compressors. Hence,
Danfoss hybrid manifolding compressors
are equipped with rotolock connections and
patented design organ pipes:
• SH090 to 184: 1” 3/4 rotolock connection
allowing use of 1”3/4 - 1”1/8 Organ pipe and
1-1/8” oil equalisation line
• SH180 to 380: 2”1/4 rotolock connection
allowing the use of 2”1/4 - 1”3/8 Organ pipe
and 1-3/8” oil equalisation line
• VZH088/117: 1” 3/4 rotolock connection
allowing use of 1”3/4 - 1”1/8 Organ pipe and
1-1/8” oil equalisation line
• VZH170: 2”1/4 rotolock connection allowing the
use of 2”1/4 - 1”3/8 Organ pipe and 1-3/8” oil
equalisation line
Tandem piping design
Wiring and rotation
direction
For each tandem conguration specic outline
drawings are available as indicated on the
following pages. These drawings must always be
respected.
No changes shall be made to the indicated
tubing diameter and tting types. The oil
equalisation line shall be made of copper tube
and assembled in such a way that it does not
extend above the connection height and must be
horizontal so as not to trap oil.
All compressors in a tandem and trio unit must
be electrically wired individually.
Compressors should run with the correct rotation
direction. This can be achieved by having the
correct phase sequence on each compressor
motor terminal (L1-T1, L2-T2, L3-T3).
Compressor models Refrigerant charge limit (lb)
VZH088 + SH090 17.64
VZH088 + SH120 18.74
VZH117 + SH140, VZH117 + SH161, VZH117 + SH184 23.15
VZH170 + SH180 , VZH170 + SH240, VZH170 + SH295 38.6

Danfoss VZH Series Specifications

General

Brand	Danfoss
Model	VZH Series
Category	Air Compressor
Language	English