25TPB7: Installation Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
11
Troubleshooting
If  the  compressor  fails  to  operate  with  a  cooling  call,  the  table  below
(Resistance  table)  can  be  used  to  verify  if  there  is  any  damage to  the
compressor windings causing system malfunction. 
Major Components
2-Stage Compressor
The  2-stage  compressor  contains  motor  windings  that  provide  2-pole
(3500 RPM) operation. 
Compressor Internal Relief
The compressor is protected by an internal pressure relief (IPR) which
relieves discharge  gas into compressor shell when differential  between
suction  and  discharge  pressures  exceeds  and  550  -  625  psi.  The
compressor is  also protected by an internal  overload attached to motor
windings.
Compressor Control Contactor
The contactor has a 24 volt coil and is controlled by Y1 input from the
thermostat
Low Pressure Switch
Low  pressure  switch  is  provided  in  line  with  the  Y1  signal  to  the
contactor for protection. 
Care and Maintenance
For  continuing  high  performance  and  to  minimize  possible  equipment
failure, periodic maintenance must be performed on this equipment. 
Frequency of maintenance may vary depending upon geographic areas,
such as coastal applications. See Users Manual for information. 
Training
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questions.
Table 3 – Winding Resistance
Winding
Winding resistance at 70°F +/- 20°F
(21.11°C +/- 11.11°C)
Unit Size
024   036   048   060 
Start (S-C) 1.652 1.587 1.299 1.203
Run (R-C) 1.065 0.751 0.477 0.383