Mitsubishi Electric CITY MULTI PQRY-P200YMF-B Service Handbook page 77

Note :
1. Be sure to operate all indoor units because refrigerant is accumulated in stopped unit. Change mode to test run
mode for preventing stabilized operations from being disturbed by turning thermostat.
2. • Judge operation status as "stable" when high pressure is stabilized.
• Judge "stable" or "unstable" 3 minutes after starting compressor.
3. When turning on SW1 to
When LED 1 lights up
When LED 2 lights up
When LED 3 lights up
4. In the case of AL=1, adjustment is not required in principle. However, if liquid level is on the lower side, adjustment
is required for fear of refrigerant shortage because refrigerant is accumulated in stopped unit at the time on one-
unit operations.
5. Calculate difference of required refrigerant amounts between cooling and heating operations.
1 In case refrigerant piping length is roughly known
Replenish refrigerant observing the table below.
The total. length is that converted to ø19.05 liquid pipe size.
(kg/cm
Piping length (m)
60m or less
60~90m
90m or more
Liquid pipe size ø12.7
Liquid pipe size ø9.52
Liquid pipe size ø6.35
2 In case refrigerant piping length is not known
Additionally charge 10kg refrigerant.
6. When turning on SW, LED shows liquid level displayed mode.
When LED 1 lights up
When LED 2 lights up
When LED 3 lights up
7. When 7~B adjustments has been done without fail, AL=2 is not indicated even though maximum amount of
refrigerant is charged at C. Therefore, when AL=2 is displayed, excessive replenishment at 7 and 9, or calcula-
tion mistaken in C are judged as the cause.
1 2 3 4 5 6 7 8 9 10
, LED displays liquid level as follows.
ON
→
AL=0
→
AL=1
→
AL=2
High pressure
2
G) (MPa)
15 or less
(1.47) (1.47~1.67)
10kg
11kg
12kg
→ Actual length × 0.75
→ Actual length × 0.375
→ Actual length × 0.15
→
AL=0
→
AL=1
→
AL=2
15~17 17 or more
(1.67)
5kg 2kg
6kg 3kg
7kg 4kg
1 2 3 4 5 6 7 8 9 10
ON
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