Refrigerant Volume Adjustment Mode Operation - Mitsubishi Electric PUHY-P200 Service Handbook

[5] Refrigerant Volume Adjustment Mode Operation

Since the refrigerant volume adjustment introduced in this chapter is just for emergency need, correct adjustment to
meet the rated refrigerant volume is difficult. Please judge for adequate volume by following the flow chart later under
normal operation mode.
1. Procedure
Depending on the operating conditions, it may be necessary either to charge with supplementary refrigerant, or to drain
out some, but if such a case arises, please follow the procedure given below
(1) Switching the function select switch (SW2-4), located on the outdoor unit's control board, ON starts
refrigerant volume adjustment mode operation and the following operation occurs
Operation The outdoor unit LEV1 diverges more than usual during cooling operation.
Notes: 1. Even if the refrigerant volume has reached a suitable level shortly after starting refrigerant volume adjustment
mode, if left for a sufficient length of time (once the refrigeration system has stabilized), there are times when
this level may become unsuitable.
1) The refrigerant volume is suitable;
When the refrigerant volume for TH5 - TH7 is more than 5K at the outdoor unit, and 5 to 15K for SH at the
indoor unit.
2) The current volume is suitable, however, may become unsuitable after a certain length of time;
When the refrigerant volume for TH5 - TH7 is less than 5K at the outdoor unit, or less than 5K for SH at the
indoor unit.
2. There are times when it becomes difficult to determine the volume when performing refrigerant adjustments if
the high pressure exceeds 2.0MPa.
3. Based on the following flowchart, use TH11, TH5, TH7 and Tc to adjust the refrigerant volume. Use the self-
diagnosis switch (SW1) on the outdoor unit main PCB to display TH11, TH5, TH7 and Tc.
4. Refrigerant adjustment mode operation will automatically stop in 90 minutes. By turning off and on SW 2-4,
the adjustment mode operation can be run again.
Self-diagnosis switch for TH11
1 2 3 4 5
ON
Self-diagnosis switch for TH7
1 2 3 4 5
ON
Using these, judge TH11, Tc - TH5 and Tc - TH7.
6 7 8 9 10
6 7 8 9 10
- 84 -
.
Self-diagnosis switch for TH5
1 2 3 4 5 6 7 8 9 10
ON
Self-diagnosis switch for Tc
1 2 3 4 5 6 7 8 9 10
ON