– 66 –
NO.
Item
Specification outline
Remarks
9 High pressure
release
compressor
shutdown
control
This control function is aimed at automatically shutting down a compressor in an
outdoor unit depending on Pd pressure. It is individually performed by the header
unit and each follower unit.
1) Control details
• Compressors are shut down when Pd pressure reaches or exceeds P0.
• The compressor restart prevention timer (2 minutes 30 seconds) is set, and
the control terminated.
• When Pd
≥
P0 =
500 psi (3.45 MPa),
compressor No. 2 or
No. 3 (the last one of
three compressors in
terms of startup
order in a three
compressor
configuration) is shut
down.
• When Pd
≥
P0 =
508 psi (3.5 MPa),
compressor No. 1
(the first compressor
in terms of startup
order) is shut down.
10 Case heater
control
There are two types of case heaters: a compressor case heater and an
accumulator case heater. This control function is aimed at preventing the
accumulation of refrigerant in those cases, and is performed by all outdoor units.
If the power supply has not been turned on for a specified period before a
postinstallation test run, compressor failure may occur. Similarly, when starting
compressors after a long period of no power supply, it is recommended that the
power supply be turned on for a while before operation is resumed, just like a post-
installation test run.
This control function is sometimes used alongside an electrical charging of the
compressor motor windings. In this case, a charging sound may be heard, but this
is normal.
1) Control details
• The heaters are turned on while the compressors are turned off.
• The heaters are turned off when To sensor temperature becomes
≥
82.4°F
(28°C), and are turned back on when To sensor temperature becomes
≤
77°F (25°C).
• When the compressors are turned on, the heaters are kept on for 10
minutes.
Summary of Contents for MMY-MAP0724FT6UL
Page 35: ...35 3 5 Parts Layout in Outdoor Unit 072 type Model MMY MAP0724FT...
Page 36: ...36 096 120 type Model MMY MAP0964FT MAP1204FT...
Page 37: ...37 3 6 Parts Layout in Inverter Assembly 208 230V model MMY MAP0724FT9UL...
Page 38: ...38 208 230V model MMY MAP0964FT9UL MMY MAP1204FT9UL...
Page 39: ...39 460V model MMY MAP0724FT6UL...
Page 40: ...40 460V model MMY MAP0964FT6UL MMY MAP1204FT6UL...
Page 41: ...41 3 7 Outdoor Inverter print circuit board 3 7 1 Interface P C board MCC 1606...
Page 42: ...42 3 7 2 Inverter P C board for compressor MCC 1595 A3 IPDU For 208 230V model MMY MAP 4FT9UL...
Page 43: ...43 3 7 3 Inverter P C board for compressor MCC 1596 A3 IPDU For 460V model MMY MAP 4FT6UL...
Page 44: ...44 3 7 4 Inverter P C board for fan motor MCC 1610 FAN IPDU...
Page 45: ...45 3 7 5 Noise Filter P C board MCC 1608 A B For 208 230V model MMY MAP 4FT9UL...
Page 46: ...46 3 7 6 Noise Filter P C board MCC 1625 A B C For 460V model MMY MAP 4FT6UL...
Page 195: ...195...
Page 197: ...197...
Page 257: ...257 15 EXPLODED DIAGRAM PARTS LIST Outdoor unit 15 1 MMY MAP0724FT9UL...
Page 258: ...258 15 1 MMY MAP0724FT9UL...
Page 262: ...262 15 1 Inverter Assembly MMY MAP0724FT9UL...
Page 264: ...264 15 2 MMY MAP0964FT9UL MMY MAP1204FT9UL...
Page 265: ...265 15 2 MMY MAP0964FT9UL MMY MAP1204FT9UL...
Page 269: ...269 15 2 Inverter Assembly MMY MAP0964FT9UL MMY MAP1204FT9UL...
Page 271: ...271 15 3 MMY MAP0724FT6UL...
Page 272: ...272 15 3 MMY MAP0724FT6UL...
Page 276: ...276 15 3 Inverter Assembly MMY MAP0724FT6UL...
Page 278: ...278 15 4 MMY MAP0964FT6UL MMY MAP1204FT6UL...
Page 279: ...279 15 4 MMY MAP0964FT6UL MMY MAP1204FT6UL...
Page 283: ...283 15 4 Inverter Assembly MMY MAP0964FT6UL MMY MAP1204FT6UL...