182
RT-SVX36G-EN
Maintenance
Electrical Phasing:
If it becomes necessary to replace a compressor, it is very important to review and follow the
Electrical Phasing procedure described in the startup procedure of the IOM.
If the compressors are allowed to run backward for even a very short period of time, internal
compressor damage may occur and compressor life may be reduced. If allowed to run backwards
for an extended period of time the motor windings can overheat and cause the motor winding
thermostats to open. This will cause a “compressor trip” diagnostic and stop the compressor
If a scroll compressor is rotating backwards, it will not pump and a loud rattling sound can be
observed. Check the electrical phasing at the compressor terminal box. If the phasing is correct,
before condemning the compressor, interchange any two leads to check the internal motor
phasing.
Precision Suction Restrictor:
Tandem manifold compressors that have unequal
capacity sizes utilize a precision suction restrictor to
balance the oil levels in the compressors. For tandem
manifold compressors in Intellipak units, this restrictor
is placed in the compressor indicated in
When replacing this compressor, it is imperative that
the proper restrictor is selected from those provided
with the replacement compressor.
When the compressors are restarted verify that correct
oil levels are obtained with both compressors
operating.
Figure 95. Precision suction restrictor
Table 68. Suction restrictor location (AC/EC)
25 Ton Standard Capacity
CSHD125
60 Ton Standard Capacity
CSHD142
25 & 29 Ton High Capacity
CSHD125
75 Ton Standard Capacity
CSHN176
30 & 36 Ton High Capacity
CSHD161
75 & 89 Ton High Capacity
CSHN184
40 Ton Standard Capacity
CSHD110
105 Ton High Capacity
CSHN250
50 Ton Standard Capacity
CSHD120
115 Ton High Capacity
CSHN250
