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– 64 –
NO.
Item
Specification outline
Remarks
7 Defrosting
control
(reverse
defrosting
method)
1. Defrosting commencement conditions
• During heating operation, the cumulative duration of operation in which TE1
sensor temperature falls below frost formation temperature is measured, and
when this reaches 55 minutes, defrosting control is introduced. (Just after
startup or upon changeover from cooling to heating, the target cumulative
duration is 25 minutes.)
* If the outdoor units are a combination of different models, all the units begin
engaging in defrosting control as soon as one of them satisfies defrosting
commencement conditions.
• Frost formation
temperature is
30°F (–1°C).
• If the outdoor
units are a
combination of
different models,
defrosting
operation, once
started, cannot
be manually
terminated for
about 2 minutes.
• To protect the
refrigerating cycle
circuit, the fan
mode may be
controlled during
defrosting.
• During defrosting
control,
compressors are
controlled so that
their speeds do
not exceed 70
rps.
• During standby
operation,
compressor
speed is in the
24-33.5 rps
range.
(It varies from
outdoor unit to
outdoor unit.)
2.
Details of defrosting control
1) All compressors currently in operation are operated at the minimum speed.
2) When a specified amount of time passes from the time the compressors reached
the minimum speed, the outdoor fans are turned off by closing the 4-way valves.
3) All compressors currently not in operation are turned on and operated at the
target rotational speed for defrosting control.
3. Defrosting termination conditions
• Defrosting termination conditions are met when the TE1 temperature sensor
measurement reaches a specified value (roughly 53.6°F (12°C)) a certain period
of time after the commencement of defrosting control. In that event, defrosting
termination control takes over.
* If the outdoor units are a combination of different models, defrosting
termination control commences when all the units satisfy the defrosting
termination conditions.
As long as one or more outdoor units are yet to satisfy the defrosting
termination conditions, those that have engage in standby operation.
4. Details of defrosting termination control
1) Compressors are operated at the standby operation speed.
2) When a specified amount of time passes, the 4-way valves are opened.
3) Indoor heating refrigerant recovery control is performed.
For control details, see “ 6. Refrigerant/oil recovery control”.
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...