V4+R VRF 50/60Hz 
201608    91 
Part 5 - Diagnosis and Troubleshooting 
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.  Refer  to  Figure 
5-4.15.) 
 
Step 7: Add compressor oil 
  Add 1.2L of oil to the new compressor through the discharge pipe, using a funnel. 
  Add 1.2L of oil to each of the compressors from which oil was drained in Step 3. 
  Only use FV68H 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 5L in 8-12HP units and 7L in 14-22HP 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 V5 X Engineering Data Book, Part 3. 
 
Figure 5-4.16: Inspecting compressor oil 
 
   
Figure 5-4.15: Compressor piping 
This oil is black 
- it has been 
yellow, but is clear 
and transparent and 
the condition is 
transparent but there 
are impurities which 
oil indicates 
abnormal 
system 
This oil contains