Mitsubishi Electric CITY MULTI PKFYI Series Operating manual

TECHNICAL & SERVICE MANUAL
Indoor unit
[Model Name] [Service Ref.]
INDOOR UNIT
R410A
Model name
indication PARTS CATALOG (OCB715)
No. OCH715
REVISED EDITION-A
June 2021
SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS
PKFY-P04NLMU-E PKFY-P04NLMU-E.TH
PKFY-P06NLMU-E PKFY-P06NLMU-E.TH
PKFY-P08NLMU-E PKFY-P08NLMU-E.TH
PKFY-P12NLMU-E PKFY-P12NLMU-E.TH
PKFY-P15NLMU-E PKFY-P15NLMU-E.TH
PKFY-P18NLMU-E PKFY-P18NLMU-E.TH
Note:
• This manual describes
service data of the indoor
units only.
OCH715 is void.
Revision:
•Outlines and dimensions
have been modified
in REVISED EDITION-A.
CONTENTS
1. SAFETY PRECAUTION ·······················2
2. PARTS NAMES AND FUNCTIONS ········4
3. SPECIFICATION ······························ 12
4. NOISE CRITERION CURVES ············· 15
5. OUTLINES AND DIMENSIONS ··········· 17
6. WIRING DIAGRAM ··························· 19
7. REFRIGERANT SYSTEM DIAGRAM ··· 20
8. MICROPROCESSOR CONTROL········· 20
9. TROUBLESHOOTING ······················· 27
10. DISASSEMBLY PROCEDURE ············ 35
MITSUBISHI
ELECTRIC
!Series PKFYI Wall Mounted ~~
CITY MULTI

32
OCH715A
1SAFETY PRECAUTION
Cautions for units utilizing refrigerant R410A
Charge refrigerant from liquid phase of gas
cylinder.
If the refrigerant is charged from gas phase, composition
change may occur in refrigerant and the efficiency will be
lowered.
Do not use refrigerant other than R410A.
If other refrigerant (R22, etc.) is used, chlorine in refrige-
rant can cause deterioration of refrigerant oil, etc.
Use a vacuum pump with a reverse flow check
valve.
Vacuum pump oil may flow back into refrigerant cycle and
that can cause deterioration of refrigerant oil, etc.
Use the following tools specifically designed for
use with R410A refrigerant.
The following tools are necessary to use R410A refrigerant.
Handle tools with care.
If dirt, dust or moisture enters into refrigerant cycle, that can
cause deterioration of refrigerant oil or malfunction of com-
pressor.
Do not use a charging cylinder.
If a charging cylinder is used, the composition of refrigera-
nt will change and the efficiency will be lowered.
Flare tool
Electronic refrigerant
charging scale
Vacuum pump adaptor
Size adjustment gauge
Gauge manifold
Torque wrench
Gas leak detector
Charge hose
Tools for R410A
If dirt, dust or moisture enters into refrigerant cycle, that can
cause deterioration of refrigerant oil or malfunction of com-
pressor.
If large amount of mineral oil enters, that can cause deterio-
ration of refrigerant oil etc.
Do not use the existing refrigerant piping.
The old refrigerant and lubricant in the existing piping
contains a large amount of chlorine which may cause the
lubricant deterioration of the new unit.
Use “low residual oil piping”
If there is a large amount of residual oil (hydraulic oil, etc.)
inside the piping and joints, deterioration of the lubricant
will result.
Store the piping indoors, and both ends of the
piping sealed until just before brazing.
(Leave elbow joints, etc. in their packaging.)
The refrigerant oil applied to flare and flange
connections must be ester oil, ether oil or
alkylbenzene oil in a small amount.
Ventilate the room if refrigerant leaks during
operation. If refrigerant comes into contact with
a flame, poisonous gases will be released.
Use the specified refrigerant only.
Never use any refrigerant other than that specified.
Doing so may cause a burst, an explosion, or fire when the
unit is being used, serviced, or disposed of.
Correct refrigerant is specified in the manuals and on the
spec labels provided with our products.
We will not be held responsible for mechanical failure,
system malfunction, unit breakdown or accidents caused
by failure to follow the instructions.
□~----

3
OCH715A
[1] Cautions for service
(1) Perform service after collecting the refrigerant left in the unit completely.
(2) Do not release refrigerant in the air.
(3) After completing service, charge the cycle with specified amount of refrigerant.
(4) When performing service, install a filter drier simultaneously.
Be sure to use a filter drier for new refrigerant.
[2] Additional refrigerant charge
When charging directly from cylinder
(1) Check that cylinder for R410A on the market is syphon type.
(2) Charging should be performed with the cylinder of syphon stood vertically. (Refrigerant is charged from liquid phase.)
Electronic weighing scale
Unit
[3] Service tools
Use the below service tools as exclusive tools for R410A refrigerant.
No. Tool name Specifications
1Gauge manifold · Only for R410A
· Use the existing fitting specifications. (UNF1/2)
· Use high-tension side pressure of 768.7 PSIG [5.3MPa.G] or over.
2Charge hose · Only for R410A
· Use pressure performance of 738.2 PSIG [5.09MPa.G] or over.
3Electronic weighing scale —
4Gas leak detector · Use the detector for R134a, R407C or R410A.
5Adaptor for reverse flow check · Attach on vacuum pump.
6Refrigerant charge base —
7Refrigerant cylinder · Only for R410A Top of cylinder (Pink)
Cylinder with syphon
8Refrigerant recovery equipment —
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5
OCH715A 4
2PARTS NAMES AND FUNCTIONS
2-1. Indoor unit
2-2. Wired Remote Controller <PAR-40MAA>
: Supported : Unsupported
Function PAR-40MAA
Slim CITY MULTI
Body Product size H × W × D (mm) 120 × 120 × 14.5
LCD Full Dot LCD
Backlight
Energy saving Energy saving operation schedule
Automatic return to the preset temperature
Restriction Setting the temperature range restriction
Function* Operation lock function
Weekly timer
ON/OFF timer
High Power
Manual vane angle
*Some functions may not be available depending on model types.
Wired remote controller function
The functions which can be used are restricted according to each model.
Filter
Air intake
Vane Air outlet
Louver
Front Panel
Remote control
receiving section
Operation
indicator lamp
Emergency operation
switch
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5
OCH715A
The functions of the function buttons change depending on the
screen.
Refer to the button function guide that appears at the bottom of
the LCD for the functions they serve on a given screen.
When the system is centrally controlled, the button function
guide that corresponds to the locked button will not appear.
▌1[ON/OFF] button
Press to turn ON/OFF the indoor unit.
▌2[SELECT/HOLD] button
Press to save the setting.
When the Main menu is displayed, pressing this button will
enable/disable the HOLD function.
▌3[RETURN] button
Press to return to the previous screen.
▌4[MENU] button
Press to bring up the Main menu.
▌5Backlit LCD
Operation settings will appear.
When the backlight is off, pressing any button turns the backlight
on and it will stay lit for a certain period of time depending on the
screen.
When the backlight is off, pressing any button turns the backlight
on and does not perform its function. (except for the [ON/OFF]
button)
▌6ON/OFF lamp
This lamp lights up in green while the unit is in operation. It blinks
while the remote controller is starting up or when there is an error.
▌7Function button [F1]
Main display: Press to change the operation mode.
Menu screen: The button function varies with the screen.
▌8Function button [F2]
Main display: Press to decrease temperature.
Main menu: Press to move the cursor left.
Menu screen: The button function varies with the screen.
▌9Function button [F3]
Main display: Press to increase temperature.
Main menu: Press to move the cursor right.
Menu screen: The button function varies with the screen.
▌0Function button [F4]
Main display: Press to change the fan speed.
Menu screen: The button function varies with the screen.
Controller interface
Function buttons
MENU
ON
OFF
RETURN SELECT
HOLD
83
83
Fri
Room
Set temp.
Mode Temp. Fan
Cool Auto
Main Main menu
Energy saving
Main menu: RETURN
Cursor
Operation
Vane·Louver·Vent. (Lossnay)
High power
Comfort
Main menuMain display
Menu screen
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Function guide
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6 7
OCH715A
The main display can be displayed in two different modes: “Full” and “Basic”. The factory setting is “Full”. To switch to the “Basic” mode, change the
setting on the Main display setting. (Refer to operation manual included with remote controller.)
▌1Operation mode
▌2Preset temperature
▌3Clock
Current time appears here.
▌4Fan speed
▌5Button function guide
Functions of the corresponding buttons appear here.
▌6
Appears when the ON/OFF operation is centrally controlled.
▌7
Appears when the operation mode is centrally controlled.
▌8
Appears when the preset temperature is centrally controlled.
▌9
Appears when the filter reset function is centrally controlled.
▌0
Indicates when filter needs maintenance.
▌1Room temperature
Current room temperature appears here.
▌2
Appears when the buttons are locked.
▌3
Appears when the On/Off timer, Night setback, or Auto-off timer
function is enabled.
appears when the timer is disabled by the centralized control
system.
<Full mode>
* All icons are displayed for explanation.
<Basic mode>
▌4
Appears when the Weekly timer is enabled.
▌5
Appears while the units are operated in the energy-save mode. (Will
not appear on some models of indoor units)
▌6
Appears while the outdoor units are operated in the silent mode.
(This indication is not available for CITY MULTI models.)
▌7
Appears when the built-in thermistor on the remote controller is
activated to monitor the room temperature (1).
appears when the thermistor on the indoor unit is activated to
monitor the room temperature.
▌8
Indicates the vane setting.
▌9
Indicates the louver setting.
▌)
Indicates the ventilation setting.
▌!
Appears when the preset temperature range is restricted.
▌@
Appears when an energy-saving operation is performed using a “3D i-
See sensor” function. (not available)
▌#Centrally controlled
Appears for a certain period of time when a centrally-controlled item is
operated.
▌$Preliminary error display
An error code appears during the preliminary error.
Most settings (except ON/OFF, mode, fan speed, temperature) can be
made from the Main menu. (Refer to Page 10.)
Display
Fri
Mode Temp. Fan
Room
Cool Set temp. Auto
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3
4
5
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Cool
Mode Temp. Fan
Set temp. Auto
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7
OCH715A
Menu structure
Not all functions are available on all models of indoor units.
Energy saving
Main menu Press the MENU button.
Move the cursor to the desired item with the F1 and F2 buttons, and press the SELECT button.
Operation
Initial setting menu
Manual vane angle
ON/OFF timer
Auto return
Clock
Main/Sub
Temp. range
Auto-OFF timer
Schedule
Daylight saving time
Clock
Administrator password
Operation locked
3D i-See sensor
High power
Vane · Louver · Vent. (Lossnay)
Comfort
Timer
Energy saving
Basic setting
Display setting
Operation setting
Restriction
Weekly timer
OU silent mode
Timer menu
Main display
Display details
Contrast • Brightness
Language selection
Auto mode
Continue to the next page.
Setback mode
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8 9
OCH715A
Maintenance menu
Service menu
Drain pump test run
Serial No. input
Lossnay
Diagnosis
Initialize remote controller
Remote controller information
Initialize maintenance info.
Test run
Model name input
Function setting
Error history
Maintenance password
Dealer information input
Error information
Test run menu
Maintenance information
Filter information
Cleaning
Settings menu
Check menu
Other menu
Auto descending panel
Descending operation
Self check
Descending adjustment
Remote controller check
Continue from the previous page.
Not all functions are available on all models of indoor units.
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9
OCH715A
Main menu list
Main
menu Setting and display items Setting details
Operation Vane · Louver · Vent.
(Lossnay)
Use to set the vane angle.
• Select a desired vane setting from 5 di󰀨erent settings.
Use to turn ON/OFF the louver.
• Select a desired setting from "ON" and "OFF."
Use to set the amount of ventilation.
• Select a desired setting from "O󰀨," "Low," and "High."
High power Use to reach the comfortable room temperature quickly.
• Units can be operated in the High-power mode for up to 30 minutes.
Comfort Manual
vane angle
Use to x each vane angle.
3D i-See sensor Use to set the following functions for 3D i-See sensor.
• Air distribution • Energy saving option • Seasonal airow
Timer Timer ON/OFF timer *1Use to set the operation ON/OFF times.
• Time can be set in 5-minute increments.
Auto-O󰀨
timer
Use to set the Auto-O󰀨 time.
• Time can be set to a value from 30 to 240 in 10-minute increments.
Weekly timer *1, *2Use to set the weekly operation ON/OFF times.
• Up to 8 operation patterns can be set for each day.
(Not valid when the ON/OFF timer is enabled.)
OU silent mode *1Use to set the time periods in which priority is given to quiet operation of
outdoor units over temperature control. Set the Start/Stop times for each day
of the week.
•Select the desired silent level from "Normal," "Middle," and "Quiet."
Energy
saving
Restriction Temp. range *2Use to restrict the preset temperature range.
• Di󰀨erent temperature ranges can be set for di󰀨erent operation modes.
Operation lock Use to lock selected functions.
• The locked functions cannot be operated.
Energy
saving
Auto return *2Use to get the units to operate at the preset temperature after performing
energy saving operation for a specied time period.
• Time can be set to a value from 30 and 120 in 10-minute increments.
(This function will not be valid when the preset temperature ranges are restricted.)
Schedule *1Set the start/stop times to operate the units in the energy saving mode for
each day of the week, and set the energy saving rate.
• Up to 4 energy saving operation patterns can be set for each day.
• Time can be set in 5-minute increments.
• Energy saving rate can be set to a value from 0% or 50 to 90% in 10% increments.
*1Clock setting is required.
*233.8°F (1°C) increments.

10
OCH715A
Main
menu Setting and display items Setting details
Initial
setting
Basic
setting
Main/Sub When connecting 2 remote controllers, one of them needs to be designated
as a sub controller.
Clock Use to set the current time.
Daylight
saving time
Set the daylight saving time.
Administrator
password
The administrator password is required to make the settings for the following
items.
• Timer setting • Energy saving setting • Weekly timer setting
• Restriction setting • Outdoor unit silent mode setting • Night set back
Display
setting
Main display Use to switch between "Full" and "Basic" modes for the Main display, and
use to change the background colors of the display to black.
Display details Make the settings for the remote controller related items as necessary.
Clock: The initial settings are "Yes" and "24h" format.
Temperature: Set either Celsius (°C) or Fahrenheit (°F).
Room temp. : Set Show or Hide.
Auto mode: Set the Auto mode display or Only Auto display.
Contrast •
Brightness
Use to adjust screen contrast and brightness.
Language selection Use to select the desired language.
Operation
setting
Auto mode Whether or not to use the Auto mode can be selected by using the button.
This setting is valid only when indoor units with the Auto mode function are
connected.
Setback mode Whether or not to use the Setback mode can be selected by using the button.
This setting is valid only when indoor units with the Setback mode function
are connected.
Mainte-
nance
Error information Use to check error information when an error occurs.
• Check code, error source, refrigerant address, unit model, manufacturing number,
contact information (dealer's phone number) can be displayed.
(The unit model, manufacturing number, and contact information need to be
registered in advance to be displayed.)
Filter information Use to check the lter status.
• The lter sign can be reset.
Cleaning Auto descending
panel
Use to lift and lower the auto descending panel (Optional parts).
Service Test run Select "Test run" from the Service menu to bring up the Test run menu.
• Test run • Drain pump test run
Input maintenance Select "Input maintenance Info." from the Service menu to bring up the
Maintenance information screen.
The following settings can be made from the Maintenance Information screen.
• Model name input • Serial No. input • Dealer information input • Initialize
maintenance info.
Settings Function setting Make the settings for the indoor unit functions via the remote controller as
necessary.
LOSSNAY setting This setting is required only when the operation of CITY MULTI units is
interlocked with LOSSNAY units.
Check
Error history
Display the error history and execute "delete error history".
Diagnosis Self check: Error history of each unit can be checked via the remote controller.
Remote controller check: When the remote controller does not work properly, use
the remote controller checking function to troubleshoot the problem.
Other Maintenance pass-
word
Use to change the maintenance password.
Initialize remote
controller
Use to initialize the remote controller to the factory shipment status.
remote controller
information
Use to display the remote controller model name, software version, and serial
number.