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2.4 Communication
M
alfunction
Detection of the quantity of installed indoor units:
After 3
min
utes
of energizing,
if the outdoor unit doesn't receive communication signal / data, the outdoor unit will react as if
there is no indoor unit installed.
2.5 Overcurrent Protection
a. Overcurrent protection of complete unit
.
b.
P
hase wire current protection
.
c.
C
ompressor phase current protection
.
2.6 Compressor
H
igh-pressure
P
rotection
2.6.1 When the high-pressure switch
detects a
cut off
continuously
for 3
s
econds
, the compressor will enter high-pressure
protection as it stops when reaching
a
set temperature. Meanwhile, the outdoor unit will send the
error code
of “high-
pressure protection” to the indoor units
.
2.6.2 After the appearance of high-pressure protection, when the high-pressure switch is detected closed
continuously
for 6
s
econds
, the compressor can resume running only after cutting off the power and then putting through the power
again
.
2.7 Compressor
O
verload
P
rotection
If the compressor overload switch is detected
,
the indoor unit will display the corresponding malfunction
or error code
as it
stops when the indoor temperature
reaches a
set temperature. When the compressor stops for more than 3
min
utes
and the compressor overload switch is reset, the unit will resume operation status automatically. If the protection appears for
more than 6 times (if the running time of the compressor is longer than 30
min
utes
, the protection times record will be cleared),
the unit can not resume operation status automatically, but can resume running only after
resetting of the main power to the
outdoor unit.
2.8 Compressor Phase
Lock-out
Protection
When the compressor starts, if one of the three phases is detected open, the compressor will enter
phase lock-out
protection
/error code
. The
error code
will be cleared after 1
min
ute
, the unit will restart and then detect if there is still phase-
lock-out
protection. If the phase
lock-out
protection is detected
continuously
6 times, the compressor will not restart but can
resume running only after
resetting of the main power to the outdoor unit.
If the running time of the compressor is longer
than 7
min
utes
, the protection times record will be cleared.
2.9 IPM Protection
2.9.1 When the IPM module protection is detected, the unit will stop as the indoor temperature
reaches a
set temperature,
with
the
PFC closed,
and
display
s
IPM protection malfunction. After the compressor stops for 3
min
utes
, the unit will
resume operation status automatically
. I
f IPM protection is detected
continuously
for more than 6 times, the system will
stop and send the signal of module protection to
the
indoor unit.
If the running time of the compressor is longer than 7minutes,
the protection times record will be cleared.
The unit can not resume operation status automatically, but can resume running
only after cutting off the power and then putting through the power.
2.9.2 IPM module overheating protection
2.9.2.1 When T
IPM
η
1
85°F (85
ć
)
,
raising
frequency
is prohibited.
2.9.2.2 When T
IPM
≥
194°F (90°C),
the operation frequency of
the
compressor
decreases
by 15% every 90
s
econds
according
to the present capacity requirement of the complete unit.
The outdoor fan will run for 90 seconds at high spped
after
decreasing
the frequency. After
decreasing
the frequency, if T
IPM
≥
194°F (90°C)
the unit will circulate
the outdoor fan to
drop temperature below 85
°
C
until reaching the minimum frequency
.
I
f
185°F (85
ć
)
ζ
T
IPM
ζ
1
94°F (90
ć
)
, the unit will run
at this frequency
.
W
hen T
IPM
≤
1 8 5 ° F ( 8 5
ć
),
the unit will run at the frequency according to the capacity requirement
.
2.9.2.3 When T
IPM
≥
2 0 3 ° F (
9 5
ć
)
, the compressor stops. After the compressor stops for 3
min
utes
, if T
IPM
ζ
1
85°F
(
85
ć
)
, the compressor and the outdoor fan will resume operation.
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