Sharp FU-28H-S User manual

1
FU-28H-S
S4616FU28HS//
AIR PURIFIER
In the interests of user-safety (Required by safety regulations
in some countries) the set should be restored to its original
condition and only parts identical to those specified should be
used.
SERVICE MANUAL
FU-28H-S
MODEL
SHARP CORPORATION
Page
SAFETY PRECAUTIONS ..................................................................................................................................2
HOW SHARP AIR PURIFIER WORKS .............................................................................................................4
SPECIFICATIONS FOR THIS PRODUCT ........................................................................................................5
NAMES OF PARTS .......................................................................................................................................... 7
INSTLLATION................................................................................................................................................... 8
ABOUT THE FUNCTION................................................................................................................................ 14
ELECTRIC CIRCUIT........................................................................................................................................15
TROUBLESHOOTING GUIDE ........................................................................................................................22
REPLACEMENT OF MAIN PARTS .................................................................................................................24
OPERATION....................................................................................................................................................29
MAINTENANCE...............................................................................................................................................30
CUMULATIVE TIME CHECK FUNCTION (MAINTENANCE MODE)............................................................. 32
USE RESIN TABLE .........................................................................................................................................33
REPLACEMENT PARTS LIST ........................................................................................................................34
TABLE OF CONTENTS

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FU-28H-S
SAFETY PRECAUTIONS
When using electrical appliances, basic safety precautions should be followed, including the
following:
WARNING - To reduce the risk of electrical shock, fire or injury to persons:
• Read all instructions before using the air purifier.
• Use only a 220-240 volt outlet .
• Do not use the air purifier if the power cord or plug is damaged or the connection to the wall
outlet is loose.
•Periodically remove dust from the power plug.
• Do not insert fingers or foreign objects into the intake or air outlet.
When removing the power plug, always hold the plug and never pull the cord.
Electrical shock and/or fire from short circuit may occur as result.
• Do not use this air purifier near gas appliances or fireplaces.
• Remove the power plug from the wall outlet before cleaning the unit and when not using the
unit.
Electrical shock from bad insulation and / or fire from short circuit may occur as a result.
• If the power cord is damaged, it must be replaced by the manufacturer, its service agent, Sharp
authorized service or similarly qualified person in order to avoid a hazard.
•Do not operate when using aerosol insecticides or in rooms where there is oily residue, incense,
sparks from lit cigarettes, chemical fumes in the air or a humidity condition.
•Use care when cleaning the air purifier. Strong corrosive cleansers may damage the exterior.
•Only Sharp Authorized Servicers should service this air purifier. Contact the nearest Servicer for any
problems, adjustments, or repairs.
•The batteries must be removed from the remote control before disposal, and the batteries must be
disposed of safely.
CAUTIONS CONCERNING OPERATION
• Do not block the intake and air outlet.
• Do not use the unit near or on hot objects, such as range or where it may come into contact with
steam.
• Always hold the main unit when moving it.
Holding the front panel when carrying may cause it to detach, thus dropping the unit and resulting in
bodily injury.
• Do not operate the unit without the filter.
• Do not wash the Active Carbon Filter and the HEPA Filter.
Not only it does not improve filter performance, it may cause electric shock or malfunction.
• Clean the exterior with a soft cloth only.
The unit surface may be damaged or cracked.
In addition, the sensor may malfunction as a result.

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FU-28H-S
REMOTE CONTROL LIMITATIONS
DO NOT USE THE REMOTE CONTROL IN THE FOLLOWING LOCATIONS:
•Any location where there is inverter lighting equipment or electronic spontaneous lighting
equipment
The remote control may become inoperative. In this case, move away from such lighting equipment or
change direction.
•Location exposed to direct sunlight or fluorescent.
The unit may not receive signals from the remote control.
CAUTIONS WHEN MOUNTING THIS PRODUCT ON A WALL
•Avoid a location where the sensor is exposed to direct wind.
The unit may not operate properly.
•Avoid a location where curtains, etc., come into contact with the intake or air outlet.
Curtains, etc., may become dirty or a malfunction may occur.
•Avoid locations where the unit is exposed to condensation, due to drastic temperature changes.
•Place on a stable surface with sufficient air circulation.
•Install the unit on a wall, wooden pillar, crosspiece, etc. that is flat and strong enough.
•Do not install the unit on a thin wall or on plasterboard. The unit may fall down if installed on an
insufficiently strong wall.
•To install the unit on a wooden wall that is less than 10 mm thick, consult your dealer and have
them confirm the strength of the wall before installation.
•Always hold the main unit when moving it.
Holding the front panel may cause it to become detached, thus dropping the unit and resulting in
bodily injury.
•Do not install when there is generation of lampblack, such as in a kitchen, etc.
The unit surface may crack or the sensor may malfunction as a result.
FILTER GUIDELINES
•Follow the instructions in this manual for correct care and maintenance of the filters.
This equipment complies with the requirements of Directives
89/336/EEC and 73/23/EEC as amended by 93/68/EEC.

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FU-28H-S
HOW SHARP AIR PURIFIER WORKS
An air purifier draws in room air from its air intake, lets the air pass through an Active Carbon Filter (Deodorizing
Filter) and a HEPA Filter (dust collection filter) inside of the unit, then discharges the air from its air outlet.
The air purifier unit repeats this process by moving its internal fan.
As air passes through, the HEPA Filter can remove dust particles. The Active Carbon Filter gradually absorbs odour
elements as they repeatedly pass through the filter.
(Odour elements are absorbed by HEPA Filter as well.)
Some odour ingredients absorbed by the filters may become separated and may be discharged through the air outlet
and result in additional odour.
Depending on the usage environment, this odour may become strong in a shorter period than expected.
In this case, purchase the optional replacement filter kit FZ-28SEF.
NOTE
The air purifier is designed to remove air-suspended dust and odour, but not harmful gases (for example, carbon
monoxide contained in cigarette smoke). Neither can it completely remove odours that are always present (for
example, odours from construction materials and pet odours).
HEPA Filter
Active Carbon Filter

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FU-28H-S
SPECIFICATIONS FOR THIS PRODUCT
1.Specifications
Type FU-28H-S
Power supply 220 - 240V 50/60Hz
Fan level adjustment Max Silent
Rated power (W) 29 3.1
Fan level (m3 /hour) 168 30
Fan rotation speed (r.p.m.) 1000 ±10 330 ±10
Noise (dB) 46 14
Applicable floor area 1 Around ~ 21m2
Dust collecting method Mechanical purification
Protective devices Current fuse Turning off when abnormal current (2.5A) flows
Control panel Power ON/OFF, Fan control, OFF timer
Operation indicator light Plasmacluster indicator light (blue), Auto, Max, Silent
OFF-Timer 1 hour, 4 hours
Remote control Operation mode Power ON/OFF, Auto, Fan control (manual), OFF-timer
OFF TIMER time 1 hour, 4 hours
Outside dimension (mm) 482 (W) x 142 (D) x 337 (H)
Weight (kg) 6.2
Cord length (m) 2.5
Installation Wall mounting
Accessories HEPA filter, Active carbon filter, remote control , 2 AA batteries, Wall mounting Kit (Wall
mounting braket, Wood screws[4], Fisher plugs[4])
Replace the filter 2 HEPA filter : 12 months
Active carbon filter : 12 months
Option Replace filter : FZ-28SEF (1 HEPA Filter, 1 Active Carbon Filter.)
1: The size of the room to be referred to is the one in which dust concentration of 1.25mg/m3 may be reduced to
0.15mg/m 3within 30 minutes under the condition that the natural ventilation is performed once per hour.
2: Ten cigarettes are smoked per day in the place where the air cleaner is installed.
Reduction of stand-by power consumption
While this product is plugged in, it consumes the stand-by power of approximately 1.0W to activate the electric circuit

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FU-28H-S
2.External dimentions
1) Simple substance figure
482
[Length unit : mm]
337
139.5
2) Wall tapestry figure
9
141.5
337
482
[Length unit : mm]
Wall
Wall
Wall
Wall
Wall
Wall

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FU-28H-S
NAMES OF PARTS
MAIN UNIT DISPLAY
Plasmacluster Indicator Light
Fan Speed Indicator Lights
OFF Timer Display Indicator Lights
Remote Control Receiver
Power ON/OFF button
Fan Control button
OFF Timer button
Odour Sensor
Filter Frame
HEPA Filter (white)
(with Microbial Control Filter)(blue)
Active Carbon Filter
(Deodorizing Filter)
Stainless Steel Pre-Filter
Front Panel
BACK
Power Cord
Adjusting Guide
Power Cord
Power Plug
ACCESSORIES
Remote Control
(1 unit)
Battery
(R6(AA) battery X 2 )
Operation Manual
Wall mounting kit
•Wall mounting bracket
•Wood screws (4 pcs)
•Fisher plugs (4 pcs)
Air Outlet
(Shape of plug
depends on country)

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FU-28H-S
INSTALLATION
FOR APPROPRIATE INSTALLATION
To remove room odour
Installing the unit high up on the wall is most effective.
To remove room dust
Comparatively large dust particles such as pollen and house dust collect in the lower strata of the
room air.
Select a location in the room where the air circulation is good.
This improves the cleaning performance and causes Plasmacluster ions to spread throughout the
room.
Operating Conditions
Please operate the unit under the following conditions.
It is recommended to use the unit in a room where the temperature is in the range of 0 - 35C°.
Avoid locations where the unit is exposed to condensation, due to drastic temperature changes.
Installation Cautions
•Before fixing the wall mounting bracket, make sure there is nothing that could obstruct installation of the unit.
Then fix the wall mounting bracket through screw holes with the supplied wood screws.
•Install the unit on a wall, wooden pillar, crosspiece or the like that is flat and strong enough..
•If the wall is weak or made of concrete, have the unit installed by a specialist such as an electric appliance
store.
•Avoid locations near inverter lamps or where the unit is exposed to direct sunlight.
1
Determine the mounting location
Leave space around the bracket referring to the drawing below. The unit cannot
be mounted if there is insufficient spacing around the bracket.
207mm
337mm (Size of main unit)
48mm
54mm
235mm
482mm ( Size of main unit)
Power cord
330mm
16mm
60mm
3mm
92mm
Wall mounting bracket
Screw Holes
Screw Holes
Size of main unit
70cm or more from
side wall 70cm or more from side wall
Center line of Wall mounting bracket
Center line of main unit
Center line of
main unit
45cm or more from the ceiling

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FU-28H-S
Installation on a
wooden pillar
ø5mm
35mm
Installation on a
wooden crosspiece
Wood screws (4)
Wooden pillar
Caution
•To install the unit on a wooden wall that is less than 10 mm thick, consult your
dealer and have them confirm the strength of the wall before installation.
•Install the unit on a wall, wooden pillar, crosspiece, etc. that is flat and strong
enough.
•Make sure that the unit is installed in an upright position, without leaning to
the right or left.
Wooden crosspiece
Wall mounting bracket
Hole on the wall
Fisher plug
Wood screw
2
Mount wall mounting bracket
•Mount the bracket using the included wood screws so that it is maintained level.
Installation on a concrete, block or mortar surface
Drill holes of at least 35 mm depth and 5 mm diameter into the wall, drive in
Fisher plugs, and fix the unit with wood screws.
Installation on a wooden pillar, crosspiece or other wooden surface
Use wood screws for installation.

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FU-28H-S
Before starting the wall installation, be sure to remove the front panel
and filter frame.
In case the power plug to
be lead to the left of the
unit.
Do not wire the
power cord right
below the wall
mountingbracket.
Power cord adjusting guide
Incasethepowerplug tobe lead
to the right of the unit.
Cautions
•To avoid scratching or damaging the unit, place it on a soft piece of cloth
until it is installed on the wall.
•Do not lead the power cord together with other cord and do not twist it.
•Never modify the power cord.
•Take care not to damage the power cord.
Front Panel Filter Frame
Air Outlet
1
2
3
Install the unit on the wall.
1
Place the unit facing
up, remove the Front
Panel and Filter Frame.
2
Adjust the length of the power cord.
1
Measure the distance between the unit and the wall outlet.
(Refer to E-6)
2 Place the unit face down, and insert the
power cord into the power cord adjust-
ing guide so as to adjust it to the meas-
ured length.
Power Cord
Adjusting Guide

11
FU-28H-S
3
Apply a mark (tape, etc.) 8 cm above both ends of the wall mounting
bracket.
4
Lift up the unit so that the hooking holes on the unit are aligned with
the marks, hook the unit onto the wall mounting bracket and slide it
to the right.
When positioned correctly, the unit will move down slightly until it
engages.
Alignment with the right hooking holes
Alignment with the left hooking holes
5
Double-check the installation.
Make sure that the claws of the unit are hooked in properly. If they are
not, the unit will move sideways. In addition, the unit may fall off the
wall and be damaged.
•Make sure that the power cord is not caught in the unit.
6Remove the mark.
Wall mounting bracket
HOW TO REMOVE THE UNIT
Pull the power plug out of the wall outlet and remove
the Front Panel and Filter Frame. Holding the unit by
its lower corners, lift it up slightly, then slide it to the
right or left and lift it off toward the top.
1
2
2
2
1
mark about 8 cm
claw socket
about 8 cm mark
claw socket

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FU-28H-S
Be sure to remove the filters from the
plastic bags before using the unit.
1
Remove the Pre-Filter,
Active Carbon Filter and
HEPA Filter from the Filter
Frame.
2
Remove theActive Carbon
Filter and HEPA Filter from
the plastic bags.
3
Place the HEPA Filter
within the Filter Frame.
Do not install the filter backwards
orthe unit will not operate properly.
4
Place the Active Carbon
Filter within the Filter
Frame on top of the HEPA
Filter.
The Active Carbon Filter does not
have a front and a back.
5
Next, place the Pre-Filter
within the Filter Frame.
Fit the 4 tabs of the Pre-Filter into
the holes in the Filter Frame.
FILTER INSTALLATION
Tabs
Pre-Filter
Active Carbon Filter
HEPA Filter
Filter Frame
HEPA Filter
Filter Frame
Pre-Filter
Active Carbon Filter
HEPA Filter
Filter Frame
Tabs
How to Remove the Stainless
Steel Pre-Filter
Active Carbon Filter HEPA Filter

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FU-28H-S
6
Mount the Filter Frame to
the main unit.
7
Fill in the usage start date
on the Date Label.
Use the date as a guide for the
Filter Replacement schedule.
8
Mount the Front Panel to
the main unit.
9
Insert the power plug into
the wall outlet and check
on/off operation using
the remote control.
Date Label
Claw socket
Claw
Filter Frame
Front Panel

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FU-28H-S
ABOUT THE FUNCTION
AUTO OPERATION
The air purifier will automatically adjust its speed according to the air quality detected by the odour sensors in order to
clean effectively.
SILENT OPERATION
The air purifier will operate quietly, producing only a slight current of air (the lowest fan speed).
MAX OPERATION
The air purifier will operate at its highest setting. This feature is useful when you want to remove airborne dirt and
contaminants from room air quickly.
OFF TIMER OPERATION
The air purifier will turn itself off after the set amount of time elapses (1 or 4 hours).
PLASMACLUSTER ION OPERATION
While the product is in operation, the unit will constantly dischange approximately the same amount of Positive and
Negative ions. This is effective for reducing some airbone mold.
SAFETY DEVICES
Fuse .....................Operates in the presence of an abnormal current (trip current: 2.5A)

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FU-28H-S
ELECTRIC CIRCUIT
1. ABOUT LEAD-FREE SOLDER
1) Employing lead-free solder
The "Main PWB" of this model employs lead-free solder. This is indicated by the "LF" symbol printed on the PWB
and in the service manual. The suffix letter indicates the alloy type of the solder.
Example:
LFa
Sn-Ag-Cu Indicates lead-free solder of tin, silver and copper.
2) Using lead-free wire solder
When repairing a PWB with the "LF" symbol, only lead-free solder should be used. (Using normal tin/lead alloy solder
may result in cold soldered joints and damage to printed patterns.)
As the melting point of lead-free solder is approximately 40ºC higher than tin/lead alloy solder, it is recommend that
a dedicated bit is used, and that the iron temperature is adjusted accordingly.
3) Soldering
As the melting point of lead-free solder (Sn-Ag-Cu) is higher and has poorer wettability, (flow), to prevent damage
to the land of the PWB, extreme care should be taken not to leave the bit in contact with the PWB for an extended
period of time. Remove the bit as soon as a good flow is achieved. The high content of tin in lead free solder will cause
premature corrosion of the bit. To reduce wear on the bit, reduce the temperature or turn off the iron when it is not
required. Leaving different types of solder on the bit will cause contamination of the different alloys, which will alter
their characteristics, making good soldering more difficult. It will be necessary to clean and replace bits more often
when using lead-free solder. To reduce bit wear, care should be taken to clean the bit thoroughly after each use.
2. WIRING DIAGRAM
(CACCJA031KKEZ)
AC220-240V
(FW-VZA056KKEZ)
(CKITTA020AKKZ)
(CMOT-A021KKEZ)
CLUSTER HARNESS
UNIT
PLASMACLUSTER
POWER SUPPLY
PWB ASS'Y
POWER SUPPLY CORD
ACAC
10P
WH-A
PC1 FM
MOTOR
FAN
CONTROL PWB ASS'Y
PWB ASS'Y
DISPLAY
SWITCH
PWB ASS'Y
WH-B
WH-C
6P
12P
CN-A CN-B
10P 12P
CN-C
6P
PWB ass'y(CPWB-A056KKKZ)= Power supply PWB + Control PWB + Display PWB + Switch PWB

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FU-28H-S
3. PRINTED WIRING BOARD

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FU-28H-S
4. OPERATIONS
(1) Block diagram
Noise preventon
circuit Power supply
circuit
Power supply
clock generation
circuit clock circuit
LED drive
circuit
Fan motor
drive circuit Reset circuit
Key input
circuit
Plasmacluster
unit drive circuit
Remote control
signal receive
circuit
Buzzer drive
circuit EEPROM
circuit
Odour sensor
circuit
LSI-1 (Microcomputer)
1) 2) 3) 5)
10) 9) 13) 8)
11) 4) 7)
12) 6)
(2) Circuit description
1) Noise prevention circuit
This circuit protects the circuit from the external noise and lightning surge coming in from the AC plug, and also
absorbs the noise outgoing from the AC plug. It consists of the film capacitor C1 and C4, varistor VRS1, current
fuse FUSE, and line filter L1.
2) Power supply circuit
a) Vm: The commercial power supply (AC220-240V) is put through the current fuse FUSE, rectified by the
diode bridge DB1, and smoothed by the electrolytic capacitor C2.
Then it is supplied as the power input for the fan motor and the hybrid IC (HIC1).
(Vm = approx. DC311-339V)
b) VL: The hybrid IC (HIC1) is activated by the DC input Vm and the external coil L2, and has two output
terminals.
The first output is changed into VL after being smoothed by the electrolytic capacitor C12.
It is used as the power supply for the buzzer drive circuit, fan motor drive circuit, and plasmacluster
unit drive SSR1 (VL = approx. DC15V).
c) VDD: The second output is smoothed by the electrolytic capacitor C11 before used as the power supply for
the microcomputer LSI-1, plasmacluster unit drive circuit, odour sensor circuit, and LED drive circuit
(VDD = approx. DC5V).
3) Power supply clock generation circuit
The voltage between the input terminal to DB1 and its output terminal (GND) is divided by the resistor R21, R22
and R23, and input into the digital transistor Q21.
Then it is converted into the DC square wave signal that has the same frequency with the AC power supply, and
input into the pin 38 on the microcomputer LSI-1 via the resistor R25 and the ceramic capacitor C22.
The microcomputer LSI-1 considers it as the source signal for time count, and decides the power supply
frequency and controls the output time.
When this signal retains " H " or " L " state for over certain period of time, the microcomputer LSI-1 assumes it to
be a power failure and stops outputs from the fan motor, plasmacluster unit, odour sensor, buzzer, and LED.
4) Reset circuit
If the VDD is lower than specified, " L " is input into the pin 8 of the microcomputer LSI-1 to reset LSI-1 using the
circuit consisting of the reset IC (IC-2), R31 and C32.
When VDD is higher than specified, " H " is input into the same pin, reset command is canceled, and LSI-1 is started.
5) Clock circuit
This generates the clock signal required for operation of the microcomputer LSI-1.
Its frequency is 8MHz which is supplied from the ceramic oscillator CF1.
6) Key input circuit
The key SW1 - SW3 on the switch PWB unit is connected to the resistor R101.
The key status is input into the pin 9 of the microcomputer LSI-1 via the resistor R102 and the ceramic capacitor
C101. Key ON : H, Key OFF : L

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FU-28H-S
7) LED drive circuit
Repetitive signal of " H " and " L " output from the pins 18 - 20 of the microcomputer LSI-1 turns on and off the
digital transistors Q110 - Q112.
They are turned on one by one at intervals of certain time. When " L " is output from the pins 15 - 17 of the
microcomputer LSI-1 as they are turned on, the corresponding LED that are connected to them light up.
And " L " is output from the pin 11 of the microcomputer LSI-1, Q113 is turned on, the plasmacluster LED turned on blue.
8) Remote control receiving circuit
The infrared signal transmitted from the remote controller is received by the reception unit RU1.
When the H/L signal is input into the pin 23 of the microcomputer LSI-1 via the resistor R81 and the ceramic
capacitor C83, it is determined from which key the signal was transmitted. C81, C82, and C83 absorb or reduce
the disturbing lights, noise derived from its own power supply circuit, and external noise.
9) Odour sensor circuit
The pulse signal, which is the odour sensor drive signal, is output from the pin 41 of the microcomputer LSI-1, and
the odour sensor is pulse-driven on the circuit of Q71, Q72, R73, R74, R76, and C73.
The sensor output signal is input into the pin 29 (A/D conversion terminal) of the microcomputer LSI-1 via R71 and C71.
< Principle of odour sensor >
The metal oxide semiconductor in this sensor reacts to ammonia, hydrogen, and alcohol, and changes the
resistance.
Weak odour : high resistance _ high voltage
Strong odour : low resistance _ low voltage
< Control >
After turning the power on, the value obtained 25 seconds after starting the first operation is set as the reference
value and the contamination is decided in relative comparison between the values detected at an interval of
approximately one second and the reference value.
Although the odour sensor is always activated during operation, it is deactivated while the operation is stopped
to cut down the standby power consumption.
However, if it comes to a complete stop, the reading condition is altered in the next operation.
Therefore, it is activated for one minute in every ten minutes to keep the operating conditions.
Reference value : If the current level is cleaner than the reference value
_ the reference value is changed to the current value immediately.
If the current level is dirtier than the reference value and the contamination level changes
(such as suddenly increased odour of cigarette smoke)
_ the reference value remains the same
_ the value in the clean condition is adopted as a new reference value.
If the current level is dirtier than the reference value and the contamination level does not
change (Natural change only)
_ the reference value remains the same.
_ the value in the cleanest condition at eight-minute intervals is adopted as a new
reference value.
10)Buzzer drive circuit
The " H " / " L " signals output from the pin 22 of the microcomputer LSI-1 drive the digital transistor Q51 and
sound the buzzer BZ1.
11)Fan motor drive circuit
The fan motor has four input terminals and one output terminal.
Vm:DC voltage input to be the source of motor rotation. (Vm = approx. DC311-339V)
(FM 7 pin) Vm created by the power supply circuit is directly input and is constantly applied.
GND:Reference of the electric potential. All potentials such as Vm, Vcc, Vs, and PG indicate the
(FM 5 pin) potential differences with GND.
Vcc:DC voltage input terminal to be the power supply for the circuit that is built in the fan motor.
(FM 3 pin) During operation, it turns on Q43 and Q44 by outputting the " H " signal from the pin 21 of the
microcomputer LSI-1, and supplies the potential almost equal to VL to the Vcc terminal (Vcc =
approx. DC15V).
Vs:This input terminal controls the rotation speed of the fan motor (speed instruction signal).
(FM 2 pin) After supplying Vcc during operation, the PWM (x/256µs) pulse is output from the pin 25 of the
microcomputer LSI-1 and smoothed in the circuit consisting of C41, R41-43, Q41 and Q42.
Then it goes through R46 and C43 to supply the DC voltage to the Vs terminal.
(Vs = approx. DC 0 ~ 6V)
When speeding up rotation : the pulse width X is widened _ Vs voltage is increased
When slowing down rotation : the pulse width X is narrowed _ Vs voltage is decreased
PG:Fan motor rotation speed output terminal (feedback signal)
(FM 1 pin) The pulse signal according to the rotation speed is output and it is input into the pin 24 of the
microcomputer LSI-1 via the circuit consisting of R47, R44, R45, and C42.
The microcomputer recognizes the current rotation speed based on this PG signal, and controls
the Vs signal above to keep the speed to the designated level.

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FU-28H-S
12)Plasmacluster unit drive circuit
The plasmacluster unit is the power supply unit that supplies the high voltage to generate ion from the cluster
electrode, and it can be activated by inputting AC220-240V into it.
When the solid state relay SSR1 is turned on, the voltage for commercial power supply drops in the resistor R124
and approximately AC90-110V is applied to the plasmacluster unit.
During operation, it outputs " H " / " L " from the pin 39 of the microcomputer LSI-1, turns on and off Q121, and
controls and drives SSR1.
13)EEPROM circuit
During operation, data integrated with the operation time of the fan motor (dirtiness of the filter) is read and written
into EEPROM (IC-1) using the repetitive signals of " H " and " L " that are input and output from the pins 6 and 7
of the microcomputer LSI-1.
5. TEST MODE
(1) Outline
Test mode is the mode for testing operation of circuit PWB, or sensors and the load output.
(2) Setting method
When turning on the power while pressing the [OFF TIMER button] of the main body, the buzzer sounds "peep"
and enters the "test mode".
(3) Canceling method
In all test modes, when pressing the [POWER ON/OFF button] on the remote controller, the buzzer sounds
"peep" and the "test mode" is canceled and becomes the initial state at normal halt.
(4) Contents
By operating and checking, the check of circuit PWB, sensors, and the load output of operation can be performed
as follows.
PWB ASSEMBLY
Load Output LED
No. Operation Operation mode OFF timer Cluster Buzzer Point to be check
Fan Cluster Odour Auto Max Silent 4 hours 1 hour ion
Silent Max Drive Sensor Green Green Green Green Green Blue
PORT No. 25 39 41 2 3 4 5 6 1 –LED No.
1 Turn the power on while holding down
Model select, memory ON/OFF check
the "OFF TIMER" button on the main unit.
2 Press the "POWER ON/OFF" button
EEPROM version No. [upper side] check
on the main unit.
3 Press the "FAN CONTROL" button
EEPROM version No. [lower side] check
on the main unit.
(High)
4 Press the "OFF TIMER" button
(High)
5 Press the "Auto" button
(High)
6 Press the "Manual" button
Fan motor rotation speed [upper side] check
Check the rotation speed [upper side] of
on the remote controller. the fan motor (Max).
8 Blow gas to the Odour sensor.
9 Power OFF
2) Error display listNo. Concerned item No. Error display, symptom Error contents Probable cause
Reference 1 item 2 Auto lamp flickers, operation impossible EEPROM communication error EEPROM circuit failure, EEPROM failure
2 item 2 Auto lamp lights on, operation impossible EEPROM data error Wrong EEPROM data
3 All items Silent lamp flickers. Fan motor rotation speed error Fan motor circuit failure
Check the version No. of EEPROM.
(Version No. 29 = 00011101)
: ON : Peep sound, : Pip sound
on the main unit.
on the remote controller.
(High)
7 Press the "OFF Timer" button
Fan motor rotation speed [lower side] check
on the remote controller.
1) Check the voltage : VDD = 5V±0.3V
Check the rotation speed [lower side] of
the fan motor (Max).
OK if in the range of ±1 in binary digit.
The "Cluster ion" lamp lights on after
10 seconds has passed from the start of
item 2.
The "Auto" lamp lights on.

20
FU-28H-S
6. ERROR MODES
(1) Outline
Error modes serve as self-diagnostic tools, using a range of sensors to detect errors and failures in the purifier
and its circuitry and indicating the nature of those errors through load operation and error displays.
This air purifier supports two error modes, "EEPROM error" and "fan motor rotation speed error".
(2) EEPROM error
(a)Outline ............................. This error mode is activated when "a communication error" or "a data error" is
detected while loading information stored on the EEPROM at the time of a power
supply injection.
(b)Detection time.................. Immediately after a power supply injection.
(c) Error display..................... Only the "auto lamp" flashes in a one-second cycle. All other LEDs are turned off.
(d)Switch operation .............. All switch operations are invalid.
(e)Loads control ................... All loads turn off. The buzzer does not sound.
(f) Remedy ........................... Please replace the PWB.
(3) Fan motor rotation speed error
(a)Outline ............................. This error mode is activated when the unit detects that the fan motor is locked or
the connector is opened.
(b)Detection time.................. In all modes during operation
(c) Detection conditions ........ When the unit detects [0 rpm] as the rotation speed of the fan motor for 15
consecutive seconds.
(d)Abnormality display.......... Only the "silent lamp" flashes in a one-second cycle. All other LEDs are turned off.
(e)Loads control ................... All loads are turned off immediately and it considers as an operation stop state.
The buzzer does not sound.
(f) Cancellation ..................... The error mode can be cancelled by pressing the "POWER ON / OFF " button on
the main unit or on the remote controller. However, with the problem unsolved, the
unit enters the same error mode even if you turn on the unit again.
(g)Remedy ........................... Please check the insertion of connector on the PWB side.
When you still become unusual, please replace the motor or PWB.