Johnson Controls DHW18CMB21S, Руководство по обслуживанию

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14
Technical Information
Service Manual
2.4 Communication malfunction
Detection of the quantity of installed indoor units:
After 3min of energizing, if the outdoor unit does not receive the communication data of
a particular
indoor unit, the outdoor
unit will judge that
the
indoor unit is not installed
and the out door unit will give an error code
. If the outdoor unit receives the
communication data of that indoor unit later, the outdoor unit will treat that unit as
if
it is 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 high-pressure protection
2.6.1 When the high-pressure switch is detected cut off for 3s continuously, the compressor will enter high-pressure protection
as it stops when reaching set temperature. Meanwhile, the outdoor unit will send
a
signal of “high-pressure protection” to the
indoor units
(error code) .
2.6.2 After the appearance of high-pressure protection, when the high-pressure switch is detected closed for 6s
continuously, the compressor can resume running only after
the main power has been reset
.
2.7 Compressor overload protection
If the compressor overload switch
is detected
, the indoor unit will display the corresponding
error code
as it stops. When the
compressor stops for more than 3min 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 30min, the
protection times record will be cleared)
. T
he unit can not resume operation status automatically, but can resume running only
after
resetting of the main
power.
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. The
error code
will be cleared after 1min, the unit will restart and then detect if there is still phase
lock-out
protection. If the phase-lacking protection is detected for 6 times continuously, the compressor will not restart but can resume
running only after
resetting of the main
power. If the running time of the compressor is longer than 7min, the protection
times record will be cleared.
2.9 IPM Protection
2.9.1 When the I
PM
module protection is detected, the unit will stop, PFC is closed, display
ing IPM
protection malfunction.
After the compressor stops for 3min, the unit will resume operation status automatically
. If
the
IPM
protection is
detected for more than 6 times continuously (
i
f the running time of the compressor is longer than 7min, the protection times
record will be cleared), the system will stop and send the signal of module protection to
the
indoor unit. The unit can not
resume operation status automatically
until the main power is reset.
2.9.2
IPM
module overheating protection
2.9.2.1 When T
I
PM
η 8 5 ć , prohibit to raise frequency
.
2.9.2.2 When T
I
PM
≥ 9 0
ć
, the operation frequency of compressor
decreases
by 15% every 90s according to the present
capacity requirement of the complete unit. It will keep 90s after
decreasing
the frequency. After
decreasing
the frequency, if
T
IPM
≥ 9 0 ć , the unit will circulate the above movement until reaching the minimum frequency; if 85 ćζ T
IPM
ζ 9 0 ć , the
unit will run at this frequency
. W
hen T
I
PM
≤ 8 5
ć
, the unit will run at the frequency according to the capacity requirement
.
2.9.2.3 When T
I
PM
≥ 9 5 ć , the compressor stops. After the compressor stops for 3min, if T
IPM
ζ 8 5 ć , the compressor and
the outdoor fan will resume operation.