Mitsubishi Electric Fresh Master GUF-100RDH3 User manual

ENGLISH
Contents
1. Safety precautions ............................................ 2-3
1.1. Installation ................................................... 2
1.2. During operation ......................................... 3
1.3. Disposing of the unit ................................... 3
2. Names and functions of various parts ............... 4-6
3. How to operate .................................................. 7-9
3.1. When interlocked with an indoor unit ................. 7
3.2. When not interlocked with an indoor unit ........... 7
3.2.1. Before starting operation ....................... 7
3.2.2. ON/OFF ................................................. 7
3.2.3. Selecting operation ................................ 7
3.2.4. Temperature adjustment ........................ 8
3.2.5. Fan speed adjustment ........................... 8
3.2.6. Time setting ........................................... 8
3.2.7. Timer setting .......................................... 9
4. Cleaning the machine ................................... 10-11
5. Inspection and maintenance
(GUF-50-100RDH3 only) .............................. 11-13
6. Troubleshooting ................................................. 13
7. Installation and transferring works, and checking .... 14
8. Specifications ..................................................... 14
Fresh Master
Models:
GUF-50RDH3 •GUF-50RD3
GUF-100RDH3 •GUF-100RD3
Operating Instructions
(For the user)
For use with the R410A & R407C & R22
Please read through these instructions in order to famil-
iarize yourself with the proper and safe procedures for
operating the Fresh Master.
After reading this manual, keep it in an easily accessible
and safe place for future reference.
The warranty will not apply to damage resulting
from failure to follow the warnings and precau-
tions included in the Operating Instructions.
GUF-50RDH3 shown above.
Humidifier function not available on GUF-50RD3 and
GUF-100RD3.

2
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1. Safety precautions
3) Remote controller
Warning:
The Remote controller should be installed in such a way that chil-
dren cannot play with it.
4) Drain hose
Caution:
Make sure that the drain hose is installed so that drainage can go
ahead smoothly. Incorrect installation may result in water leak-
age, causing damage to furniture.
5) Power Supply, fuse or circuit breaker
Warning:
• Make sure that the unit is powered by a dedicated power supply.
Other appliances connected to the same power supply could
cause an overload.
• Make sure that there is a mains power switch.
• Be sure to adhere to the unit’s voltage and fuse or circuit
breaker ratings. Never use a cable or a fuse with a higher rat-
ing than the one specified.
6) Grounding
Caution:
• The unit must be properly grounded. Never connect the
grounding wire to a gas pipe, water pipe, lightning conductor
or telephone grounding wire. If the unit is not grounded prop-
erly, electric shock may result.
• Check frequently that the ground wire from the outdoor unit is
properly connected to both the unit’s ground terminal and the
grounding electrode.
ss
ss
sBefore operating the unit, make sure you read all the
“Safety precautions”.
ss
ss
s“Safety precautions” lists important points about
safety. Please be sure to follow them.
Symbols used in the text
Warning:
Describes precautions that should be observed to avoid the risk
of injury or death to the user.
Caution:
Describes precautions that should be observed to prevent dam-
age to the unit.
Symbols used in the illustrations
: Indicates that important instructions must be followed.
: Indicates a part which must be grounded.
: Beware of electric shock. (This symbol is displayed on the main
unit label.) <Colour: Yellow>
Warning:
Carefully read the labels affixed to the main unit.
1.1. Installation
ss
ss
sAfter you have read this manual, keep it and the Installation
Manual in a safe place for easy reference whenever a question
arises. If the unit is going to be operated by another person,
make sure that this manual is given to him or her.
Warning:
• The unit should not be installed by the user. Ask the dealer or
an authorized company to install the unit. If the unit is installed
improperly, water leakage, electric shock or fire may result.
• Use only accessories authorized by Mitsubishi Electric and
ask your dealer or an authorized company to install them. If
accessories are installed improperly, water leakage, electric
shock or fire may result.
• The Installation Manual details the suggested installation
method. Any structural alteration necessary for installation
must comply with local building code requirements.
• Never repair the unit or transfer it to another site by yourself.
If repair is performed improperly, water leakage, electric shock
or fire may result. If you need to have the unit repaired or
moved, consult your dealer.
1) Outdoor unit
Warning:
• The outdoor unit must be installed on a stable, level surface,
in a place where there is no accumulation of snow, leaves or
rubbish.
•Do not stand on, or place any items on the unit. You may fall
down or the item may fall, causing injury.
Caution:
The outdoor unit should be installed in a location where air and
noise emitted by the unit will not disturb the neighbours.
2) Fresh Master
Warning:
The Fresh Master should be securely installed. If the unit is loosely
mounted, it may fall, causing injury.

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1.2. During operation
Caution:
• Do not use any sharp object to push the buttons, as this may
damage the Remote controller.
• Do not twist or tug on the Remote controller cord as this may
damage the Remote controller and cause malfunction.
• Never remove the upper case of the Remote controller. It is
dangerous to remove the upper case of the Remote controller
and touch the printed circuit boards inside. Doing so can re-
sult in fire and failure.
• Never wipe the Remote controller with benzene, thinner, chemi-
cal rags, etc. Doing so can result in discoloration and failure.
To remove heavy stains, soak a cloth in neutral detergent mixed
with water, wring it out thoroughly, wipe the stains off, and
wipe again with a dry cloth.
• Never block or cover the Fresh Master or outdoor unit intakes
or outlets. Tall items of furniture underneath the Fresh Master,
or bulky items such as large boxes placed close to the out-
door unit will reduce the unit’s efficiency.
Warning:
• Do not splash water over the unit and do not touch the unit
with wet hands. An electric shock may result.
• Do not spray combustible gas close to the unit. Fire may re-
sult.
• Do not place a gas heater or any other open-flame appliance
where it will be exposed to the air discharged from the unit.
Incomplete combustion may result.
Warning:
• Do not remove the front panel or the fan guard from the out-
door unit when it is running. You could be injured if you touch
rotating, hot or high-voltage parts.
• Never insert fingers, sticks etc. into the intakes or outlets, oth-
erwise injury may result, since the fan inside the unit rotates
at high speed. Exercise particular care when children are
present.
• If you detect odd smells, stop using the unit, turn off the power
switch and consult your dealer. Otherwise, a breakdown, elec-
tric shock or fire may result.
• When you notice exceptionally abnormal noise or vibration,
stop operation, turn off the power switch, and contact your
dealer.
• Do not leave handicapped people or infants sitting or stand-
ing in the path of the airflow from the Fresh Master. This could
cause health problems.
Caution:
• Do not direct the airflow at plants or caged pets.
In case of failure
Warning:
• Never remodel the Fresh Master. Consult your dealer for any
repair service. Improper repair work can result in water leak-
age, electric shock, fire, etc.
• If the Remote controller displays an error indication, the Fresh
Master does not run, or there is an abnormality, stop opera-
tion and contact your dealer. Leaving the unit as it is under
such conditions can result in fire or failure.
• If the power breaker is frequently activated, get in touch with
your dealer. Leaving it as it is can result in fire or failure.
• If the refrigeration gas blows out or leaks, stop the operation
of the Fresh Master, thoroughly ventilate the room, and con-
tact your dealer. Leaving the unit as it is can result in acci-
dents due to oxygen deficiency.
When the Fresh Master is not to be used for a
long time
• If the Fresh Master is not to be used for a long time due to a
seasonal change, etc., run it for 4 - 5 hours with the air blow-
ing until the inside is completely dry. Failing to do so can re-
sult in the growth of unhygienic, unhealthy mold in scattered
areas throughout the room.
• When it is not to be used for an extended time, keep the power
supply turned OFF.
• If the power supply is kept on, several watts or several tens of
watts will be wasted. Also, the accumulation of dust, etc., can
result in fire.
• Keep the power switched ON for more than 12 hours before
starting operation. Do not turn the power supply OFF during
seasons of heavy use. Doing so can result in failure.
1.3. Disposing of the unit
Warning:
When you need to dispose of the unit, consult your dealer. If pipes
are removed incorrectly, refrigerant (fluorocarbon gas) may blow
out and come into contact with your skin, causing injury. Releas-
ing refrigerant into the atmosphere also damages the environ-
ment.

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2. Names and functions of various parts
Fresh Master
The Fresh Master supplies clean air that is close to the indoor temperature and humidity by using the Lossnay ventilation function and the direct
expansion-coil air conditioning function The Fresh Master uses the high efficiency filter for dust removal and permeable-film humidifier to create a
pleasant indoor environment.
Outdoor unit
Outdoor units differ according to systems and can sometimes be in
configuration other than those described in this manual.
Caution:
Carry out grounding work. Never connect the grounding wire to a
gas pipe, water pipe, arrester, or telephone grounding wire. Im-
proper grounding work can result in electric shock.
Lossnay core
Temperature and humidity are
exchanged between supply air
and exhaust air.
High efficiency filters (Optional parts)
Removes dust from the outside air.
Damper plate
Switches between the Lossnay ventilation
and normal ventilation.
Air filter
Prevents clogs in the Lossnay core
Remote controller
• Check out your remote controller. Different controllers are used for
different systems.
* If you open the door, the name of the Remote controller is shown at
the lower left.
Remote controller
[PAR-20MAA]
[PAR-F27MEA]
(Diagram of a controller with the door open.)
(Diagram of a controller with the door closed)
Grounding conductor
Air outlet
Front panel (service panel)
Air inlet
Display section
Operation section
*GUF-50RDH3 shown above.
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
Control box
Maintenance cover
Ceiling suspension fixture
Exhaust fan
Fan used to expel dirty air to outside of the room
Direct expansion coil
Heats or cools the air supply after heat exchange.
Electronic expansion valve
Maintenance cover (for humidifying)
Permeable-film humidifier
Performs clean humidifying of the air supply
after heat exchange.
Not available on GUF-50 and 100RD3
Discharge valve
Drain discharge hole
Service valve
Strainer (O-ring installed)
Air supply fan
Fan to supply outside air to the inside
Water supply tube
Supplies water to the permeable-film humidifier.
Duct connection flange

5
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Wiring diagrams
When interlocked with an indoor unit. When not interlocked with an indoor unit.
Transmission line
Remote controller (PAR-20MAA)
(PAR-F27MEA)
Transmission line
Remote controller (PAR-20MAA)
(PAR-F27MEA)
Fresh Master
Indoor Unit
Fresh Master
Operation section
PAR-F27MEA
ON/OFF
CENTRALLY CONTROLLED
DAILY
AUTO OFF
REMAINDER
ERROR CODE
CLOCK
ON OFF
˚C
CHECK MODE
FILTER
TEST RUN
LIMIT TEMP.
˚C
1Hr.
NOT AVAILABLE
STAND BY
DEFROST
FILTER
CHECK TEST
TEMP.
TIMER SET
CLOCK→ON→OFF
CHECK
1[ON/OFF] Button
After natives between run and stop every time it is pressed. The lamp on
the button stays lit during operation.
2[Ventilation] Button *
Used when switching the ventilation of the Fresh Master between Stop,
Low and High.
3[Fan speed adjustment] Button
Used to switch the fan speed between high and low.
4[Time selection] Button
Used to switch between the current time, starting time, and ending time.
5[Time-setting] Button
Used to set the current time, starting time, and ending time.
6[Timer] Button
Used to switch between continuous operation and timer operation.
* When interlocked only.
7[Selecting operation] Button
Used to switch between cooling, fan, and heating.
8[Temperature adjustment] Button
Used to set the temperature.
Setting is made in units of 1°C.
Every time is pressed, the temperature goes up by 1°C.
Every time is pressed, the temperature goes down by 1°C.
9[Checking/test run] Button
Used only during checking test run. Never use this button during normal
operation.
0[Filter] Button
Pressed to reset the filter sign.
1
235
4
6
7
8
0
Open the door.
9

6
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Display section
PAR-F27MEA
ON/OFF
CENTRALLY CONTROLLED
DAILY
AUTO OFF
REMAINDER
ERROR CODE
CLOCK
ON OFF
˚C
CHECK MODE
FILTER
TEST RUN
LIMIT TEMP.
˚C
1Hr.
NOT AVAILABLE
STAND BY
DEFROST
FILTER
CHECK TEST
TEMP.
TIMER SET
CLOCK→ON→OFF
CHECK
For purposes of explanation, all the displays on this page are shown
in their lit condition. This configuration does not occur in the actual
unit.
A[Current/starting/ending time] Display
When the time switch button is pressed, the current time, starting time
and ending time are displayed for 10 seconds. During timer operation,
the next starting time or ending time is always displayed.
B[Centralized control] Display
Displayed when control is executed by a separately sold centralized con-
trol unit, etc.
C[Timer] Display
This displays the modes of continuous operation/timer operation. Time
is simultaneously displayed at the time of timer operation.
DOperation mode
Displays the status of operation.
E[Preparing for Heating] Display
Displayed from the start of heating operation until the moment warm air
blows out.
F[Defrosting] Display
Displayed during defrosting operation.
G[Checking] Display
This displays indication when an abnormality occurs in the unit.
H[Set temperature] Display
Displays the set temperature.
I[Address numbers of indoor unit/unit in linked motion] Display
Displayed when some abnormality occurs in the unit.
J[Error number] Display
Displays the (4-digit) checking code when an abnormality occurs in the
unit.
KDisplay “'”
Displayed while the air conditioner is powered.
L[Louver operation] Display
This displays the operation of a swing louver. This does not display in
case of stop.
M[Not available] Display
When a button is pressed for any function that the indoor unit cannot
perform, this display flashes concurrently with the display of that func-
tion.
N[Ventilation] Display *
Displayed during the Fresh Master’s operation.
O[Position of built-in room temperature sensor]
P[Set effective for one hour] Display
Displays when the low air blow, downward blow, or horizontal blow (dif-
fers according to model) are set in the air-cooling and electronics dry
operation. This display disappears after the elapse of one hour.
Q[Now checking/test run] Display
R[Filter] Display
Displayed when it is time to clean the filter.
S[Sensor] Display
Shows a position of the sensor that measures the room temperature.
T[Operation] Lamp
Lights up during operation, goes off during stop, and flashes in case of
abnormality.
U[Room temperature] Display
Displays the temperature of the air sucked in during operation. The range
of display is 8°to 39°C. For temperatures outside this range, the display
flashes at 8°C and 39°C.
[Up/down airflow direction] Display
Displays the air blowout direction with a smark.
W[Fan speed] Display
Displays the selected fan speed.
* When interlocked only.
ABC W U
S
R
Q
P
ONMLTKJI
H
G
F
E
D

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3. How to operate
3.1. When interlocked with an indoor
unit
•Operation will be synchronized with an indoor unit.
•The humidifier will be operated by the heating signal received from
the indoor unit. (For GUF-50, 100RDH3)
•In the case of GUF-50, 100RDH3, there is no temperature control
since the temperature is adjusted according to the outside air tem-
perature.
Starting and stopping operation
•Using the Remote controller to start or stop the indoor unit will au-
tomatically start or stop the Fresh Master.
Operation modes
•The Fresh Master will operate in the same mode as the synchro-
nized indoor unit (heat, cool and fan).
•The Fresh Master will be cool when the indoor unit is operated in
dry mode.
When using with multiple indoor units
• When using with multiple indoor units that are set differently, the Fresh
Master will operate in the mode with priority of: heat, cool and fan.
When operating only the Fresh Master
•The Fresh Master can be operated independently by pressing the
Ventilation button on the Remote controller (in this case, the opera-
tion mode will be fan).
•Pressing the Ventilation button each time will switch the display
between Stop, Low and High.
3.2. When not interlocked with an
indoor unit
•GUF-50, 100RD3 will adjust the temperature according to the in-
door temperature set using the Remote controller.
• In the case of GUF-50, 100RDH3, there is no temperature control since
the temperature is adjusted according to the outside air temperature.
3.2.1. Before starting operation
•Make sure that the power supply is turned ON before use.
(Keep the power supply turned ON at all times when the Fresh Master is
in use. Use of the unit without power can result in compressor failure.)
•Start running after the “HO”display has disappeared. The “HO”
display briefly appears on the room temperature display (max. 10
minutes) when the power is turned on and after a power failure.
This does not indicate any failure of the Fresh Master.
•The operation modes of the Fresh Master air-cooling operation and
heating operation are different from those of the outdoor units.
When the operation is started with cooling/heating and other in-
door units or the Fresh Master connected to the counterpart out-
door units are already running in the same operation mode, the
Remote controller displays air-cooling/heating mode. However, the
operation comes to stop, and you cannot get a desired mode. When
this occurs, you will be notified by the “cool”or “heating”display
that flashes in the liquid crystal display of the Remote controller.
Set to the operation mode of other indoor unit or the Fresh Master
by the operation switch button.
The above does not apply to the models that simultaneously run
both the cooling operation and heating operation.
•The outdoor units stop when all the indoor units and the Fresh
Master connected to the counterpart outdoor units stop.
• During heating operation, even if the indoor unit or the Fresh Master is
set to operation while the outdoor unit is in defrosting operation, opera-
tion starts after the defrosting operation of the outdoor unit has ended.
Warning:
Check and confirm the power circuit before use. For contents,
refer to the previously described chapter [Crucial points to be
observed for safety].
3.2.2 ON/OFF
PAR-F27MEA
ON/OFF
˚C
˚C
FILTER
CHECK TEST
TEMP.
TIMER SET
CLOCK→ON→OFF
Start an operation
Press [ON/OFF] button
Operation lamp lights up and operation starts.
Stop an operation
Press the [ON/OFF] button again
Operation lamp goes off and operation stops.
•Once the buttons have been set, pressing of the [ON/OFF] button
only can repeat the same operation thereafter.
•During operation, the operation lamp above the [ON/OFF] button
lights up.
Caution:
Even if the operation button is pressed immediately after the op-
eration has stopped, operation will not restart for about 3 min-
utes. This function protects the machine. It automatically starts
operation after approximately 3 minutes.
3.2.3. Selecting operation
PAR-F27MEA
ON/OFF
˚C
˚C
FILTER
CHECK TEST
TEMP.
TIMER SET
CLOCK→ON→OFF
When selecting operation
Press the [selecting operation] button
•Consecutive press of the selecting operation button switches the
operation over to “cooling,”“fan,”“(automatic),”and “heating.”For
the contents of operation, check the display.
For cooling
Press the [selecting operation] button and bring up the “cooling”
display
Stop Low High
Operation lamp
[ON/OFF] button
Operation mode
[selecting operation]
button

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3.2.5. Fan speed adjustment
PAR-F27MEA
ON/OFF
˚C
˚C
FILTER
CHECK TEST
TEMP.
TIMER SET
CLOCK→ON→OFF
To change fan speed
Set the desired fan speed
Every time you press the [fan speed] button once, it switches from the
low-speed or high-speed settings altenatively.
Display of the Remote controller
Low High
* Every time the fan speed adjustment button is once pressed, the
fan speed is changed.
3.2.6. Time setting
PAR-F27MEA
ON/OFF
CLOCK
OFF
˚C
˚C
FILTER
CHECK TEST
TEMP.
TIMER SET
CLOCK→ON→OFF
•Set the current time after turning ON the power of the Fresh Master
or after restoration from a power failure.
•It can be set regardless of the operation of the Fresh Master.
•During the time operation, the time-setting button becomes void,
disabling time setting.
Press the [time selection] button and bring up the “current time”
display
•Every time it is pressed, the display changes.
Caution:
When the current time is not yet set, the “current” time display
flashes, disabling the setting of timer operation.
Set the current time by pressing the time setting or
button
•The time cannot be set while the “[timer]”is displayed.
•While the “CLOCK”time is displayed, press the time setting /
buttons and set the time.
Caution:
Never expose your body directly to cool air for a long time. Ex-
cessive exposure to cool air is bad for your health, and should
therefore be avoided.
For fan
Press the [selecting operation] button and bring up the “fan” dis-
play.
•The fan operation functions to ventilate.
•The temperature of the room cannot be set by fan operation.
For heating
Press the [selecting operation] button to bring up the “heating”
display.
Regarding displays during heating operation “Under defrosting”
Displayed only during the defrosting operation.
“Under preparation for heating”
Displayed from the start of heating operation until the moment warm
air blows out.
•When in the “heating”mode, the humidifier will also operate. (For
GUF-50, 100RDH3)
Caution:
• When the Fresh Master is used together with burners.
• Never place a burner at a place where it is exposed to the air-
flow from the Fresh Master.
Doing so can result in imperfect combustion of the burner.
• The microcomputer functions in the following cases:
The intake fan is not moving at the set speed.
Intake fan stops to prevent any cool air from escaping during
the defrosting operation.
3.2.4. Temperature adjustment
GUF-50, 100RDH3 are OA processing unit and cannot adjust the in-
door temperature, even if the procedures given below are followed.
In the case of GUF-50, 100RD3, the indoor temperature can be ad-
justed.
PAR-F27MEA
ON/OFF
˚C
˚C
FILTER
CHECK TEST
TEMP.
TIMER SET
CLOCK→ON→OFF
To change temperature
Press the temperature button and set the temperature of your
choice
Pressing or once changes the setting by 1°C.
If the pressing is continued, the setting continues to change by 1°C.
•Indoor temperature can be set within the following range.
Cooling/dry 19 to 30°C
Heating 17 to 28°C
•It is impossible to set the temperature in fan operation.
* The range of temperature display is 8°to 39°C. Outside this range,
the display flashes either 8°to 39°C to inform you if the tempera-
ture is lower or higher than the displayed temperature.
(no display)
“current”
time
“start”
time
“end”
time
Set temperature display Room temperature display
[temperature] button
Current time display Time display
[time selection]
button
[time setting]
button
[timer] button
Fan speed
display
[fan speed]
button
In the case of GUF-50, 100RDH3,
set the temperature the same as
the indoor unit.

9
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•The setting advances one minute every time the button is
pressed, and goes back one minute every time the button is
pressed.
When respective /buttons are pressed continuously, the
time display goes fast forward. It advances in the order of 1 minute
digit - 10 minute digit - one hour digit.
•About 10 seconds after the button operation has been completed,
the “current time”and “time”displays disappear.
Caution:
• The Remote controller is equipped with a simplified clock with
a precision of about + or - one minute per month.
• The time must be readjusted (reset) every time the Fresh Mas-
ter is subjected to a power stop or a power failure.
3.2.7. Timer setting
•If the timer is set, the unit starts (stops) at the set time, and the time
mode is terminated.
•When you wish to confirm the starting and ending time, press the
[time selection] button while [timer] is displayed.
Function of timer
On-timer
Set the on-timer for the time the working day begins in your company.
When the set start time arrives, the Fresh Master starts operation.
Off-timer
Use the off-timer as a reminder to turn off the Fresh Master. When the
set end-work time arrives, the Fresh Master stops operation.
There are three methods for using the timer.
1. ON/OFF Timer When setting both starting and ending time
2. On-timer When only setting the starting time
(Ending time is set to “__ : __ ”)
3. Off-timer When only setting the ending time
(Starting time is set to “__ : __ ”)
Display example of timer setting
ON OFF
ON OFF
The example shows a timer set for operation start at 8:00 and end at 17:00.
PAR-F27MEA
ON/OFF
CLOCK
OFF
˚C
˚C
FILTER
CHECK TEST
TEMP.
TIMER SET
CLOCK→ON→OFF
1 Press the [timer] button and erase the “timer” display
2 Press the [time selection] button and bring up the “starting
time” display
3 Press the () button of the [time setting] and set the
starting time
When using it as an off-timer, set the starting time to “__ : __ ”.
The “__ : __ ”is displayed next to the time i.e. 23:50.
4 Press the [time selection] button and bring up the “ending time”
display
5 Press the () button of the [time setting] and set the
ending time
When using it as an on-timer, set the ending time to “__ : __ ”.
The “__ : __ ”is displayed next to the time i.e. 23:50.
6 Press the [timer] button and bring up the “timer” display
Bringing up the [timer] display completes the setting.
Every time the () button of the [timer setting] is pressed
once, it advances (or goes back) by 10 minutes.
If the button is pressed continuously, it advances (or goes back) con-
tinuously.
First set the hour digit and then set the minute digit.
When the ON/OFF timer mode is set, you can run (on-timer) or stop
(off-timer) operation by pressing the [ON/OFF] button even when there
is remaining time.
Release
Press the [timer] button and erase the “timer” display.
[Timer] display [Starting/ending time] display
[Time selection] button
[Timer] button
[Time setting] button

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4. Cleaning the machine
To prevent decline in the Lossnay performance, clean the air filter and
Lossnay core, as well as replace the high efficiency filters.
(Air filter: clean at least once a year)
(Lossnay core: clean at least once every 2 years)
(High efficiency filters: replace every 3,000 hours (approx.))
Caution:
• Before you start cleaning, stop operation and turn OFF the
power supply. Remember that the fan is rotating inside at high
speed, posing a serious risk of injury.
• Always wear gloves when cleaning the unit.
• Maintenance work should only be performed by someone who
has received the necessary training.
1. How to remove each part
(1) Remove the screw (one piece) left side of the Maintenance cover.
(2) Pull back the hinges, open the Maintenance cover and disengage
the cover from the catches.
Caution: The Maintenance cover must be removed.
(3) Draw out the air filters which are located at the bottom left and right
of the Lossnay cores.
(4) Remove the high efficiency filters (Optional parts) from the upper
right side of the Lossnay cores (2 units).
(5) Take hold of the handle and draw the Lossnay cores out from the
main unit. (2 Lossnay cores)
2. How to clean
(1) Air filters
•Use a vacuum cleaner to suck up the dust. To remove stubborn
dirt, dissolve some neutral detergent in cold or lukewarm water,
wash the filters by pressing on them in the water, take them out
and leave them to dry.
Caution:
•Never wash the filters in very hot water of 40˚C or hotter and never
wash them by rubbing them.
•Do not dry the filters by exposing them to a flame.
Air filters
High efficiency filters
(Optional part)
Lossnay cores
Main unit
Air filter
Vacuum cleaner
Catch
Maintenance cover
Screw

11
ENGLISH
(2) Lossnay core
Use a vacuum cleaner to suck up the dust and dirt on the exposed
surfaces of the Lossnay cores. Attach a nozzle with a brush to the
vacuum cleaner for this job, and clean the cores by passing the
brush lightly over their exposed surfaces.
DO NOT WASH IN WATER
Caution:
•Do not use the hard nozzle of the vacuum cleaner.
If may damage the exposed surfaces of the Lossnay cores.
•Under no circumstances should the Lossnay cores be washed in
water.
(3) High efficiency filters (Optional parts)
The high efficiency filters cannot be reused. Always replace with
new filters. For details, consult your dealer.
3. Assembly after cleaning
Bearing in mind the following points, assemble the parts following the
sequence for their removal in reverse.
•Install the air filters so that they are on the Lossnay core side.
•When installing the air filters, take care not to damage the exposed
surfaces of the Lossnay cores.
Lossnay core
Lossnay core
Vacuum cleaner
(with brush attachment)
Corner
5. Inspection and Maintenance
If the unit is to be used for prolonged periods of time, please have the following items inspected by an authorized service office at intervals of about
once a year.
Be sure to turn off the breaker of the distribution board before conducting maintenance or inspection.
Part to be inspected
Strainer
Humidifying elements
Inspection item
Inspect for dust clogging.
Inspect for cracks in O-rings.
Inspect for water leakage from the
surface of each of humidifying
element.
Inspect for dust and particles on the
surface of each humidifying
element.
Action to take
Remove and clean the dust if clogged.
Replace the O-rings if cracked. *Note 1
Replace the humidifying element if water
spurts from its surface. *Note 2
If the air pathway is covered by dust or
particles, carefully clean it using a vacuum
cleaner, or wash it with water by referring to the
cleaning procedure on page 12.
Possible consequence if
maintenance is not
conducted
Unable to humidify
Water leakage
Water leakage
Reduced airflow
Reduced humidifying
power
Description of maintenance and inspection
* Note 1: Replacement O-rings: Commercially available O-rings P22A and P20
* Note 2: A small amount of water may form through dew condensation, but it is not abnormal.
Preparation before cleaning
1. Close the service valve to prevent residual water from spatter-
ing.
2. Take a countermeasure against water leakage.
●Water inside the humidifying elements will leak. Place a vinyl
sheet in the ceiling or take another countermeasure to prevent
water leakage.
3. Drain the residual water from the pipe.
●Place a bucket or other container under the discharge valve
and open the valve to collect the residual water in the pipe.
4. Remove the maintenance cover (for humidifying).
●Remove the seven mounting screws, slide the maintenance
cover to the right, and remove it from the potbelly-shaped holes
(six locations for the GUF-50RDH3).
Mounting screw
Maintenance cover
(for humidifying)
Drain pipe
Discharge valve Service valve

12
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How to clean the strainer (filter)
1. Rotate the strainer cap anticlockwise and remove it.
2. Use water to wash off any dirt adhering to the filter.
3. Replace the strainer cap.
How to remove the humidifying elements
The heat exchanger is located on the left side, and the hanging bolt is
located on the right side. Swing the rear side of each of the humidify-
ing elements to the right, and take out the humidifying element while
making sure not to touch the heat exchanger or the hanging bolt.
1. Remove the inner lid.
1. Place your fingers on the grip part and pull the inner lid for-
ward.
2. Holding both ends with your hands, pull the inner lid forward.
2. Remove the water supply tube from the hu-
midifying element.
Holding the hose bands indicated by [1] to [6] with your fingers,
remove the water supply tubes. Referring to the procedure enti-
tled “removing the humidifying elements” below, remove the water
supply tube at the rear while taking out the front humidifying ele-
ment.
O-ring (P22A)
Strainer
Filter
Strainer cap
O-ring (P20)
Inner lid Grip part
Caution:
• To remove the water supply tube, hold and slide the hose bands
and remove the water supply tube.
• Do not remove the water supply tube from the solenoid valve
unit with a pressure regulator.
• When removing the water supply tube, be sure that water is
collected on the drain tray inside the main unit.
3. Removing the humidifying elements
1. Pull the first humidifying element forward, swing the rear side
of the humidifying element to the right, lift it upward, and then
pull it out diagonally.
2. For the third and subsequent humidifying elements, pull the
rod for removal of the humidifying elements forward until you
can reach an element with your hands, and then pull it out
(GUF-100RDH3).
Caution:
• Do not separate the rod for removal of the humidifying ele-
ments from the product.
• Take out the water supply tube together with the humidifying
element. (Collect the residual water in the humidifying element
using the drain tray.)
• Do not bend or stretch the water supply tubes.
How to wash the humidifying elements
with water
Fill a bucket or other container with water, then shake each hu-
midifying element four to five times up and down in the water to
wash out any dust and particles.
Caution:
• Do not use a scrub brush to clean the humidifying elements.
• Do not hose off the humidifying elements. Doing do so will
damage them.
• Do not use hot water of 40°C or hotter, nor use detergents, to
clean the humidifying elements.
Hose band
Water supply tube
Solenoid valve unit with
pressure regulator
Humidifying
element
Water supply tube
[1]
[2]
[3]
[4]
[5]
[6]
Humidifying element
Model name
GUF-50RDH3
GUF-100RDH3
Quantity
2
4
Humidifying element
Rod for removal of the
humidifying elements
Scrub brush
Hose

13
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6. Troubleshooting
Before you ask for repair service, check the following points:
State of Machine
It does not run.
Cool air or warm air
does not come out.
It runs briefly, but
soon stops.
Do not humidify
(GUF-50,
100RDH3 only)
Troubleshooting
Press the [ON/OFF] button after power restora-
tion.
Turn the power supply ON.
Replace fuse.
Put in the earth leakage breaker.
Wait for a while.
(To protect the compressor, a 3-minute restart-
preventing circuit is built into the Fresh Master.
Therefore, there are occasions sometimes when
the compressor does not start running immedi-
ately. There are cases when it does not run for
as long as 3 minutes.)
Wait for a while.
(Heating operation starts after ending defrosting
operation.)
Rerun after removal
Rerun after cleaning the filters. (Refer to page 10
[Cleaning for the machine].)
Set to the “heating”mode.
Open the service valve.
Cause
Power failure
The power supply is turned OFF.
The fuse in the power supply is gone.
The earth leakage breaker is gone.
The restart-preventing circuit is in operation
for 3 minutes.
Fresh Master operation is started during the
heating and defrosting operation.
There are some obstacles at the air inlet and
outlet of the Fresh Master and outdoor unit.
The filters are filled with dust and dirt.
The Fresh Master is not set to the “heating”
mode.
Water is not supplied.
Remote Controller
“'”display is not lit up
No display appears
even when the [ON/
OFF] button is
pressed.
The liquid crystal
display shows that it
is in operation.
The “check”and
check code flashes
on the liquid crystal
display.
–––
•If operation stops due to a power failure, the [restart-preventing circuit at power failure] functions and disables operation, even after power
restoration. In this case, press the [ON/OFF] button again and start operation.
If malfunctions persist after you have checked the above, turn the power supply OFF and contact your dealer with information about the product
name, the nature of the malfunction, etc. If the display of “[check]”and (4 digit) check code flashes, tell the dealer contents of the display (check
code). Never attempt to repair by yourself.
The following symptoms are not the Fresh Master failures:
•The air blown out from the Fresh Master can sometimes give off odours. This is due to cigarette smoke contained in the air of the room, the smell
of cosmetics, the walls, furniture, etc., absorbed in the Fresh Master.
•A hissing noise can be heard immediately after the Fresh Master is started or stopped. This is the sound of the refrigeration flowing inside the
Fresh Master. The problem is insignificant.
•The Fresh Master sometimes snaps or clicks at the beginning or end of cooling/heating operation. This is the sound of friction on the metal
sections due to inflation and contraction caused by temperature change. The problem is insignificant.
•It is recommended that the air blown out from the Fresh Master be directed to the air conditioner first and then directed into the room. However,
the air may be directed from the Fresh Master to the room without going through the air conditioner. In this air-blowing method, cold air blows out
during heating operation in the cases listed below. In that case, please change the air-blowing method.
•At the start of an operation
•When an operation is restarted immediately after an operation has been stopped (within 3 minutes)
•During a defrosting operation of the outdoor unit
How to install the humidifying elements
Install the humidifying elements in the reverse order of their re-
moval.
●For the GUF-100RDH3, return the rod for removal of the humidify-
ing elements to its original position, and then insert the humidifying
elements.
●Securely connect the water supply tubes and make sure there is
no water leakage.
Rod for removal of the
humidifying elements
(original position)
Check after inspection
1. Open the service valve as necessary.
●Since humidification is not needed during the summer, it is rec-
ommended that the service valve be closed.
2. During the winter, the season requiring humidification, make
sure that the power to the heater for prevention of freezing is
on.
3. Conduct a test and confirm that there is no water leakage.

14
ENGLISH
8. Specifications
GUF-
50RDH3
GUF-
100RDH3
GUF-
50RD3
GUF-
100RD3
Single-
phase
220-240
50
1.15
2.20
1.15
2.20
235-265
480-505
235-265
480-505
m3/h
500
1,000
500
1,000
L/S
139
278
139
278
5.29
(1.66)
10.81
(3.49)
5.29
(1.66)
10.81
(3.49)
6.42
(2.25)
13.00
(4.70)
6.42
(2.25)
13.00
(4.70)
2.70
5.40
–
–
33.5-34.5
38-39
33.5-34.5
38-39
•The values given in the table for the noise level reflect the levels measured at a position 1.5 meters immediately below the unit in an anechoic
chamber.
•The noise at the air outlets (at a 45°angle, 1.5 meters in front) is about 5-6 dB (A) higher than the values given in the table.
•The above values apply during Lossnay ventilation when the fan speed is set to high speed.
* Capacity in ( ) is heat recovery capacity by Lossnay core.
Cooling/Heating capacity indicates the maximum value at operation under the following condition.
Cooling: Indoor: 27°C DB/19.5°C WB Outdoor: 35°C DB/24°C WB
Heating: Indoor: 21°C DB/14.6°C WB Outdoor: 7°C DB/6°C WB
57
98
54
92
Air
volume
External air load heat
processing capability (kw)
Heating
capability
P32
P63
P32
P63
Cooling
capability
Humidifying
volume
Model
name
Power
supply
(V)
Frequency
(Hz)
Current
(A)
Power
con-
sumption
(W)
Noise
(dB)
Weight
(kg)
Equivalent
indoor unit
capability
7. Installation and transferring works, and checking
Regarding place for installation
Consult with your dealer for details on installation and transferring the
installation.
Caution:
Never install the Fresh Master where there is a risk of leakage of
flammable gas.
If gas leaks and accumulates around the unit, fire can result.
Never install the Fresh Master at the following place:
•where there is much machine oil
•near ocean and beach areas where there is much salt
•where humidity is high
•where there are hot springs nearby
•where there is much sulfureted gas
•where there is a high-frequency processing machinery (a high-fre-
quency welder, etc.)
•where acid solution is frequently used
•where special sprays are frequently used
•Install the Fresh Master horizontally. Otherwise, water leakage can
result.
•Take sufficient measures against noise when installing the Fresh
Master at hospitals or communication-related businesses.
If the Fresh Master is used in any of the above-mentioned environ-
ments, frequent operational failure can be expected. It is advisable
to avoid these types of installation sites.
For further details, consult with your dealer.
Regarding electrical work
Caution:
• The electrical work must be undertaken by a person who is
qualified as an electric engineer according to the [technical
standard respecting electrical installation], [internal wiring
rules], and the installation instruction manual with the abso-
lute use of exclusive circuits. The use of other products with
the power source can result in burnt-out beakers and fuses.
• Never connect the grounding wire to a gas pipe, water pipe,
arrester, or telephone grounding wire. For details, consult with
your dealer.
• In some types of installation sites, the installation of an earth
leakage breaker is mandatory. For details, consult with your
dealer.
Regarding transfer of installation
•When removing and reinstalling the Fresh Master when you en-
large your home, remodel, or move, consult with your dealer in
advance to ascertain the cost of the professional engineering work
required for transferring the installation.
Caution:
When moving or reinstalling the Fresh Master, consult with your
dealer. Defective installation can result in electric shock, fire, etc.
Regarding noise
•In installing work, choose a place that can fully bear the weight of
the Fresh Master and outdoor unit, and where noise and vibration
can be reduced.
•Choose a place where cool or warm air and noise from the outdoor
unit’s air outlet do not inconvenience the neighbors.
•If any alien object is placed near the outdoor unit’s air outlet, de-
creased performance and increased noise can result. Avoid plac-
ing any obstacles adjacent to the air outlet.
•If the Fresh Master or outdoor unit produces any abnormal sound,
consult with your dealer.
Maintenance and inspection
•If the Fresh Master and outdoor unit is used throughout several
seasons, the insides can get dirty, reducing the performance.
Depending upon the conditions of usage, foul odours can be gen-
erated and drainage can deteriorate due to dust and dirt, etc.
Time to change the humidifying element(GUF-50•100RDH3only)
Because impurities and contamination in tap water accumulate on the
humidifying element, the humidifying power of the humidifying element
decreases gradually.
•If the humidifying power decreases in the course of use, please con-
sider changing the humidifying element (chargeable to the customer).
•Although the time to change the humidifying element varies de-
pending on the conditions such as the operating time and water
quality, it should generally be changed at every five years.

Related Links Model Number: GUF-50RD3
GUF-50RD3 Service Manual U167 0 1
GUF-50-100RD3 Installation Manual
GUF-50-100RD3 Instruction Book
GUF-50-100RD3 Parts Catalogue
GUF-50-100RD3 Declaration of Conformity