Trane TVR Pro CO Series Service Manual page 87

Compressor replacement procedure
Step 1: Remove faulty compressor and remove oil
 Remove the faulty compressor from the outdoor unit.
 Before removing the oil, shake the compressor so as to not allow impurities to remain settled at the bottom.
 Drain the oil out of the compressor and retain it for inspection. Normally the oil can be drained out from the
compressor discharge pipe.
Step 2: Inspect oil from faulty compressor
 The oil should be clear and transparent. Slightly yellow oil is not an indication of any problems. However, if the oil is
dark, black or contains impurities, the system has problems and the oil needs to be changed. If the compressor oil has
been spoiled, the compressor will not be being lubricated effectively. Abrasion will lead to a larger load and higher
current. More electric energy will get dissipated as heat and the temperature of the motor will become increasingly
high. Finally, compressor damage or burnout will result.
Step 3: Check oil in other compressors in the system
 If the oil drained from the faulty compressor is clean, go to Step 6.
 If the oil drained from the faulty compressor is only lightly spoiled, go to Step 4.
 If the oil drained from the faulty compressor is heavily spoiled, check the oil in the other compressors in the system.
Drain the oil from any compressors where the oil has been spoiled. Go to Step 4.
Step 4: Replace oil separator(s) and accumulator(s)
 If the oil from a compressor is spoiled (lightly or heavily), drain the oil from the oil separator and accumulator in that
unit and then replace them.
Step 5: Check filters(s)
 If the oil from a compressor is spoiled (lightly or heavily), check the filter between the gas stop valve and the 4-way
valve in that unit. If it is blocked, clean with nitrogen or replace.
Step 6: Replace the faulty compressor and re-fit the other compressors
 Replace the faulty compressor.
 If the oil had been spoiled and was drained from the non-faulty compressors in Step 3, use clean oil to clean them
before re-fitting them into the units. To clean, add oil into the compressor through the discharge pipe using a funnel,
shake the compressor, and then drain the oil. Repeat several times and then re-fit the compressors into the units.
(The discharge pipe is connected to the oil pool of the compressor by the inner oil balance pipe.)
Step 7: Add compressor oil
 Add 2.3L of oil to each of the compressors from which oil was drained in Step 3.
 Only use FV50S oil. Different compressors require different types of oil. Using the wrong type of oil leads to various
problems.
 Add additional oil to the accumulators such that the total amount of oil is 4L in 8-12HP units, 5L in 14-16HP units 6L in
18-22HP units and 9L in 24-30HP units.
Step 8: Vacuum drying and refrigerant charging
 Once all the compressors and other components have been fully connected, vacuum dry the system and recharge
refrigerant. Refer to the V6 Engineering Data Book, Part 3.
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