Panasonic Cs W50btp Cu W50bbp8 Cu V50bbp8 Repair Manual

							26.2. Freezing prevention control
 1. Operation
During cooling mode operation, after 9 minutes have passed since the compressor turned on, the outdoor unit will stop its
operation when the temperature detected by the indoor unit pipe temperature sensor is 2°C or lower.
The indoor unit continues operating at the fan speed set by the remote control. (The remote controldisplay does not change.)
 2. Cancelling
This control is cancelled when the temperature detected by the indoor unit pipe temperature sensor is 15°C or higher, however
3 minutes waiting of prevention control is necessary.
(The 9 minutes countdown is cleared while the compressor is stopped.)
(The above illustration only shows the operation stops due to freezing prevention control of the indoor pipe temperature sensor.)
26.3. Heating mode operation time chart (Heat pump type)
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							(*2)
Outdoor unit fan control during heating mode operation
When the compressor is on during heating mode operation (except during defrosting and when the liquid bypass valve is on), the
outdoor unit fan is controlled by means of input (CN2) indicating whether the contact of the heating pressure switch on the outdoor
unit circuit board is open or closed.
(At the start of heating mode operation, the fan operates at HI speed.)
26.4. Hot starting
 1. Whenheating mode operation starts
 a. Start
Hot start control commences when heating mode operation starts.
 b. Operation
“PREHEAT” appears on the remote controldisplay . (Other display s remain unchanged.)
The indoor unit fan stops. In additio n, during hot starting, the louvre stays at the horizon tal position (angle 0°).
 c. Cancelling
Hot starting will be cancelled when the compressor is turned on or the indoor unit pipe temperature sensor is 18°C or higher
or after 1 minute of operation.
After cancellation, the “PREHEAT” display on theremote control disapp ears and the louvre operation returns to the previous
setting.
(However, for 2 minutes after cancellation, the indoor unit fan operates at LOW speed, and then returns to the previous
setting.)

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 2. Whendefrosting is completed
 a. Start
Hot start control commences when defrosting is completed.
 b. Operation
“PREHEAT” appears on the remote controldisplay . (Other display s remain unchanged)
The indoor unit fan stops. In additio n, during hot starting, the louvre stays at the horizon tal position (angle 0°C).
 c. Cancelling
Hot starting will be cancelled when the temperature detected by the indoor unit pipe temperature sensor is 18°C or higher,
or after a maximum 1 minute has passed since defrosting was completed.
After cancellation, the “PREHEAT” display on theremote control disapp ears and the louvre operation returns to the previous
setting.
(However, the indoor unit fan operates at LOW speed for 2 minutes after cancellation, and then returns to the previous
setting.)

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26.5. Indoor unit fan control when thermostat is off during heating mode
operation
When the thermostat of the indoor unit turns off during heating mode operation, the indoor unit fan operates for 2 minutes at LOW
and then stops. In additio n, 5 minutes after the thermostat of the indoor unit turns off, the indoor unit fan operates at LOW for 10
seconds, and at 3 minutes interval after that, it switches back to LOW operation for another 10 seconds.
26.6. Excess heat dissipation for indoor unit
The indoor unit fan continue its operation for 30 seconds after heating mode operation turns off in order to dissipa te excess heat.
 1. Whenheating mode operation has stopped
(LOWspeed for 30 seconds)
 2. Whenoperation is set to a mode other than heating by means of the OPERATION button
 3. If operation starts again during the 30 seconds mentioned at (1)
(The fan operates at LOW speed for the remainder of the 30 seconds and then hot start commences.)
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							26.7. Defrost mode operation time chart
 1. Start and completion of defrosting
 a. Start
During heating mode operation (including automatic heating), after the 45 minutes of defrostingcycle time has passed,
defrosting starts if the temperature detected by the outdoor unit heat exchan ger outlet sensor is 2°C or lower continuously
for 5 minutes.
However, if the outdoor unit fan is stopped, the start of defrosting will be delaye d by 5 minutes.
Then, the defrosting cycle will be 50 minutesfrom the start of heating mode operation.
 b. Completion
Defrosting mode operation will stop if the outdoo r unit heat exchan ger outlet sensor is 25°C or higher or after 12 minutes
of operation.
 c. Forced defrosting
If P8 on the outdoor unit circuit board is shorted while the compressor is on during heating mode operation and the
temperature detected by the outdoor unit heat exchan ger outlet sensor is 25°C or lower, defrosting is carried out regardless
of the current starting conditions.
 2. Operation
 a. During defrosting, the outdoor unit turns on the compressor and turns off the outdoor unit fan and the reversing valve.
 b. The indoor unit fan operates at LOW speed for 30 seconds upon defrosting starts, After this, the indoor unit fan turns off until
defrosting is completed.
(During defrosting, the louvre of the indoor unit stays at horizon tal position).
26.8. Indoor thermostat characteristics
 1. Thermostat characteristics during cooling and heating modes.
Operation modeSetting temperature (To)Room temperature (°C)
OperationDifferential
2.0K4.0K
Cooling16ON18.0____
OFF16.0____
31ON33.0____
OFF31.0____
Heating *116ON18.020.0
OFF20.022.0
29~31ON31.031.0
*1 (27~31)OFF33.033.0
1*If jumper wire J3 on the indoor unit circuit board is disconnected, the thermostat characteristics
during heating become 2K or higher.
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							NOTE:If the remote control display setting temperature (To) is 29°C or higher, the heating thermostat turns
on when the room temperature is 31°C.
 2. Thermostat characteristics during dry mode.
During dry mode operation, cooling mode operation is carried out in accordance with the indoor temperature as shown in the
table below.
*When modes (2) and (3) are active, dry mode operation starts when the cooling thermostat turns on.
When modes (2) and (3) have been stopped, the 10 min./5 min. times have no relevance. However, if the indoor temperature
is less than or equal to the remote control unit setting temperature, mode (4) is forcibly activated.
 3. Thermostat characteristics during automatic changeover operation
 a. Settings at the start of automatic changeover operation
Whenoperation changes from other modes to automatic changeover mode, operation starts at the temperature
characteristics given in the table below.
 b. Thermostat characteristic when switching between cooling and heating mode operation
Switching between cooling mode and heating mode operation is carried out as shown in the table below.
However, during automatic changeover operation, the operation will not change within 10 minutes after the thermostat has
switched off, either cooling mode or heating mode.
(The 10 minutes timer will be cancelled when operation is changed to other modes (manually) or when operation stops and
the thermostat turns on.)
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							 c. Thermostat characteristics during cooling mode and heating operation
The thermostat on/off characteristics in both operation modes are given in the table below.
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							26.9. Indoor unit fan control
 1. Fixing at LO, MED or HI
When LO, MED or HI isset, the relay switches and operation is carried out at that setting.
 2. Automatic fan speed
When set toAUTO, the indoor unit fan operation changes as shown in the table below.
(Indoor temperature) - (Setting temperature) (Units: K)
Mode / Fan SpeedHIMEDLO
Cooling+3 or higher+1.5 ~ 3Less than +1.5
Heating-3 or lower-1.6 ~ - 3More than -1.5
FanMED irrespective of temperature
26.10. Forced operation during restart
The compressor will not stop operating for 3 minutes after cooling mode operation starts, even if the indoor unit thermostat turns
off.
(However, the compressor will stop operating during this time if the indoor unit air intake temperature drops to 16°C and below
during cooling mode operation.)
26.11. Louvre control (modelswithlouvre)
 1. When mainpower is turned on
When thepower is turned on, indoor unit louvre position detection is carried out twice and then the indoor unit louvre stops.
 2. During initial operation
When the OFF/ON button is pressed to start the operation, the louvre moves through one full cycle, and then swings
automatically (if AUTO has been set using the remote control) or moves to the setting angle (ifMANUAL has been set using
the remote control).
 3. Whenoperation stops
When the OFF/ON button is pressed to stop the operation, the louvre moves through one full cycle, and then stops in the down
position, regardless of the remote control setting.
 4. When thermostat is off
Whenoperation is stopped by the indoor thermostat, the louvre moves through one full cycle, and then stops in the horizon tal
position, regardless of the remote control setting.
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							26.12. Outdoor unit fan excess heat dissipation control
 1. When theoperation is stopped while the compressor is in operation, the outdoo r fan will run at SUPER HI fan speed for
approximately 60 seconds and then stops.
26.13. Discharge temperature control
 1. Operation
When thedischarge temperature sensor detects a temperature of 100°C or higher during cooling mode operation, the liquid
bypass valve will be turned on.
 2. Cancelling
When thedischarge temperature sensor detects a temperature of 70°C or lower, the liquid bypass valve will be turned off.
26.14. Emergency operation
When the emergency operation switch(DSW1) on the outdoor unit printed circuit board is set to emergency, the emergency
operation is enable d. This allows normal operation to continue, with all abnormalities other than a discharge temperature
abnormality, high pressure abnormality or overcurrent abnormality being ignored.
26.15. DIP switch settings
 
    • 
• •  • 
Indoor unit printed circuit board (DSW1)
No.Setting typeFactory shipmentRemarks
1Group address setting
(twin/triple address setting)OFFWhengroup operation is being carried out using the remote control, this address is set
in order to control the order of starting for the indoor units. (If No. 8 is ON, twin/triple
address setting is carried out.)
2OFF
3OFF
4OFF
5Automatic restartONWhen set to ON,operation after a power outage resumes at the settings which were
in effect before the outage. (The backup time is semipermanent.)
6Filter sign timeOFFWhen set to ON, thefilter sign times can be set to 2,500 times.
7Louvre controlONWhen set toOFF, louvre control is disabled.
8Twin/triple slave unit settingOFFWhen set to ON, theunit is designated as a slave unit.
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							27 WIRED REMOTE CONTROL INSTALLATION MANUAL
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