Fujitsu UTZ-BD035B, UTZ-BD025B, UTZ-BD050B, UTZ-BD100B, UTZ-BD080B Technical Manual

DTO_ERV002E_01

2013.04.26

DESIGN & TECHNICAL MANUAL

UTZ-BD025B

UTZ-BD035B

UTZ-BD050B

UTZ-BD080B

UTZ-BD100B

ENERGY RECOVERY VENTILATORS

CONTENTS

1. SPECIFICATIONS

1-1. SPECIFICATIONS ........................................................................

01-01

2. DIMENTIONS

2-1. UTZ-BD025B ................................................................................

01-03

2-2. UTZ-BD035B ................................................................................

01-05

2-3. UTZ-BD050B ................................................................................

01-07

2-4. UTZ-BD080B ................................................................................

01-09

2-5. UTZ-BD100B .................................................................................

01-11

3. WIRING DIAGRAMS

3-1. UTZ-BD025B ................................................................................

01-13

3-2. UTZ-BD035B, UTZ-BD050B ........................................................

01-13

3-3. UTZ-BD080B, UTZ-BD100B ........................................................

01-14

3-4. INTERLOCKED CONNECTION TO AIR CONDITIONER ............

01-15

4. DESIGN SECTION

4-1. ABOUT HEAT EXCHANGE UNIT ................................................

01-17

4-1-1. BASIC ENGIN .........................................................................................

01-17

4-1-2. INTERNAL STRUCTURE .......................................................................

01-18

4-1-3. HEAT EXCHANGE VENTILATION AND NORMAL VENTILATION .......

01-19

4-2. NEEDS FOR VENTILATION .........................................................

01-20

4-2-1. OBJECTIVES AND EFFECTS OF VENTILATION .................................

01-20

4-3. METHODS OF VENTILATION ......................................................

01-21

4-4. DESIGN PRECAUTIONS .............................................................

01-22

4-4-1. CAUTION ON SAFETY ...........................................................................

01-22

4-4-2. INSPECTION OPENING AND INSTALLATION MODELS .....................

01-23

4-4-3. USE ENVIRONMENTS ...........................................................................

01-24

4-4-4. HEAT EXCHANGE EFFICIENCY ...........................................................

01-25

4-4-5. DUST COLLECTION EFFICIENCY ........................................................

01-27

4-4-6. NOISE .....................................................................................................

01-28

4-4-7. NOISE CONTROL ...................................................................................

01-29

4-5. VENTILATION DESIGN ................................................................

01-31

4-5-1. QUANTITY, DYNAMIC PRESSURE / STATIC PRESSURE ....................

01-31

4-5-2.

HOW TO CALCULATE REQUIRED VENTILATION VOLUME .................

01-32

4-6. DUCT DESIGN ..............................................................................

01-33

4-6-1. CALCULATION OF PRESSURE LOSSES DUE TO VENTILATION

THROUGH DUCT ....................................................................................

01-33

- (01-01) -

1. SPECIFICATIONS

1-1. SPECIFICATIONS

Model No.

Item

UTZ-BD025B

Power Source 220–240V~ 50Hz

Ventilation Mode Heat Exchange Ventilation Normal Ventilation

Notch (Extra high) High Low (Extra high) High Low

Input (W) 112-128 108-123 87-96 112-128 108-123 87-96

Air Volume (m3/h) 250 250 190 250 250 190

External Static Pressure (Pa) 105 95 45 105 95 45

Sound Pressure Level (dB) 30.0-31.5 29.5-30.5 23.5-26.5 30.0-31.5 29.5-30.5 23.5-26.5

Temperature Exchange

Efciency (%)

75 75 77 — — —

Dimensions (mm)
(H x W x D)

Net 270 x 882 x 599

Gross 349 x 1132 x 795

Weight (kg)

Net 29

Gross 35

Outlet Duct Diameter (mm) 150

Operation Range (°C) -10 to 40
Maximum Humidity (%) 85

Model No.

Item

UTZ-BD035B

Power Source 220–240V~ 50Hz

Ventilation Mode Heat Exchange Ventilation Normal Ventilation

Notch (Extra high) High Low (Extra high) High Low

Input (W) 182-190 178-185 168-175 182-190 178-185 168-175

Air Volume (m3/h) 350 350 240 350 350 240

External Static Pressure (Pa) 140 60 45 140 60 45

Sound Pressure Level (dB) 32.5-33.0 30.5-31.0 22.5-25.5 32.5-33.0 30.5-31.0 22.5-25.5

Temperature Exchange

Efciency (%)

75 75 78 — — —

Dimensions (mm)
(H x W x D)

Net 317 x 1050 x 804

Gross 396 x 1250 x 1000

Weight (kg)

Net 49

Gross 57

Outlet Duct Diameter (mm) 150

Operation Range (°C) -10 to 40
Maximum Humidity (%) 85

Model No.

Item

UTZ-BD050B

Power Source 220–240V~ 50Hz

Ventilation Mode Heat Exchange Ventilation Normal Ventilation

Notch (Extra high) High Low (Extra high) High Low

Input (W) 263-289 204-225 165-185 263-289 204-225 165-185

Air Volume (m3/h) 500 500 440 500 500 440

External Static Pressure (Pa) 120 60 35 120 60 35

Sound Pressure Level (dB) 36.5-37.5 34.5-35.5 31.0-32.5 36.5-37.5 34.5-35.5 31.0-32.5

Temperature Exchange

Efciency (%)

75 75 76 — — —

Dimensions (mm)
(H x W x D)

Net 317 x 1090 x 904

Gross 396 x 1290 x 1100

Weight (kg)

Net 57

Gross 66

Outlet Duct Diameter (mm) 200

Operation Range (°C) -10 to 40
Maximum Humidity (%) 85

- (01-02) -

Model No.

Item

UTZ-BD080B

Power Source 220–240V~ 50Hz

Ventilation Mode Heat Exchange Ventilation Normal Ventilation

Notch (Extra high) High Low (Extra high) High Low

Input (W) 387-418 360-378 293-295 387-418 360-378 293-295

Air Volume (m3/h) 800 800 630 800 800 630

External Static Pressure (Pa) 140 110 55 140 110 55

Sound Pressure Level (dB) 37.0-37.5 36.5-37.0 33.5-34.5 37.0-37.5 36.5-37.0 33.5-34.5

Temperature Exchange

Efciency (%)

75 75 76 — — —

Dimensions (mm)
(H x W x D)

Net 388 x 1322 x 884

Gross 467 x 1552 x 1170

Weight (kg)

Net 71

Gross 82

Outlet Duct Diameter (mm) 250

Operation Range (°C) -10 to 40
Maximum Humidity (%) 85

Model No.

Item

UTZ-BD100B

Power Source 220–240V~ 50Hz

Ventilation Mode Heat Exchange Ventilation Normal Ventilation

Notch (Extra high) High Low (Extra high) High Low

Input (W) 437-464 416-432 301-311 437-464 416-432 301-311

Air Volume (m3/h) 1000 1000 700 1000 1000 700

External Static Pressure (Pa) 105 80 75 105 80 75

Sound Pressure Level (dB) 37.5-38.5 37.0-37.5 33.5-34.5 39.5-40.5 39.0-39.5 35.5-36.5

Temperature Exchange

Efciency (%)

75 75 76 — — —

Dimensions (mm)
(H x W x D)

Net 388 x 1322 x 1134

Gross 467 x 1552 x 1420

Weight (kg)

Net 83

Gross 98

Outlet Duct Diameter (mm) 250

Operation Range (°C) -10 to 40
Maximum Humidity (%) 85

(Note) This noise of the product is the value which was measured at the acoustic room.

Actually, in the established condition, that undergo inuence by the echoing of the room and so that become bigger

than the display numerical value.

- (01-03) -

2. DIMENTIONS

2-1. UTZ-BD025B

NO.

Parts Name

Qty.

Material Remarks

1

Frame

1

Galvanized sheets

2

Adapter

4

ABS

3

Electrical Equipment Box

1

4

Inspection Cover

1

Galvanized sheets

5

Fan

2

ABS

6

Motor

2

7

Heat Exchange Element1Special paper + Resin

8

Filter

2

Nylon-Polyester Fiber Collection Efciency AFI 82%

9

Damper

1

10

Damper Motor

1

11

Ceiling Suspension Fixture4Galvanized sheets





BE CAREFUL OF DEWING AND
FROSTING

As shown in the Figure, suppose a high temp absorbing air condition
A and a low temp absorbing air condition B are plotted on the air line
gure, then a high temp air A is heat-exchanged by the unit and goes
out of the saturation curve as shown by Point C.
In this case, the unit will be dewed or frosted.
To aboid this, you are required to heat a low temp air B up to B’ so as
to get C’ below the saturation curve, before using the unit.

saturationcurve

Dry-bulb temperature(˚C)

Absolite humidity (kg/kg’)

C’

C

B

B’

A



REFERENCE SKETCH

Pipe Hood

Outside Intake Duct

Ceilling Suspension Bolts

Supply Air Duct

EA

(Exhaust

Air)

OA
(Outside intake Air)

RA

(Room Air)

SA

(Supply Air)

Inside Supply Opening

(Supply/Exhaust Air Grill)

Room Intake Opening

(Supply/Exhaust Air Grill)

Room Intake Duct

Heat Insulation Material

Exhaust Air Duct

The two outside ducts(the Outside Intake Duct and the

Exhaust Duct)must be insulated to prevent condensation.
(Material; Glass wool, Thickness; 25)



Duct size (Nominal Diameter): ø150



The above dimensions do not include the thickness of

the insulasion material on the unit body.

② ⑤ ⑥ ⑩ ⑨

①

⑦

⑪

599600

142 315 142

EA

OA

(Exhaust Air)

(Outside Air)

810

Maintenance Space

Inspection Opening □450

(For the inspection of the lters, heat exchange elements, fans, motors, and damper)

4-13×30 Oval hole · Suspension Fittings

1965519

RA

SA

(Room Air)

(Supply Air)

An inspection opening is necessary to

clean the heat exchange element and

lter once or twice a year.

270

247

159

135

12

80

④

⑧

③

882

414

95

95

Wiring Diagram

Earth Terminal

Ø219

Ø164

Ø144

67

157

- (01-04) -



SPECIFICATIONS

Model

No.

Power

Source

Notch

Frequency

Heat Exchange Ventilation Normal Ventilation

Product

Weight

Input Current

Air

Volume

External

Static

Pressure

Temperature

Exchange

Efciency

Enthalpy

Exchange

Efciency (%)

Noise Input Current

Air

Volume

External

Static

Pressure

Noise

(Hz) (W) (A) (m3/h) (Pa) (%) Cooling Heating (dB) (W) (A) (m3/h) (Pa) (dB) (kg)

UTZ-

BD025B

220-240V

a.c.

Extra High

50 112-128 0.51-0.53 250 105 75 63 70 30.0-31.5 112-128 0.51-0.53 250 105 30.0-31.5

29

High

50 108-123 0.49-0.51 250 95 75 63 70 29.5-30.5 108-123 0.49-0.51 250 95 29.5-30.5

Low

50 87-96 0.40-0.41 190 45 77 65 72 23.5-26.5 87-96 0.40-0.41 190 45 23.5-26.5



This noise of the product is the value which was measured at the acoustic room. Actually, in the established condition, that undergo inuence

by the echoing of the room and so that become bigger than the display numerical value .



PERFORMANCE

Use conditions

Outdoor air conditions

Temperature range -10˚C ~ 40˚C
Relative humidity 85% or less

Indoor air conditions

Temperature range -10˚C ~ 40˚C
Relative humidity 85% or less

Installation requirements

Same as the indoor air conditions

*

Indoor air here means air in air-conditioned
living rooms.
Its use in refrigerators or other place s

where temperature can uctuate greatly is
prohibited even if a temperature range is
acceptable.

Example

Indoor air conditions

During cooling period

Temperature 27˚C
Relative humidity 50%

During heating period

Temperature 20˚C
Relative humidity 40%

• The Input, the current and the exchange
efficiency are values at the time of the

mentioned air volume.

• The noise level shall be measured 1.5m
below the center of the unit.

• Th e temp erat ure exch ange effic ienc y

averages that of when cooling and when
heating.



MOTOR
SPECIFICATIONS

Type

4 Poles open type

induction motor

Rating Cont.

Insulation Class class E

Temperature Rise under 75 K

Sorrounding Temperature

-10˚C ~ 40˚C

Insulation Resistance

over 1MΩ (by DC500V)

Withstand Voltage AC 1,500V for 1min

300

0 50 100 150 200 250 300 350

50

100

150

200

250

0 20 40 60 80 100 120 140 160 180 200 220

Air Volume (m

3

/h)

Air Volume (ft

3

/min)

External Static Pressure (Pa)

80

50

60

70

Exchange Efciency (%)

Duct resistance Curve

P-Q Curve

220 - 240V ~ 50HzEfciency Curve

T

e

m

pe

ra

t

u

r

e

E

nt

h

al

p

y

(i

n

h

e

a

t

i

n

g

)

E

nt

h

al

p

y

(i

n

c

o

o

li

n

g

)

Extra High

Equivalent pipe length

High

Low



When friction coefcient of pipe (duct) :

=0.02

100m

80

60

20

40

- (01-05) -

2-2. UTZ-BD035B

NO.

Parts Name

Qty.

Material Remarks

1

Frame

1

Galvanized sheets

2

Adapter

4

ABS

3

Electrical Equipment Box

1

4

Inspection Cover

1

Galvanized sheets

5

Fan

2

ABS

6

Motor

2

7

Heat Exchange Element2Special paper + Resin

8

Filter

2

Nylon-Polyester Fiber Collection Efciency AFI 82%

9

Damper

1

10

Damper Motor

1

11

Ceiling Suspension Fixture4Galvanized sheets





BE CAREFUL OF DEWING AND
FROSTING

As shown in the Figure, suppose a high temp absorbing air condition
A and a low temp absorbing air condition B are plotted on the air line
gure, then a high temp air A is heat-exchanged by the unit and goes
out of the saturation curve as shown by Point C.
In this case, the unit will be dewed or frosted.
To aboid this, you are required to heat a low temp air B up to B’ so as
to get C’ below the saturation curve, before using the unit.

saturationcurve

Dry-bulb temperature(˚C)

Absolite humidity (kg/kg’)

C’

C

B

B’

A



REFERENCE SKETCH

Pipe Hood

Outside Intake Duct

Ceilling Suspension Bolts

Supply Air Duct

EA

(Exhaust

Air)

OA
(Outside intake Air)

RA

(Room Air)

SA

(Supply Air)

Inside Supply Opening

(Supply/Exhaust Air Grill)

Room Intake Opening

(Supply/Exhaust Air Grill)

Room Intake Duct

Heat Insulation Material

Exhaust Air Duct

The two outside ducts(the Outside Intake Duct and the

Exhaust Duct)must be insulated to prevent condensation.
(Material;Glass wool, Thickness;25)



Duct size (Nominal Diameter): ø150



The above dimensions do not include the thickness of

the insulasion material on the unit body.

978

② ⑤ ⑥

⑩

⑨

①

⑦

⑪

804600

112 580 112

EA

OA

(Exhaust Air)

(Outside Air)

Maintenance Space

Inspection Opening □450

(For the inspection of the lters, heat exchange elements, fans, motors, and damper)

4-13×30 Oval hole · Suspension Fittings

1986019

RA

SA

(Room Air)

(Supply Air)

An inspection opening is necessary to

clean the heat exchange element and

lter once or twice a year.

317

247

182

159

35

80

④

⑧

③

1050

470

70

70

Wiring Diagram

Earth Terminal

Ø162

Ø144

122

157

- (01-06) -



SPECIFICATIONS

Model

No.

Power

Source

Notch

Frequency

Heat Exchange Ventilation Normal Ventilation

Product

Weight

Input Current

Air

Volume

External

Static

Pressure

Temperature

Exchange

Efciency

Enthalpy

Exchange

Efciency (%)

Noise Input Current

Air

Volume

External

Static

Pressure

Noise

(Hz) (W) (A) (m3/h) (Pa) (%) Cooling Heating (dB) (W) (A) (m3/h) (Pa) (dB) (kg)

UTZ-

BD035B

220-240V

a.c.

Extra High

50 182-190 0.63-0.65 350 140 75 66 69 32.5-33.0 182-190 0.63-0.65 350 140 32.5-33.0

49

High

50 178-185 0.59-0.60 350 60 75 66 69 30.5-31.0 178-185 0.59-0.60 350 60 30.5-31.0

Low

50 168-175 0.56-0.57 240 45 78 71 73 22.5-25.5 168-175 0.56-0.57 240 45 22.5-25.5



This noise of the product is the value which was measured at the acoustic room. Actually, in the established condition, that undergo inuence

by the echoing of the room and so that become bigger than the display numerical value .



PERFORMANCE

Use conditions

Outdoor air conditions

Temperature range -10˚C ~ 40˚C
Relative humidity 85% or less

Indoor air conditions

Temperature range -10˚C ~ 40˚C
Relative humidity 85% or less

Installation requirements

Same as the indoor air conditions

*

Indoor air here means air in air-conditioned
living rooms.
Its use in refrigerators or other place s

where temperature can uctuate greatly is
prohibited even if a temperature range is
acceptable.

Example

Indoor air conditions

During cooling period

Temperature 27˚C
Relative humidity 50%

During heating period

Temperature 20˚C
Relative humidity 40%

• The Input, the current and the exchange
efficiency are values at the time of the

mentioned air volume.

• The noise level shall be measured 1.5m
below the center of the unit.

• Th e temp erat ure exch ange effic ienc y

averages that of when cooling and when
heating.



MOTOR
SPECIFICATIONS

Type

4 Poles open type

induction motor

Rating Cont.

Insulation Class class E

Temperature Rise under 75 K

Sorrounding Temperature

-10˚C ~ 40˚C

Insulation Resistance

over 1MΩ (by DC500V)

Withstand Voltage AC 1,500V for 1min

350

0 100 200 300 400 500 600

50

100

150

200

300

0 50 100 150 200 250 300 350

Air Volume (m

3

/h)

Air Volume (ft

3

/min)

External Static Pressure (Pa)

80

50

60

70

Exchange Efciency (%)

Duct resistance Curve

P-Q Curve 220 - 240V ~ 50HzEfciency Curve

T

e

m

p

e

r

a

t

u

r

e

E

n

t

h

a

l

p

y

(

i

n

h

e

a

t

i

n

g

)

E

n

t

h

a

l

p

y

(

i

n

c

o

o

l

i

n

g

)

Extra High

Equivalent pipe length

High

Low



When friction coefcient of pipe (duct) :

=0.02

60m

40

20

250

10

- (01-07) -

2-3. UTZ-BD050B

NO.

Parts Name

Qty.

Material Remarks

1

Frame

1

Galvanized sheets

2

Adapter

4

Galvanized sheets

3

Electrical Equipment Box

1

4

Inspection Cover

1

Galvanized sheets

5

Fan

2

ABS

6

Motor

2

7

Heat Exchange Element2Special paper + Resin

8

Filter

2

Nylon-Polyester Fiber Collection Efciency AFI 82%

9

Damper

1

10

Damper Motor

1

11

Ceiling Suspension Fixture4Galvanized sheets





BE CAREFUL OF DEWING AND
FROSTING

As shown in the Figure, suppose a high temp absorbing air condition
A and a low temp absorbing air condition B are plotted on the air line
gure, then a high temp air A is heat-exchanged by the unit and goes
out of the saturation curve as shown by Point C.
In this case, the unit will be dewed or frosted.
To aboid this, you are required to heat a low temp air B up to B’ so as
to get C’ below the saturation curve, before using the unit.

saturationcurve

Dry-bulb temperature(˚C)

Absolite humidity (kg/kg’)

C’

C

B

B’

A



REFERENCE SKETCH

Pipe Hood

Outside Intake Duct

Ceilling Suspension Bolts

Supply Air Duct

EA

(Exhaust

Air)

OA
(Outside intake Air)

RA

(Room Air)

SA

(Supply Air)

Inside Supply Opening

(Supply/Exhaust Air Grill)

Room Intake Opening

(Supply/Exhaust Air Grill)

Room Intake Duct

Heat Insulation Material

Exhaust Air Duct

The two outside ducts(the Outside Intake Duct and the

Exhaust Duct)must be insulated to prevent condensation.
(Material;Glass wool, Thickness;25)



Duct size (Nominal Diameter): ø200



The above dimensions do not include the thickness of

the insulasion material on the unit body.

②

⑤

⑥

⑩

⑨

①

⑦

⑪

904600

132 640 132

EA

OA

(Exhaust Air)

(Outside Air)

1018

Maintenance Space

Inspection Opening □450
(For the inspection of the lters, heat exchange elements, fans, motors, and damper)

4-13×30 Oval hole · Suspension Fittings

1996019

RA

SA

(Room Air)

(Supply Air)

An inspection opening is necessary to

clean the heat exchange element and

lter once or twice a year.

317

159

182

247

35

80

④

⑧

③

1090

470

127

70

Wiring Diagram

Earth Terminal

Ø210

Ø194

157

70

- (01-08) -



SPECIFICATIONS

Model

No.

Power

Source

Notch

Frequency

Heat Exchange Ventilation Normal Ventilation

Product

Weight

Input Current

Air

Volume

External

Static

Pressure

Temperature

Exchange

Efciency

Enthalpy

Exchange

Efciency (%)

Noise Input Current

Air

Volume

External

Static

Pressure

Noise

(Hz) (W) (A) (m3/h) (Pa) (%) Cooling Heating (dB) (W) (A) (m3/h) (Pa) (dB) (kg)

UTZ-

BD050B

220-240V

a.c.

Extra High

50 263-289 1.20-1.21 500 120 75 62 67 36.5-37.5 263-289 1.20-1.21 500 120 36.5-37.5

57

High

50 204-225 0.93-0.94 500 60 75 62 67 34.5-35.5 204-225 0.93-0.94 500 60 34.5-35.5

Low

50 165-185 0.75-0.77 440

35

76 64 69 31.0-32.5 165-185 0.75-0.77 440

35

31.0-32.5



This noise of the product is the value which was measured at the acoustic room. Actually, in the established condition, that undergo inuence

by the echoing of the room and so that become bigger than the display numerical value .



PERFORMANCE

Use conditions

Outdoor air conditions

Temperature range -10˚C ~ 40˚C
Relative humidity 85% or less

Indoor air conditions

Temperature range -10˚C ~ 40˚C
Relative humidity 85% or less

Installation requirements

Same as the indoor air conditions

*

Indoor air here means air in air-conditioned
living rooms.
Its use in refrigerators or other place s

where temperature can uctuate greatly is
prohibited even if a temperature range is
acceptable.

Example

Indoor air conditions

During cooling period

Temperature 27˚C
Relative humidity 50%

During heating period

Temperature 20˚C
Relative humidity 40%

• The Input, the current and the exchange
efficiency are values at the time of the

mentioned air volume.

• The noise level shall be measured 1.5m
below the center of the unit.

• Th e temp erat ure exch ange effic ienc y

averages that of when cooling and when
heating.



MOTOR
SPECIFICATIONS

Type

4 Poles open type

induction motor

Rating Cont.

Insulation Class class E

Temperature Rise under 75 K

Sorrounding Temperature

-10˚C ~ 40˚C

Insulation Resistance

over 1MΩ (by DC500V)

Withstand Voltage AC 1,500V for 1min

400

0 100 200 300 400 500 600 700 800

50

100

150

200

300

0 50 100 150 200 250 300 350 400 450

Air Volume (m

3

/h)

Air Volume (ft

3

/min)

External Static Pressure (Pa)

80

50

60

70

Exchange Efciency (%)

Duct resistance Curve

P-Q Curve

220 - 240V ~ 50HzEfciency Curve

T

e

m

p

e

r

a

t

u

r

e

E

n

t

h

a

l

p

y

(

i

n

h

e

a

t

i

n

g

)

E

n

t

h

a

l

p

y

(

i

n

c

o

o

l

i

n

g

)

Extra High

Equivalent pipe length

High

Low



When friction coefcient of pipe (duct) :

=0.02

100m

60

40

250

20

350

80

- (01-09) -

2-4. UTZ-BD080B

NO.

Parts Name

Qty.

Material Remarks

1

Frame

1

Galvanized sheets

2

Adapter

4

Galvanized sheets

3

Electrical Equipment Box

1

4

Inspection Cover

1

Galvanized sheets

5

Fan

2

ABS

6

Motor

2

7

Heat Exchange Element3Special paper + Resin

8

Filter

2

Nylon-Polyester Fiber Collection Efciency AFI 82%

9

Damper

1

10

Damper Motor

1

11

Ceiling Suspension Fixture4Galvanized sheets





BE CAREFUL OF DEWING AND
FROSTING

As shown in the Figure, suppose a high temp absorbing air condition
A and a low temp absorbing air condition B are plotted on the air line
gure, then a high temp air A is heat-exchanged by the unit and goes
out of the saturation curve as shown by Point C.
In this case, the unit will be dewed or frosted.
To aboid this, you are required to heat a low temp air B up to B’ so as
to get C’ below the saturation curve, before using the unit.

saturationcurve

Dry-bulb temperature (˚C)

Absolite humidity (kg/kg’)

C’

C

B

B’

A



REFERENCE SKETCH

Pipe Hood

Outside Intake Duct

Ceilling Suspension Bolts

Supply Air Duct

EA

(Exhaust

Air)

OA
(Outside intake Air)

RA

(Room Air)

SA

(Supply Air)

Inside Supply Opening

(Supply/Exhaust Air Grill)

Room Intake Opening

(Supply/Exhaust Air Grill)

Room Intake Duct

Heat Insulation Material

Exhaust Air Duct

The two outside ducts(the Outside Intake Duct and the

Exhaust Duct)must be insulated to prevent condensation.
(Material;Glass wool, Thickness;25)



Duct size (Nominal Diameter): ø250



The above dimensions do not include the thickness of

the insulasion material on the unit body.

②

⑤

⑥

⑩

⑨

①

⑦

⑪

884600

228 428 228

EA

OA

(Exhaust Air)

(Outside Air)

1250

Maintenance Space

Inspection Opening □450
(For the inspection of the lters, heat exchange elements, fans, motors, and damper)

4-13×30 Oval hole · Suspension Fittings

1994019

RA

SA

(Room Air)

(Supply Air)

⑧

An inspection opening is necessary to

clean the heat exchange element and

lter once or twice a year.

388

194

218

247101

80

④

⑧

③

1322

612

85

85

Wiring Diagram

Earth Terminal

Ø258

Ø242

184157

- (01-10) -



SPECIFICATIONS

Model

No.

Power

Source

Notch

Frequency

Heat Exchange Ventilation Normal Ventilation

Product

Weight

Input Current

Air

Volume

External

Static

Pressure

Temperature

Exchange

Efciency

Enthalpy

Exchange

Efciency (%)

Noise Input Current

Air

Volume

External

Static

Pressure

Noise

(Hz) (W) (A) (m3/h) (Pa) (%) Cooling Heating (dB) (W) (A) (m3/h) (Pa) (dB) (kg)

UTZ-

BD080B

220-240V

a.c.

Extra High

50 387-418 1.74-1.76 800 140 75 65 71 37.0-37.5 387-418 1.74-1.76 800 140 37.0-37.5

71

High

50 360-378 1.58-1.64 800 110 75 65 71 36.5-37.0 360-378 1.58-1.64 800 110 36.5-37.0

Low

50 293-295 1.23-1.33 630 55 76 68 74 33.5-34.5 293-295 1.23-1.33 630 55 33.5-34.5



This noise of the product is the value which was measured at the acoustic room .Actually, in the established condition, that undergo inuence

by the echoing of the room and so that become bigger than the display numerical value .



PERFORMANCE

400

0 100 200 300 400 500 600 700 800 900 1000 1100 1200

50

100

150

200

300

0 100 200 300 400 500 600 700

Air Volume (m

3

/h)

Air Volume (ft

3

/min)

External Static Pressure (Pa)

80

50

60

70

Exchange Efciency (%)

Duct resistance Curve

P-Q Curve

220 - 240V ~ 50HzEfciency Curve

T

e

m

p

e

r

a

t

u

r

e

E

n

t

h

a

l

p

y

(

i

n

h

e

a

t

i

n

g

)

E

n

t

h

a

l

p

y

(

i

n

c

o

o

l

i

n

g

)

Extra High

Equivalent pipe length

High

Low



When friction coefcient

of pipe (duct) :

=0.02

100m

60

40

250

20

350

80

90450

500

Use conditions

Outdoor air conditions

Temperature range -10˚C ~ 40˚C
Relative humidity 85% or less

Indoor air conditions

Temperature range -10˚C ~ 40˚C
Relative humidity 85% or less

Installation requirements

Same as the indoor air conditions

*

Indoor air here means air in air-conditioned
living rooms.
Its use in refrigerators or other place s

where temperature can uctuate greatly is
prohibited even if a temperature range is
acceptable.

Example

Indoor air conditions

During cooling period

Temperature 27˚C
Relative humidity 50%

During heating period

Temperature 20˚C
Relative humidity 40%

• The Input, the current and the exchange
efficiency are values at the time of the

mentioned air volume.

• The noise level shall be measured 1.5m
below the center of the unit.

• Th e temp erat ure exch ange effic ienc y

averages that of when cooling and when
heating.



MOTOR
SPECIFICATIONS

Type

4 Poles open type

induction motor

Rating Cont.

Insulation Class class E

Temperature Rise under 75 K

Sorrounding Temperature

-10˚C ~ 40˚C

Insulation Resistance

over 1MΩ (by DC500V)

Withstand Voltage AC 1,500V for 1min

- (01-11) -

2-5. UTZ-BD100B

NO.

Parts Name

Qty.

Material Remarks

1

Frame

1

Galvanized sheets

2

Adapter

4

Galvanized sheets

3

Electrical Equipment Box

1

4

Inspection Cover

1

Galvanized sheets

5

Fan

2

ABS

6

Motor

2

7

Heat Exchange Element4Special paper + Resin

8

Filter

2

Nylon-Polyester Fiber Collection Efciency AFI 82%

9

Damper

1

10

Damper Motor

1

11

Ceiling Suspension Fixture4Galvanized sheets





BE CAREFUL OF DEWING AND
FROSTING

As shown in the Figure, suppose a high temp absorbing air condition
A and a low temp absorbing air condition B are plotted on the air line
gure, then a high temp air A is heat-exchanged by the unit and goes
out of the saturation curve as shown by Point C.
In this case, the unit will be dewed or frosted.
To aboid this, you are required to heat a low temp air B up to B’ so as
to get C’ below the saturation curve, before using the unit.

saturationcurve

Dry-bulb temperature (˚C)

Absolite humidity (kg/kg’)

C’

C

B

B’

A



REFERENCE SKETCH

Pipe Hood

Outside Intake Duct

Ceilling Suspension Bolts

Supply Air Duct

EA

(Exhaust

Air)

OA
(Outside intake Air)

RA

(Room Air)

SA

(Supply Air)

Inside Supply Opening

(Supply/Exhaust Air Grill)

Room Intake Opening

(Supply/Exhaust Air Grill)

Room Intake Duct

Heat Insulation Material

Exhaust Air Duct

The two outside ducts(the Outside Intake Duct and the

Exhaust Duct)must be insulated to prevent condensation.
(Material;Glass wool, Thickness;25)



Duct size (Nominal Diameter): ø250



The above dimensions do not include the thickness of

the insulasion material on the unit body.

②

⑤

⑥

⑩

⑨

①

⑦

⑪

1134600

228 678 228

EA

OA

(Exhaust Air)

(Outside Air)

1250

Maintenance Space

Inspection Opening □450
(For the inspection of the lters, heat exchange elements, fans, motors, and damper)

4-13×30 Oval hole

· Suspension Fittings

19119019

RA

SA

(Room Air)

(Supply Air)

⑧

An inspection opening is necessary to

clean the heat exchange element and

lter once or twice a year.

388

194

218

247101

80

④

⑧

③

1322

612

85

85

Wiring Diagram

Earth Terminal

Ø258

Ø242

157 184

- (01-12) -



SPECIFICATIONS

Model

No.

Power

Source

Notch

Frequency

Heat Exchange Ventilation Normal Ventilation

Product

Weight

Input Current

Air

Volume

External

Static

Pressure

Temperature

Exchange

Efciency

Enthalpy

Exchange

Efciency (%)

Noise Input Current

Air

Volume

External

Static

Pressure

Noise

(Hz) (W) (A) (m3/h) (Pa) (%) Cooling Heating (dB) (W) (A) (m3/h) (Pa) (dB) (kg)

UTZ-

BD100B

220-240V

a.c.

Extra High

50 437-464 1.93-1.99 1000 105 75 65 71 37.5-38.5 437-464 1.93-1.99 1000 105 37.5-38.5

83

High

50 416-432 1.80-1.89 1000 80 75 65 71 37.0-37.5 416-432 1.80-1.89 1000 80 37.0-37.5

Low

50 301-311 1.29-1.37 700 75 79 70 76 33.5-34.5 301-311 1.29-1.37 700 75 33.5-34.5



This noise of the product is the value which was measured at the acoustic room. Actually, in the established condition, that undergo inuence

by the echoing of the room and so that become bigger than the display numerical value .



PERFORMANCE

400

0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300

50

100

150

200

300

0 100 200 300 400 500 600 700

Air Volume (m

3

/h)

Air Volume (ft

3

/min)

External Static Pressure (Pa)

80

50

60

70

Exchange Efciency (%)

Duct resistance Curve

P-Q Curve

220 - 240V ~ 50HzEfciency Curve

T

e

m

p

e

r

a

t

u

r

e

E

n

t

h

a

l

p

y

(

i

n

h

e

a

t

i

n

g

)

E

n

t

h

a

l

p

y

(

i

n

c

o

o

l

i

n

g

)

Extra High

Equivalent pipe length

High

Low



When friction coefcient

of pipe (duct) :

=0.02

100m

60

40

250

20

350

80

90

500

450

Use conditions

Outdoor air conditions

Temperature range -10˚C ~ 40˚C
Relative humidity 85% or less

Indoor air conditions

Temperature range -10˚C ~ 40˚C
Relative humidity 85% or less

Installation requirements

Same as the indoor air conditions

*

Indoor air here means air in air-conditioned
living rooms.
Its use in refrigerators or other place s

where temperature can uctuate greatly is
prohibited even if a temperature range is
acceptable.

Example

Indoor air conditions

During cooling period

Temperature 27˚C
Relative humidity 50%

During heating period

Temperature 20˚C
Relative humidity 40%

• The Input, the current and the exchange
efficiency are values at the time of the

mentioned air volume.

• The noise level shall be measured 1.5m
below the center of the unit.

• Th e temp erat ure exch ange effic ienc y

averages that of when cooling and when
heating.



MOTOR
SPECIFICATIONS

Type

4 Poles open type

induction motor

Rating Cont.

Insulation Class class E

Temperature Rise under 75 K

Sorrounding Temperature

-10˚C ~ 40˚C

Insulation Resistance

over 1MΩ (by DC500V)

Withstand Voltage AC 1,500V for 1min

- (01-13) -

3. WIRING DIAGRAMS

3-1. UTZ-BD025B

SW1

Switch

Low

Damper

High

Power Source

220-240V~single

phase 50Hz

Yellow Yellow

White

White

Black

Black

Blue

Connector

Connector

(Connector)

Connector

White

White(Extra high)

White

Black

Black

Black

Black

(Connector)

Capacitor

Capacitor

White

White

Yellow

Red

Blue(High)

Orange Orange

Red
Yellow
Blue

White(Extra high)

Blue(High)

Yellow

Red

Orange

Orange

Connector

Red

Yellow

Blue

Supply
Air Fan

Exhaust

Air Fan

Micro switch

Damper

Motor

Power Source
(Line)

Power Source
(Neutral)

High

Main unit

L

(Voltage)

N

(Ground)

SW1

SW2

Common

Low

Damper

Terminal

board

Grey

White

White

Blue

Black

Black

Red

Red

White

Black

Brown

Blue

Black

Red

Red

Black

White

Brown

Black

Black

Black

White

White

Yellow

Yellow

Relay 1

Relay 2

Relay 3

White

White
Yellow

Grey

Second main body

Function Select Switch
(3) Energy Recovery

Ventilation

(1) Normal Ventilation

To find out the function of
each switch, refer to Page 7
of the Owner’s manual.

Air Flow Switch
(3) High
(1) Low

Operation Switch

(3) (ON)
(1) (OFF)

UTZ-BD025B

3-2. UTZ-BD035B, UTZ-BD050B

SW1

Switch

Low

Damper

High

Power Source

220-240V~single

phase 50Hz

Power Source
(Line)

Power Source
(Neutral)

Second main body

High

Main unit

L

N

SW1

SW2

Common

Low

Damper

Terminal

board

Grey

White

White

Blue

Black

Black

Red

Red

White

Black

Brown

Blue

Black

Red

Red

Black

White

Brown

Black

Black

Black

White

White

Yellow

Yellow

Relay 1

Relay 2

Relay 3

White

White

Yellow

Grey

Black

Black

(Connector)

Capacitor

White

White

White(Extra high)

Blue(High)

Yellow

Red

Orange

Orange

Connector

Red

Yellow

Blue

Supply

Air Fan

(Connector)

Connector

White

White(Extra high)

White

Black

Black

Capacitor

Yellow

Red

Blue(High)

Orange Orange

Red
Yellow
Blue

Exhaust

Air Fan

Yellow Yellow

White

White

Black

Black

Blue

Connector

Connector

Micro switch

Damper

Motor

Function Select Switch
(3) Energy Recovery

Ventilation

(1) Normal Ventilation

Air Flow Switch
(3) High
(1) Low

Operation Switch

(3) (ON)
(1) (OFF)

UTZ-BD035B

Model No, Capacitor

3.5 µF 450VAC

6.0 µF 450VAC

UTZ-BD050B

- (01-14) -

3-3. UTZ-BD080B, UTZ-BD100B

UTZ-BD080B

Model No, Capacitor

10.0 µF 450VAC

10.0 µF 450VAC

UTZ-BD100B

SW1

Switch

Low

Damper

High

Blue

Black

Grey

Grey

Brown

Relay 4

Black

Red

Red

Black

White

Black

Black

White

White

Yellow

Yellow

Relay 1

Grey

Black

Relay 2

Relay 3

White

White
Yellow

Grey

Black

Black

(Connector)

Capacitor

White

White

White(Extra high)

Blue(High)

Yellow

Red

Orange

Orange

Connector

Red

Yellow

Blue

Supply

Air Fan

(Connector)

Connector

White

White(Extra high)

White

Black

Black

Capacitor

Yellow

Red

Blue(High)

Orange Orange

Red
Yellow
Blue

Exhaust

Air Fan

Yellow Yellow

White

White

Black

Black

Blue

Blue

Connector

Connector

Micro switch

Damper

Motor

Power Source
(Line)

Power Source
(Neutral)

High

Main unit

L

N

SW1

SW2

Common

Low

Damper

Terminal

board

Grey

White

White

Blue

Black

Black

Red

Red

White

Black

Brown

Blue

Second main body

Power Source

220-240V~single

phase 50Hz

Function Select Switch
(3) Energy Recovery

Ventilation

(1) Normal Ventilation

Air Flow Switch
(3) High
(1) Low

Operation Switch

(3) (ON)
(1) (OFF)

- (01-15) -

3-4. INTERLOCKED CONNECTION TO AIR CONDITIONER

● Operation is performed simultaneously with the air conditioner.

● Setting changes are made by energy recovery ventilator switch.
Relay

Air conditioner

Energy recovery ventilator

Air conditioner

remote controller

Energy recovery

ventilator switch





Connection method

● Perform electrical work in accordance with the laws and regulations of each country.

● Check whether or not there is an external output and the necessary connector terminals at the air conditioner using the air conditioner technical

manual beforehand. The external output (operation status output) of the indoor unit PC board is used.

● There is a type of external output from the air conditioner which requires an external power source and a type which does not require an

external power source. The type is different depending on the model.

● The allowable voltage/current of the external output circuit from the air conditioner varies depending on the model. Check it with the air

conditioner technical manual.

● Do not connect the energy recovery ventilator power source (AC220-240V) to the external output terminals from the air conditioner.

● Regarding the relay circuit, select the necessary capacity from the allowable current value of the external output terminals and the current value

of the energy recovery ventilator and connect.

(1) When energy recovery ventilator operation is unnecessary

For energy recovery ventilator, airflow switching and heat exchange ventilation / normal ventilation switching cannot be

performed.

The gure shown below indicates the operation with airow HIGH and heat exchange ventilation.

Provided at the site

Power source
AC220-240V
50Hz

Energy recovery ventilator

terminal

Indoor unit PC board

Relay circuit

L

N
SW1
SW2

COMMON

LOW

HIGH

DAMPER

N L

- (01-16) -

(2) When you want to operate using the energy recovery ventilator switch

Operation is performed simultaneously by air conditioner remote controller even when the energy recovery ventilator switch

is in the OFF state.

The energy recovery ventilator can be operated by energy recovery ventilator switch even when the air conditioner is in the

stopped state.

Do not make connections to multiple indoor units by duct direct connection system.

Dust may be dispersed depending on the operation condition of the air conditioner.

Energy recovery

ventilator

Dust

Room air

Room air

Stopped

External air

Operating

Power source
AC220-240V
50Hz

Energy recovery ventilator

terminal

Indoor unit PC board

Relay circuit

Provided at the site

Energy recovery

ventilator switch

L

N
SW1
SW2

COMMON

LOW

HIGH

DAMPER

N L

ON

OFF

HIGH

LOW

HEAT EXCHANGE

NORMAL

- (01-17) -

4. DESIGN SECTION

4-1. ABOUT HEAT EXCHANGE UNIT

4-1-1. BASIC ENGIN



BASIC PRINCIPLE AND
STRUCTURE OF THE HEAT
EXCHANGER



Basic principle of a heat exchanger

The basic principle of a heat exchanger is as indicated
below. As heat moves from a high-temperature area to a
low-temperature area together with humidity, the heated and
moist air moves the heat and humidity to colder and drier air
by passing through a heat-exchange element.

Warm and moist

ai

r

Heat-exchange element

Heat

Humidity

Cold and
dry air



Function of a heat exchanger

A heat exchanger effectively recovers cooled or heated room
temperatures and simultaneously ventilates air.

Winter



Mechanism of a heat exchange element

The heat exchange element can allow the exhaust air from
inside and the fresh air from outside to transmit temperature

and humidity without being mixed up.

Indoor exhaust

Outdoor inlet

Mechanism of total heat ex-

change

Heat

Indoor air

upply at 14

Humidity

s

Cold air at

0

Indoor air
supply

Outdoor
exhaust

Outdoor

exhaust at 6

Humidity

Heat exchange

element

0°C

6°C 14°C

20°C

Heat exchange

ratio at 70%

Warm air at
20

Heat



ADVANTAGES OF THE HEAT

EXCHANGE ELEMENT



The height of the heat exchange element

reduced by 20%

The upper and lower protrusions have been cut out (see the gure
below). The newly adopted counter-ow
heat exchange system has made the

entire unit much thinner from 287mm

to 230mm, and realized the same

performance as in the conventional

cross-ow heat exchange element.

Comparison of heat exchange elements

C tross-flow elemen

Counter-flow ele-

ment

While airflows are directly crossed in the cross-flow ele­ment, the counter-flow element allows airflow to be retained
for longer time (or longer distance). In this manner, the
thinner system can maintain the heat exchange perform­ance attained b

y

its thicker counterpart.



Total heat exchange efciency improved by

6%

The adoption of the counter-flow element has improved

the total heat exchange ratio by about 6%, significantly
contributing to energy saving.



Long-life heat exchange element

By adopting nonwoven fabric filter with excellent dust
collection efficiency and improving the air course shapes,
a long-life heat exchange system has been realized, which

does not require regular cleaning of the heat exchang e
element.

cross-flow element
After cleaning the
cross-flow element
The counter-flow element

Heat exchange element with

extended life

The cross-flow element
requires regular clean-ups.

A

irflow

resistance

Changes in airflow resistance
with the years of use

Cleaned

Used

Initial
level

1st

year

2nd

year

3rd

year

4th

year

5th

year

6th

year

7th

year

8th

year

9th

year

10th
year

Service year

The counter-flow element requires no regula
r

clean-up, as the resistance level hardly rise.

Before cleaning the

cross-flow element
After cleaning the
cross-flow element
The counter-flow element

Heat exchange element with

extended life

The cross-flow element
requires regular clean-ups.

A

irflow

resistance

Changes in airflow resistance
with the years of use

Cleaned

Used

Initial
level

1st

year

2nd
year

3rd

year

4th

year

5th

year

6th

year

7th

year

8th

year

9th

year

10th
year

Service year

The counter-flow element requires no regula

r

clean-up, as the resistance level hardly rise.

Long-life heat exchange element

Conventional element
(corrugated structure)

With the above features, airflow resistance affecting s ervice life har dly rises.

The end section is finished with the resin-formed
structure characterized by robustness
Bigger air-course per cell

The fin structure is seldom crushed or damaged.

Dirt and dust are seldom attached.

New-type element

Heat exchanger

plate (paper)

Hydraulic
diamete

r

Spacing plate

(paper)

Spacing rib (resin)

Heat exchanger

p

late(paper

)

Hydraulic

diamete

r

Before cleaning the

- (01-18) -

4-1-2. INTERNAL STRUCTURE



HEAT EXCHANGE UNIT

(CEILING-MOUNTED)



INTERNAL STRUCTURE

(HEAT EXCHANGE VENTILATION)

Bypass air course

Heat exchange

element

Filter (for RA)

Filter (for OA)



HEAT EXCHANGE UNIT

(CEILING-MOUNTED)



INTERNAL STRUCTURE

(NORMAL VENTILATION)

Bypass air course

Heat exchange

element

Filter (for RA)

Filter (for OA)

- (01-19) -

4-1-3. HEAT EXCHANGE VENTILATION AND NORMAL

VENTILATION



HEAT EXCHANGE VENTILATION

External air is heat-exchanged with indoor air, and supplied

indoors after the temperature is made closer to the room
temperature



NORMAL VENTILATION

External air is let in without heat-exchange with indoor air.



ATTENTION

 When the heating function is on during winter, do no use “normal ventilation.” The dew condensation will take place in the

unit, which may result in stains on the ceiling, etc.

Stale indoor air to be ex-

hausted (EA)

Fresh external air to be

su

pp

lied indoors(SA

)

Outdoor Indoor

Total heat

exchanger

Stale indoor air
(RA)

Fresh external

air (OA)

Fresh external air to be

supplied indoors (SA)

Stale indoor air to be

exhausted (EA)

Outdoor Indoor

Stale Indoor air
(RA)

Fresh external

air (OA)

Total heat

exchanger

- (01-20) -

4-2. NEEDS FOR VENTILATION

4-2-1. OBJECTIVES AND EFFECTS OF VENTILATION



EFFECTS OF VENTILATION

Ventilation is not simply designed to exhaust stale air. It also
has deodorizing, dust removal, dehumidification, and room
temperature adjustment functions, in addition to exchanging

air.

(1) Ventilation function
Ventilation supplies fresh air required t o sustain our

normal breathing and exhausts stale air; as well as
supplies oxygen required for combustion and prevents
imperfect combustion.

(2) Deodorizing function

A ventilation fan can quickly exhaust unpleasant odor

derived from various sources, and create comfortable

environment.

(3) Dust removal function

Dust oating in the air may accompany invisibly tiny various

harmful bacteria, etc. Dust and dirt should thus be exhausted
from room to create hygienic and comfortable environment.

(4) Dehumidication function
Humidity in a house is not limited to the bathroom. Moisture is

also emitted from human bodies and combustion appliances.
Particularly, in recent years, heating in a highly airtight
structure has caused dew condensation, resulting in mold
growth and even damaging oors and walls, etc. Eliminating
interior humidity through ventilation will create comfortable and
healthy conditions for both human bodies and buildings.

(5) Room temperature adjustment function

At summer nights, ventilation accompanied by refrigeration

air conditioning can eliminate warm room air by the
ventilator, and let in cool outdoor air. Circulation-type
ventilators can also maintain the room temperatures,
realizing highly efcient heating in winter.



EFFECTS OF STALE AIR ON

BUILDING



Stains on interior surfaces

Brand new white ceilings, walls, furniture, and decorative items
may turn yellowish in a year or two, due to tar contained in
cigarettes and oating dust.



Beware of humidity

Humidity emitted from one human body is said to amount to
about two liters a day. In highly airtight modern structures, in
addition to bathrooms, which are almost always humid, many
places can remain highly humid, such as living rooms, closets,
storerooms, and under-floor areas, etc. If left unattended,
mold and ticks will soon appear, and the wood may be more
likely to be rotted. In addition, heating will also accelerate dew
condensation, which may further damage portions behind walls
and oors, which are not readily visible.



NEEDS FOR AIR SUPPLY

Ventilation is to exchange indoor air with outdoor air. When

ventilation is performed by a ventilating fan (generally for the
exhausting function), if air inlet is limited (in a room or a building),
the capabilities of the ventilator may be greatly reduced, or the
indoor pressure may be lowered, causing drafts and noises, as
well as making it difcult to open or close doors.



Sizes and locations of inlets

(1) Sizes of air inlets

Required sizes of inlets may vary, depending on the sizes of apertures

and openings of the buildings. The effective opening area (cm2) should
be 0.7 times the ventilation airow (m3/h), with the internal and external

pressure difference set at 10Pa.

Effective opening area αA(cm2) = 0.7 x airow (m3/h)

As a reference, the following computation formulas are proposed

in the ventilation/air-conditioning engineering standards.
αA= 0.68V - S αA’ (in the case of Pmax = 10Pa)
αA= 0.39V - S αA’ (in the case of Pmax = 30Pa)
αA: Effective opening area (cm2) of dedicated inlets
V: Effective ventilation air volume (m3/h)

S: Gross oor area of a building (m2)

αA’: Air-tightness of a building (cm2/m2)

A ventilating fan has an exhaust capability specied in the catalog,

for which, however, the amount of air exhausted by the fan needs to

be supplied from the inlet.
In other words, if the air-inlet is small, sufficient air cannot be

supplied indoors, resulting in insufcient ventilation capacities. The

air-inlet should generally be larger than the installation area for the

ventilation fan. As the inlet area gets bigger, the air velocity there

will be reduced, making it less uncomfortable for people near it.

Ex-

haust

Ex-

haust

Smooth airflows

Slow air supply
velocity

High ai

r

supply

velocity,

causing

uncomfortable

feeling

Noisy

Insufficient

ventilation

capacity

Fig. 2-2Fig. 2-1

Ex-

haust

Smooth airflows

Slow air supply
velocity

Fig. 2-2Fig. 2-1

Air-inlet

Air-inlet

Ex-

haust

Ex-

haust

Smooth airflows

Slow air supply
velocity

High ai

r

supply

velocity,

causing

uncomfortable

feeling

Noisy

Insufficient

ventilation

capacity

Fig. 2-2Fig. 2-1

For a large room, air-inlets should
be dispersed and as far distanced
from the ventilating fans as possible,
so that air can be ventilated evenly.

Air-inlet Many portions of the

room remain unven­tilated.

A bad example

Fewer
portions
of the
room
remain
unventi­lated.

Air-inlet

A good example

Ventilating fans should also
be dispersed.

A good ex-

ample

Air

-inlet

Fig. 2-3

(2) Locations of exhausts (ventilation fans) and air-inlets

In the case of general ventilation, air-inlets should be located as

far detached from ventilating fans as possible. On the other hand,

in the case of local ventilation, the air-inlet should be as close

to the ventilating fans to minimize any effects to the surrounding

areas.

(3) In bathrooms,…

When ventilating fans are installed in bathrooms, etc., air-inlets should

always be installed (except for simultaneous exhaust/supply systems).

Otherwise, ventilating air volumes may be reduced, or the sealing

water may be disrupted in shallow traps, causing the sewage stench

to ow into the room.

(4)

In rooms where half-enclosed combustion apparatus are used

In a cold region, when a stove with a chimney is installed without

proper air-inlets, and ventilation fan is put into operation, the chimney

may function as an air-inlet and let the exhaust into the room, causing

a dangerous situation.

- (01-21) -

4-3. METHODS OF VENTILATION

Ventilation can be divided into natural ventilation based
on natural conditions and mechanical ventilation based on

mechanical power.



NATURAL VENTILATION

This ventilation is based on pressure

derived from external winds and
the outdoor and indoor temperature

differences. However, as natural

ventilation is weaker than mechanical

ventilation and may be greatly
affected by natural conditions,
signicant results cannot be expected



MECHANICAL VENTILATION



Methods of mechanical ventilation

As this method is based on enforced

ventilation with ventilating fans and air

blowers, etc., it is capable of generating
stable amounts of ventilation at
required timing, compared with natural

ventilation.

*

Highly contaminated rooms should

remain in negative pressure to prevent
contaminated air from leaking into
adjacent rooms and corridors (Class 1 or

Class 3 Ventilation). On the other hand,
for rooms that need to be kept clean,
positive pressure should be maintained

to prevent intrusion of contaminated air
(Class 2 Ventilation).



Total ventilation and local ventilation

 Total ventilation

This ventilation is designed for an
entire house and for exchanging
the entire air in the house (Fig.
3-5).

The total (general) ventilation can be categorized into the
following three types.

a) Individualized ventilation system
The amount of ventilation required for each room can be

satisfied by installing ventilation facilities at each room.
.………

b) Total ventilation system
The total amount of ventilation for the entire building

can be satisfied by utilizing local exhaust facilities and
installing natural air-supply inlet at each room. E.g., local
exhaust facilities + natural air-supply inlets, etc.

c) Central ventilation system
A single ventilation unit can satisfy the amount of

ventilation required for multiple rooms and the entire

building. …………

Natural air
exhaust
Natural air
supply

A

ir exhaust

A

ir supply

(Natural
ventilation)

Fig. 3-1

Warehouses, gymnasiums, factories

where hot air is generated

Class 1 Ventilation Method

Exhaust

Mechanical
exhaust

A

ir

supply

Mechanical air
supply

Indoor

Ventilating fan

Exter­nal air

Ventilating

fan

To be applied for buildings, indoor parking
lots, boiler rooms, electric rooms, machine

rooms

,

kitchens, and warehouses, etc.

Fig. 3-2

Class 1 Ventilation Method

Exhaust

Mechanical
exhaust

A

ir

supply

Mechanical air
supply

Indoor

Ventilating fan

Exter-
nal air

Ventilating

fan

To be applied for buildings, indoor parking
lots, boiler rooms, electric rooms, machine

rooms

,

kitchens, and warehouses, etc.

Fig. 3-2

Class 2 Ventilation Method

Exhaust

Mechanical
exhaust

A

ir

supply

Mechanical air
supply

Exter­nal air

Positive

pressure

Exhaust

outlet

Indoor

Ventilating fan

Fi

g

. 3-3

To be applied for clean rooms and cooling
machinery, etc.

Class 1 Ventilation Method

Exhaust

Mechanical
exhaust

A

ir

supply

Mechanical air
supply

Indoor

Ventilating fan

Exter-
nal air

Ventilating

fan

To be applied for buildings, indoor parking
lots, boiler rooms, electric rooms, machine

rooms

,

kitchens, and warehouses, etc.

Fig. 3-2

Class 2 Ventilation Method

Exhaust

Mechanical
exhaust

A

ir

supply

Mechanical air
supply

Class 3 Ventilation Method

Exhaust

Mechanical
exhaust

A

ir

supply

Mechanical air
supply

Exter-
nal air

Exter­nal air

Positive

pressure

Exhaust

outlet

Indoor

Ventilating fan

Indoor

Fi

g

. 3-3

Negative
pressure

Air supply

inlet

Ventilating

fan

Fi

g

. 3-4

To be applied for clean rooms and cooling
machinery, etc.

To be applied for kitchens, toilets, rooms where hot-water
heaters can be utilized in residences, and copying
rooms, etc.

Air
supply

Contami-

nated air

Ex­haust

Fig. 3-5

 Local ventilation

This type of ventilation is performed for particular spots in a

house (rooms or parts).
a) Local exhaust

Local exhaust is performed for particular places in which

contaminants (combustion gases, humidity, smoke, and

smell, etc.) may be generated (Fig. 3-6).

(Ohmsha, Ltd., Ventilation, the
Society of Heating, Air-Conditioning
and Sanitary Engineers of Japan)

This kind of ventilation is applied

specically for kitchens, bathrooms,
and toilets, etc.

a) Room ventilation

Individualized ventilation designed for single rooms, etc.

(When individualized ventilation systems are installed

in all rooms, the entire setup can be referred to as total

ventilation.)

Cooking o
hood fan

ven

The range

covered b

y

ventilation

Exhaust

Oven

Fig. 3-6

- (01-22) -

4-4. DESIGN PRECAUTIONS

4-4-1. CAUTION ON SAFETY



SAFETY PRECAUTIONS

Described below is what you are supposed to observe to prevent

dangers to the users or other people as well as damage or loss of the

property.



The degrees of danger or damage that is likely to occur due to the

wrong use ignoring the indications are categorized for explanations as

marked below.

DANGER

The column with this mark shows “Impending Danger
of Death or Serious Injury.”

WARNING

The column with this mark shows “Conceivable Threat
of Death or Serious Injury.”

CAUTION

The column with this mark shows “L ikelihood of
Damage or Loss to Materials Only.”

 Kinds of the items to be observed are categorized for clarication

with the following pictorial symbols. (The marks described below

are samples.)

This pictorial indication shows “Prohibited.”

This pictorial indication shows “Forced Execution.”



CAUTIONS FOR INSTALLATION

Do not install, move, or relocate the
unit by yourself without contacting
your dealer or professional installer.

Improper installation could cause
a drop of the unit, an electric
shock, or a fire.

Ask the sales office or the engineer­ing shop to perform the work.
The external air intake opening
should not be positioned where dis­charged air may directly enter it.

A situation like this will lead to the
room being contaminated and
this may pose a health risk.

The external air intake opening
should be positioned away
from the exhaust openings of
combustion gasses.

The intake of such gasses
could lead to a lack of oxy­gen in the room.

WARNING

Prohibited

Install the unit inside the
heat-insulating walls (in the space
insulated from the open air).

If you install it outside (in the space
equivalent to the open-air conditions),
dew is condensed inside the unit body
in the winter season, causing electric
shocks or dew condensation water to
drops, etc.

Install at a stable place of sufficient
strength.

Please note that there might be
some places not strong enough
to install due to the building

structure.
Provide an exclusive circuit
breaker.
Depending on the environment for
installation, it becomes necessary
to install an earth leakage breaker.

Unless the earth leakage

breaker is installed, it could

cause an electric shock.
Ask the sales office of the engi­neering shop to perform the work.

Do not install in locations where
harmful or corrosive gasses may
be present (e.g. acidic, alkali, or­ganic, solvent, paint gasses, etc.
from machinery or chemical plants,
etc.).

Installation in such a location
could cause a gas-poisoning
and a fire.

Carry out GND work.

Never connect the GND wire
to a gas pipe, a water supply
pipe, a lightning conductor, or
a GND line of a telephone,

c. An incomplete GND wire

likely to cause an electric

shock.

et
is

If the unit is accompanied by water
drainage, make sure that the duct
is installed properly.

If it is not installed properly,
the building is likely to be
flooded, wetting the house-

hold effects.
Do not install the unit in locations
with large amounts of oily smoke.

If you use the unit in such a

location, the filter or the heat

exchange element gets

clogged with oily substances,

and unable to be utilized.
Do not install the unit in high
humidity locations, such as bath­rooms.

Doing so may cause an electric
shock or a breakdown of the
unit.

(Excluding any humid-

ity-resistant models)

CAUTION

Insulated Walls

DuctUnit Body

External

A

ir

GND wire

connection

Prohibited

Prohibited

Prohibited

Install the unit inside the
heat-insulating walls (in the space
insulated from the open air).

If you install it outside (in the space
equivalent to the open-air conditions),
dew is condensed inside the unit body
in the winter season, causing electric
shocks or dew condensation water to
drops, etc.

Install at a stable place of sufficient
strength.

Please note that there might be
some places not strong enough
to install due to the building

structure.
Provide an exclusive circuit
breaker.
Depending on the environment for
installation, it becomes necessary
to install an earth leakage breaker.

Unless the earth leakage

breaker is installed, it could

cause an electric shock.
Ask the sales office of the engi­neering shop to perform the work.

Do not install in locations where
harmful or corrosive gasses may
be present (e.g. acidic, alkali, or­ganic, solvent, paint gasses, etc.
from machinery or chemical plants,
etc.).

Installation in such a location
could cause a gas-poisoning
and a fire.

Carry out GND work.

Never connect the GND wire
to a gas pipe, a water supply
pipe, a lightning conductor, or
a GND line of a telephone,

c. An incomplete GND wire

likely to cause an electric

shock.

et
is

If the unit is accompanied by water
drainage, make sure that the duct
is installed properly.

If it is not installed properly,
the building is likely to be
flooded, wetting the house-

hold effects.
Do not install the unit in locations
with large amounts of oily smoke.

If you use the unit in such a

location, the filter or the heat

exchange element gets

clogged with oily substances,

and unable to be utilized.
Do not install the unit in high
humidity locations, such as bath­rooms.

Doing so may cause an electric
shock or a breakdown of the
unit.

(Excluding any humid-

ity-resistant models)

CAUTION

Insulated Walls

DuctUnit Body

External

A

ir

GND wire

connection

Prohibited

Prohibited

Prohibited



CAUTIONS FOR OPERATIONS

Do not use as an air circulators for open-type burners (heaters).

When gas or oil stoves are used in the home, separate equipment for circu­latin

g

the air should be used.

DANGER

Prohibited

When any abnormal condition
(scorching smell, etc.) is found, stop
the operation immediately and keep
the exclusive circuit breaker “OFF.”

If you continue the operation without
removing the cause, it could cause a
mechanical breakdown, an electric
shock, or a fire.

When the system needs a repair,
consult the sales office or the engi­neering shop.
Do not push a finger or stick into the
open-air inlet or the exhaust outlet.

A fan rotating with a high rpm
will injure you.

If combustible gas leaks from
the unit, ventilate the room by
opening windows.

If operation were to be at­tempted in such a situa­tion, sparking at electrical
contact points could cause

an explosion.
Modification of the system is
strictly prohibited.

Improper repair could

cause an electric shock or

a fire.

When the system needs a
repair, consult the sales office
or the engineering shop.
Netting or something similar
should be provided at the ex­ternal air intake opening to
prevent birds, etc. interfering
with the unit.

Nests or other foreign ob-

jects should be removed.

That could lead to a lack of

oxygen in the room.

WARNING

Prohibited

Prohibited

Combustion apparatus should not be
placed allowing a direct exposure to wind
of the unit.

Incomplete combustion could
occur on the apparatus.

Do not blow directly
against animals or
plants.

Likely to cause bad effects on animals
and plants.

Please check the intended uses in
detail for such special purposes as
preservation of foods, flora and
fauna, precision devices, or work of
art, etc.

For special purposes, please conduct
thorough checks in advance.

Otherwise, it could cause deteriora­tion of quality or other problems.

If the unit is not used for a long period
of time, keep the exclusive circuit
breaker “OFF” for safety reasons.

If the power is left on, any
build-up of dust could
cause a heat generation or
a fire.

Do not wash the unit with water.

It could cause an electric
shock.

Do not handle switches with a
wet hand.

It could cause an electric
shock.

Do not use a spray containing
combustible gas near the unit.

It could cause a fire.

Do not use the unit outside
the rated voltage.

It could cause a fire or an
electric shock.

Do not incline the unit when
taking it out.

Otherwise, water re­maining inside is likely to
drop and wet the furniture
or other properties.

() Ask the sales office or the
engineering shop to perform
the work.

CAUTION

Prohibited

Prohibited

Prohibited

Prohibited

Prohibited

Prohibited

Prohibited



CAUTIONS FOR MAINTENANCE

When the filter and the heat exchange element is to be cleaned up, turn the
unit off and keep the exclusive circuit breaker “OFF.”

Cleaning should never be done while the internal fans are running with high
speed. And when using a stepladder, etc., make sure to fix it properly.

WARNING

CAUTION

Do not use benzene or metal brush,
etc., when cleaning the filter and the
heat exchange element.

The filter should be cleaned regularly.

Dust or dirt building-up on it can
lead to a lack of oxygen in the
room.

Use gloves when cleaning the
filter or the heat exchange
element.

Doing so will reduce pos­sibilities of injuries.

Gaso-

Thinner

Prohibited

Otherwise, the unit will get unfit

for use.

Ben-

Metal brush

- (01-23) -



INSPECTION OPENING

Never fail to make the inspection opening at the specic place on the ceiling, so you can perform the constant cleaning,
or the equipment checking of, the lter, the heat exchange element, and the humidier.

 The inspection opening shown below is necessary to clean the heat exchange element and the lter once or twice a year. If

not cleaned, they are likely to get clogged, resulting in deteriorated performance.



Installation Model ……………………



Inspection Opening ……………………

(Exhaust Air)

(Outside Air)

(Room Air)

(Supply Air)

Inspection Opening 450

(For Filter, Heat Exchange
Element, Motor, Damper)

Inside Supply
Opening

Ceiling Suspension Bold

Pipe Hood

Supply Air Duct

Outside Intake
Duct

(Supply

Air)

Room Intake Duct

Room Intake
Opening

Heat Insulation
Material

Exhaust Air Duct

(Exhaust Air)

(Outside Air)

(Room

Air)

4-4-2. INSPECTION OPENING AND INSTALLATION MODELS

- (01-24) -

4-4-3. USE ENVIRONMENTS



DEW CONDENSATION PREVENTION

Our heat exchange unit has been confirmed not to cause dew

condensation water to drop under the following conditions.

If the unit is to be used in severer conditions than the following, dew
condensation water may drop.
JIS B 8628 Total Heat Exchanger Attachment 5 (Regulation) Dew

Condensation Test Methods

nit:˚C

Category

Indoor Conditions Outdoor Conditions

Operation

Conditions

Testing

Time (h)

Dry-bulb

temperature

Wet-bulb

temperature

Dry-bulb

temperature

Wet-bulb

temperature
Cooling in Summer 22±1 17±2 35±1 29±2 On 6
Warming in Winter 20±1 14±2 -5±2 — On 6
Warming in Winter 20±1 14±2 -15±2 — Off 6

In winter, the standard type should be used in the “Heat Exchange”
mode. If it is used in “Normal Ventilation” in winter while the heater
is on, the unit may develop dew condensation, resulting in the
condensation water on the ceiling, which will cause stains, short­circuits in electric wiring, and fault current.

(Caution) Models designed for commercial use cannot be utilized for

residential use due to the different conditions these models

should satisfy. (Otherwise, dew condensation and serious
electric accidents may ensue. If such applications are
inevitable, please contact us in advance.)

(1)

Prevention of Dew Condensation on Product Surfaces



When the humidity and the temperature are high around the product under low
outdoor temperatures, dew may be condensed on the surface of the product.



The following graph indicates marginal conditions for dew condensation on

product surfaces in terms of temperature and humidity around the product, and

outdoor temperature.

Relative Humidity

around Product

Ambient Temperature

around Product

(

)

Preheat

Outdoor Temperature ( )



The product should be used in conditions not exceeding the relative humidity
around the product, as specied in the above graph.

Example 1

When the outdoor temperature is -10˚C and the ambient temperature
around the product is 20˚C, no dew will be condensed until the
ambient relative humidity around the product reaches 40%, as
indicated in the graph. However, when the ambient temperature
around the Product is 25˚C, the ambient humidity around the product
should be less than about 35%, as indicated in the graph.

Example 2

When the outdoor temperature is -10˚C and the ambient temperature
around the product is 20˚C, and if the ambient relative humidity
around the product may uctuate between 40% and 50%, dew may
be condensed on the product surface. In this case, the outdoor
temperature needs to be preheated from -10˚C to -3˚C.

(2)

Prevention of dew condensation on heat exchange
element



As shown in the gure below, suppose a high temp absorbing air condition
A and a low temp absorbing air condition B are plotted on the air line gure,
then a high temp air A is heat-exchanged by the unit and goes out of the
saturation curve as shown by Point C. In this case, the unit will be dewed
or frosted. To avoid this, you are required to heat a low temp air B up to B’
so as to get C’ below the saturation curve, before using the unit.

Absolute humidity (kg/kg’)

Saturation

Curve

Dry-bulb temperature ( )



PREVENTION OF INSECT INTRUSION

The heat exchange unit takes in fresh outdoor air. Thus, if there are
insects in the outdoor environment, they may be sucked in through

the external pipe hood.

Although the unit is equipped with a lter that can trap bigger dust
and dirt, small insects may not be captured by the filter and taken
into the room through the lter perimeters and the frame apertures.
In addition, when the unit is in the “Normal Ventilation” mode and the
operation is stopped, the air course on the exhaust side and indoor
area is connected even though no wind is blowing. In this situation,
intrusion of insects may take place in very rare occasions.
As the emergence of insects may depend on various natural conditions,
we recommend users to apply medium-performance filters (to be
purchased separately) in environments where there are many insects
or where insects are likely to swarm, as the exhaust/intake openings
are close to street lamps, etc. In addition, it is also recommended that
the unit should be turned off in the “Heat Exchange Ventilation” mode.
However, it is almost impossible to completely prevent intrusion of
extremely small insects. Users are thus advised to consider full-scale
insect prevention measures, such as installation of lter boxes (to be
separately purchased by the users) on the designing stage.
When the unit is in operation in the “Normal Ventilation” model, it
should be shifted to the “Heat Exchange Ventilation” mode rst, and
then put to “Stop” after 30 seconds.
The medium-performance lters should be built in the unit, available for
the ceiling-mounted, the ceiling-mounted with a humidier, and the ceiling­suspension cassette types of the products, to be separately purchased.
Although these filters may be equipped after installation of the unit,
please be noted that the supply air volume may be reduced (about 10%).
(The lters are not available for specied and older models.)



PREVENTION OF EXTERNAL

WIND INTRUSION

If the unit is turned off in the Normal Ventilation mode, the external
wind is likely to enter indoors. It is thus recommended to turn off the

unit in the Heat Exchange Ventilation mode.

In cold regions, or areas where frost damages may take place or
strong winds may blow, external winds may enter indoors when
the unit is turned off. In order to prevent these inconveniences, it
is recommended to install an “electric damper (to be separately
purchased by users)” on the side of the external duct.
For ducts with ø100 and ø150, please use the electronic dampers

(electric shutters) we provide; for ducts the diameter of which are

ø200 and ø250, please use those offered by PENTEK.

Contact: PENTEK. (TEL: [phone])



PREVENTION OF SALT EROSION

Our heat exchange ventilation units are not equipped with specific

countermeasures against salt erosion. The following measure may
be proposed, but should require thorough design planning about the
service life of the salt erosion prevention lters, etc.
() In case salt damages need to be prevented in seaside buildings, it is
recommended to install salt erosion prevention lters on the external intake
side (the OA side), which should be separately purchased by users. In this
case, it is necessary to conrm that the designed airow can be secured,
as the intake airow will be reduced by the lter. If it is found that sufcient
airow cannot be obtained, further considerations will be required.
(As for the salt erosion prevention lters, please contact us separately.)



INSTALLING THE UNIT UPSIDE DOWN

The ceiling-mounted model can be installed upside down. (The ceiling­mounted model with humidifying and humidity-resistant types, as
well as the cassette types cannot be installed upside down. For more
details, please check the respective catalogs.)



INSTALLATION LOCATIONS

Do not install the unit body and indoor intake openings in locations
where harmful or corrosive gasses may be present (e.g. acidic, alkali,
organic, solvent, paint gasses, etc. from machinery or chemical plants
and research laboratories, etc.).
(Installation in such a location could cause gas-poisoning, corrosive
deterioration within the unit, and a re.)



ODOR PREVENTION



Water-soluble gasses cannot be used, as they may be freely ferred
with moist, inside the heat exchange element.



Acid gasses cannot be used, as they may be accumulated within the
heat exchange element, and causing damages.



Bathroom (toilet) ventilation facilities should be separately installed.



Although the unit is designed to prevent mixture of fresh external air

and indoor air with packing and sealing materials, it is structurally
difcult to completely prevent such a mixture.

- (01-25) -

4-4-4. HEAT EXCHANGE EFFICIENCY



HOW TO CALCLATE HEAT EXCHANGE EFFICIENCY

The heat exchange efciency can be subdivided into the following

three categories.

Temperature (sensible heat) efciency
Humidity (latent heat) efciency
Enthalpy (total heat) efciency

The heat recovery rate can be calculated if two of the above are
available.
(Temperature efciency and enthalpy efciency are indicated
in catalogs, etc.)
* Each exchange ratio can be calculated in the following formula.

Item Formula

Temperature Exchange

Effectiveness [%]

Temperature Exchange

Effectiveness (%) =

External Air Temperature (˚C) - Internal Supply Air Temperature (˚C)

X 100

External Air Temperature (˚C) - Internal Temperature (˚C)

Enthalpy Exchange

Effectiveness [%]

Enthalpy Exchange
Effectiveness (%) =

External Air Enthalpy (kJ/kg) - Internal Supply Air Enthalpy (kJ/kg)

X 100

External Air Enthalpy (kJ/kg) - Internal Air Enthalpy (kJ/kg)

<How to calculate air conditions after passing through the heat exchange unit>

If the temperature and humidity of the internal air and external air are determined, and if the exchange efciency of the heat
exchange ventilating unit to be utilized is determined, air conditions of the air supplied indoors and exhausted outdoors after
passing through the heat exchange unit can be calculated in the following formula.

Intake Side

Temperature

Internal Supply Air Temperature (˚C) = External Air Temperature (˚C) - (External Air Temperature (˚C) ­Indoor Air Temperature (˚C)) x Temperature Exchange Effectiveness (%)

Enthalpy

Internal Supply Air Enthalpy (kJ/kg) = External Air Enthalpy (kJ/kg) - (External Air Enthalpy (kJ/kg) ­Internal Air Enthalpy (kJ/kg)) x Enthalpy Exchange Effectiveness (%)

Exhaust Side

Temperature

Exhaust Air Temperature (˚C) = Indoor Air Temperature (˚C) - (External Air Temperature (˚C) - Indoor
Air Temperature (˚C)) x Temperature Exchange Effectiveness (%)

Enthalpy

Exhaust Air Enthalpy (kJ/kg) = Indoor Air Enthalpy (kJ/kg) - (External Air Enthalpy (kJ/kg) - Internal Air
Enthalpy (kJ/kg)) x Enthalpy Exchange Effectiveness (%)

Outdoor

Indoo

r

Fresh External Air
(OA)

Stale Indoor

A

ir (RA)

Heat Exchange
Element

Heat-exchanged
Clean Air Taken
Inside

Heat-exchanged
Stale Air Ex­hausted

- (01-26) -



TOTAL HEAT EXCHANGE

In the case of ventilation with the total heat exchange mode, the air condition supplied indoors is at point S; in summer,
precooling is performed from the external air temperature to the indoor intake temperature, and dehumidifying is performed
from the external absolute humidity to indoor intake absolute humidity; and in winter, preheating is performed from the
external air temperature to the indoor intake temperature, and the external absolute humidity is further humidied to indoor
intake absolute humidity prior to being supplied indoors.
When the total heat exchange is utilized, the calorie to be recovered can be calculated in the following formula.

Recovered Total Calorie: qT [w] = (Air Specic Gravity 1.2 [kg/m3]) x (Process Airow [m3/h])

X (External Air Enthalpy (kJ/kg) - Internal Air Enthalpy (kJ/kg)) x Total Heat Exchange Efciency x 0.28 [w·h/kJ]



SENSIBLE HEAT EXCHANGE

The following gure indicates various air conditions when external air is taken in through sensible heat exchange.
In the case of sensible heat exchange ventilation, the recovered calorie can be calculated in the following formula.

Recovered Sensible Heat Calorie: qT [w] = Air Specic Gravity [1.2 kg/m3 in the normal condition] x Process Airow [m3/h]

x Isobaric Specic Heat of Dry Air (1.006 [kJ/kg·°C]) x (External Air Temperature
[°C] - - Internal Air Temperature [°C]) x Sensible Heat Exchange Efciency x 0.28
[w·h/kJ]

1 - Efficiency (%)

Efficiency (%)

A

bsolute Humidity

Condition of Internally
Supplied Air with Heat
Exchange Ventilation Unit

A

bsolute Humidity o

f

External Air

A

bsolute Humidity o

f

Internal Air

Efficiency (%)1 - Efficiency (%)

A

bsolute Humidity of

Internal Air

Condition of Internally Supplied

A

ir with Heat Exchange Venti-

lation Unit

A

bsolute Humidit

y

of External Air

External Air

Temperature

(

)

Indoor Supply
Air Tempera-

ture

(

)

Indoor Tem-

perature (

)

Supply Air

Tempera-

ture ( )

Indoor Tem-

perature (

)

External Air

Temperature

(

)

Dry Bulb Temperature

(

)



Enthalpy

Referring to how many calories are contained in moist air under a certain condition per 1kg of dry air in it, based on the
supposition that the calorie contained in 1kg of dry air at 0˚C is 0 kcal. The unit is kJ/kg.

SI Unit Conversion Table

1kcal/kg = 4.2kJ/kg

1kcal/h = 1.16W

- (01-27) -

4-4-5. DUST COLLECTION EFFICIENCY



DUST COLLECTION EFFICIENCY

Dust collection efciency refers to the efciency of a lter

for collecting dust and dirt. There are various methods

to determine the efciencies, but the following are three

most representative ones.

* Mass ratio method: ····

Certain amounts of dust are

applied to a lter and the collected
volume is evaluated by the mass

ratio. (For rough dust)

* Colorimetric method: ··

Certain amounts of dust are applied

to a lter and the collected volume is
evaluated by the optical transmission

ratio. (Medium performance)

* Counting method (DOP method):
Certain amounts of dust are applied

to a lter and the collected volume is
evaluated by counting the number of

particles. (High performance)

The measuring methods for dust collection efficiencies

are divided into JIS colorimetric method, NBS colorimetric
method, counting method (DOP method), and mass ratio

method (AFI).

High values recorded in the mass ratio method may be

lower ed when converted in the colorimetric method.
Please refer to the indication of the measuring method.



Please refer to the correlation graph below for different dust
collection efciency methods.

Efficiency based on
Mass Ratio Method

Conversion Ratio (%)

Efficiency based on
NBS Colorimetric
Method

Efficiency based
on Counting
Method (DOP)

Efficiency based on JIS Colorimetric Method (%)

For example, “95%” in the mass ratio method may be
indicated as “55%” in JIS colorimetric method.



Correlation among different dust collection efficiency

measuring methods



Although there is no clear correlation among these

measuring methods, the above figure is a conversion
line graph based on approximated values.

- (01-28) -

4-4-6. NOISE



UNIT OF NOISE : DB (DECIBEL)

Sound pressure level with a weight corresponding to the

“A” scale in the noise level meter is referred to the noise
level. The unit is internationally expressed as “dB (A).” In
Japan, JIS regulations stipulate that “dB” or “phon” should
be used. We use “dB” in this catalog.



ACCEPTABLE NOISE LEVEL

Recommended noise levels for indoor regular noises

Facility

Applications

Noise Level

(dB)

Facility

Applications

Noise Level

(dB)

Concert Hall 21-30

Bed Room,

Hospital, Hotel

34-47

Broadcasting

Studio

21-30

Small Theater,

Conference Room

42 or Less

Large Theater,

Church

30 or Less

Factory,

Workshop

66-80

Class Room,

Library

38-47

Lobby,

Laboratory

47-56

Living Room,

Drawing Room

38-47

Restaurant,

Large Ofce

42-52

(Source: Handbook of Noise and Vibration Control)

What is NC curve?

This is a curve to indicate frequency-based acceptable levels,

proposed and utilized for noise evaluations in the U.S.

How to interpret NC curve?

The band level is determined by applying octave analyses
to the target noise, record the results in the NC curve to
determine the maximum NC curve in each band, which shall
be determined as NC value for the target noise.



PRECAUTIONS CONCERNING

NOISE LEVELS

The noise values (dB) of the product indications are

measured at regulated distances in anechoic chambers
as specied in JIS, etc.

The following points should be considered in selecting

proper products.

(1) Changeable due to environmental conditions

The measured values were determined in anechoic

chambers. In real settings, echoes will take place
from walls, floors, ceilings, etc. The measurements
may also increase due to the materials used and the
surrounding space. It is thus necessary to consider
echo coefcients. Noise levels may also be increased
by piping and placement of components.

(2) Propagation of vibration

Although products are designed to minimize vibration,

certain levels of vibration are inevitable, as rotating
mechanisms are contained. It is thus necessary to pay

close attention to the installation methods appropriate
to individual products.

(3) Sound synthesis

When multiple units are to be installed in the same

room, it is necessary to consider sound syntheses.
Particularly when multiple units of the same model are
installed next to each other, “humming” sound may
arise due to slightly different rotations.



Distance decay for sound

When the sound source is sufficiently small in

comparison with distance, or in the case of a point sound
source, by calculating the sound level “r0” (m) at a short
distance, the sound level L0(dB) at a long distance, “r” (m)
is determined as “L = L0 - 20log (r/r0).”



Sound synthesis

The sound level may be expressed as, y = 10log x.
Thus, when L1 and L2 noises are combined, the synthesized

sound level (dB) is “L = 10log (10

L1/10

+ 10

L2/10

).”

- (01-29) -

4-4-7. NOISE CONTROL



CONTROLLING NOISE FROM

EXHAUST/INTAKE OPENING

1. The following components are recommended for a
ceiling-mounted unit.

(1) Noise-reduction duct —— Glass-wool duct

│
└—Noise-reduction exible duct

(2) Noise-reducing intake/exhaust duct

2.

The following option is available for cases in which
the noise reduction measures in “1” above are still
insufcient, or in the case of the ceiling-suspension type.

(1) Highly efcient sound-absorption materials are used

for the interior cover materials.

3.

When the airflow sound is generated at the exhaust/

intake opening in the ceiling-mounted type, the following
options are available, as the sound absorption effects

are higher in ducts with smaller diameters.

(1) Branched ducts (the airow rates at the exhaust/

intake opening are reduced by dividing the ow)

(2) One-rank lower multiple noise-reduction ducts (with

smaller diameters) should be used.



EFFECTS OF NOISE CONTROL

MEASURES

Points

1. The noise-reduction duct (not less than 2m) should

always be used at the exit of the unit on the internal
supply side.

2. Spiral ducts (galvanized steel tubes) and aluminum
exible ducts should not be connected to the unit exit

opening.

General Comparison of Effects

(1) Great Effects –
(4) Small Effects

(1) Noise-reduction duct, installed

for 6m

(2) No is e- re ducti on du ct on th e

side of the unit, installed for 2m

Unit

Noise-reduct

ion duct

(6m)

Intake/Exhaust

Unit

Noise-reduct

ion duct

(2m)

Spiral Duct

(4m)

Intake/Exhaust

Grill

(3) No is e- re ducti on du ct on th e

side of the intake/exhaust grill,

installed for 2m

(4) Spiral duct, installed for 6m (no

noise-reduction measure)

Unit

Spiral Duct

(4m)

Noise-reduct

ion duct

Intake/Exhaust

Grill

(2m)

Unit

Spiral Duct

(6m)

Intake/Exhaust

Grill

Catalog Level

Note: (1)

The noise levels were measured at 1.5m below the intake/exhaust

grill.

(2)

The noise gures are those converted to the level in an anechoic
chamber. In real settings, the levels will be raised due to echoes
and other effects (by about 5dB).

- (01-30) -



CONTROLLING NOISE

GENERATED FROM EQUIPMENT
AND AIR COURSES ABOVE
CEILING AND UNDER ROOF

1.

If noise control is deemed necessary as the unit is

utilized in a quiet place, the following points should be
carefully considered. (Otherwise, noise levels may rise.)

(1) Do not downgrade the duct diameters extremely.

(E.g., ø250 -> ø150, ø200 -> ø100)

(2) Do not bend aluminum exible ducts extremely.

(Particularly, the bending immediately after the exit
opening of the unit body)

(3) Do not make unnecessary openings on the ceilings.

(4)

Do not suspend the unit under members with insufcient

strength.

2.

The following control measures may be taken.

(1) Ceiling materials should be of high sound insulation

quality (with large transmission losses)
<Note>
Specifically, low-frequency noises cannot be

signicantly absorbed by certain ceiling materials.

(2)

Apply additional sound-absorbing materials immediately

below the sound source.

(3)

Cover the unit body entirely with sound insulation sheets.

- (01-31) -

4-5. VENTILATION DESIGN

4-5-1. QUANTITY, DYNAMIC PRESSURE / STATIC PRESSURE

The performance of a ventilation fan can be expressed
by “quantity” and “static pressure.” These two factors are
closely related to each other and constitute prerequisites for
considering “ventilation.” The rst step to “ventilation design”

is to understand these two factors.



QUANTITY (AIRFLOW VOLUME)

This is the airow volume exhausted (or taken in) by a ventilating
fan for a unit time, and generally expressed by m3/h or m3/min.



PRESSURE

This is the force applied by wind on a unit area, and generally
expressed by Pa. The pressure can be subdivided into the

following three categories.


Dynamic Pressure

Pressure derived from wind velocity is referred to as

dynamic pressure or velocity pressure. Windowpanes of
buildings bending under pressure of strong wind in storms
are typical indications of dynamic pressure.



Static Pressure

The pressure working on inated balloons from inside is referred

to as static pressure, which functions even if air is not moving.



Total Pressure

The total pressure is the entire pressure of wind or air,

combining both dynamic and static pressures.



RELATIONSHIPS AMONG

DIFFERENT TYPES OF
PRESSURE

Airflow

Blower

Water-column

Manomete

r

Static

Pressure

Ps Pv

Pt

Dynamic

Pressure

Total Pres-

sure

Fig. 6-1

The airow inside a duct and each type of pressure there can
be illustrated as in Fig. 6-1.

Moving the certain amount of air in the duct will require “Static
Pressure (Ps)” to overcome the resistance within the duct.
“Dynamic Pressure (Pv)” represents the pressure applied
in the direction of the airflow and can be expressed as a
function of the wind velocity, can be used for measuring wind
velocity.
By adding the “Static Pressure” and the “Dynamic Pressure,”
“Total Pressure (Pt)” is generated. This relationship can be

expressed as follows.

V: Flow velocity (m/sec)
g: Gravity acceleration (m/sec2)

: Specic weight of air (kg/m3)



HOW TO INTERPRET STATIC

PRESSURE - QUANTITY
CHARACTERISTIC CURVE
(P-Q CURVE)

A graphic presentation of the relationship between the
quantity and the static pressure of a ventilating fan is referred
to as “P-Q Curve,” which can indicate the performance of the

fan. Fig. 6-2 illustrate a case in which a small intake opening

is installed on a wall, where the indoor pressure is a little

lower than the atmospheric pressure (the static pressure: B

[Pa] and the quantity: B’ [m3/h]), and the ventilator cannot
generate sufcient ventilation volume.

Fig. 6-3 illustrate a case in which a sufficiently large intake
opening is installed on a wall, where the indoor pressure is

almost equivalent to the atmospheric

pressure (the static pressure: O [Pa]
and the quantity: C’ [m3/h]), and the

ven t ilato r can g enera t e suf f icie n t
ventilation volume.

Fig. 6-4 illustrate a case in which the intake

opening is large enough but the ventilating
fan has a certain resistant component, such
as pipe hood, etc. The
quantity (D’ [m3/h])
can be determined by

the intersecting point

made by P-Q curve

and the resistance

loss
curve of the installed
component.

Small
intake

opening

A little lower

than

atmospheric

pressure

Static pressure

(Pa)

* Static pressure:
Point B
* Quantity: Point
B’

B→Quantity (m3/h)

Fig. 6-2

Big
intake
opening

Big intake
opening

Almost
equivalent to
atmospheric

pressure

Almost
equivalent to
atmospheric

pressure

No
differ­ence

* Static
pressure: Zero
* Quantity: Point
C’

B

C’→Quantity (m3/h)

Fig. 6-3

Static pressure

(Pa)

No

* Static pressure:
Pont D
* Quantity: Point
D’

Component

Static

p

ressure

(

Pa

)

Resistance loss
curve

D→Quantity (m

3

/

h)

Fig. 6-4

Big intake
opening

Almost

equivalent to

atmospheric

pressure

No

* Static pressure:
Pont D
* Quantity: Point
D’

Component

Static

p

ressure

(

Pa

)

Resistance loss
curve

D→Quantity (m

3

/

h)

Fig. 6-4

- (01-32) -

4-5-2.

HOW TO CALCULATE REQUIRED VENTILATION VOLUME

To determine ventilation airflow volume, various calculation
methods are available, based on diverse indoor conditions,

such as the volume of CO2 generated by the number of

occupying people, the volume of exhaust gasses generated
by combustion, etc.

It is necessary to specify gures as accurately as possible,
based on the actual conditions in which rooms are utilized.



METHOD BASED ON THE NUMBER

OF VENTILATION OPERATIONS
REQUIRED FOR A ROOM

Required Ventilation Volume (m3/h)
= Number of Ventilation Operations Required in an
Hour (times/h) x Cubic Capacity of Room (m3)

 The ventilation volume can be determined by calculating

the cubic capacity of the room and using the number of
ventilation operations indicated in Table 6-2.

(Example) Location: Bathroom

Required Number of Ventilation Operations:
Five (Times/h)

Cubic Capacity of Room: 6 Jo (about 10m2)

Height of Room: 2.4m

From the above conditions;
Required Ventilation Volume

= 5 x 10 x 2.4 = 120 (m3/h)

It is thus necessary to select a ventilating fan that

can satisfy the above gure.

- (01-33) -

4-6. DUCT DESIGN

4-6-1. CALCULATION OF PRESSURE LOSSES DUE TO VENTILATION

THROUGH DUCT

Ventilation is always conducted through ducts in ventilation
fans for ducts and oven hoods (pressure type). To determine
the ventilation quantity, pressure losses due to the lengths,
the number of bends, and external installation components,
etc., should be accurately calculated, so that proper
ventilation quantities can be determined.



PROCEDURES FROM DUCT

CALCULATION TO MODEL
SELECTION

Equal Pressure Method Simplified Method

Calculation of Required Ventilation Quantity

Duct Design (Duct Diameter, Duct Type, Piping Route,

Length, Bending)

Simplified Method based on “Straight Duct

Equivalent Length”

Method based on “Frictional Resistance

Dia

g

ram”

To determine
ressure loss in the
straight duct with
“Frictional Resis-

ance Diagram.”t

t

To determine the “straight
duct equivalent length” for

he entire duct by using the

straight duct equivalent

length table for the

com

p

onent.

p

To determine the
local pressure loss
with the “local loss

coefficient.”

To determine the intersec-

tion by plotting the “loss
resistance curve” in the
“Static Curve - Quantity

Characteristic Curve.”

To determine the

pressure loss of the

entire duct system.

The required static pressure is determined by adding

10-20% tolerances to the obtained pressure loss.

To select a model satisfying the characteristics with the

“Static Curve - Quantity Characteristic Curve.”

Fig. 7-1



CALCULATION BASED ON

EQUAL PRESSURE METHOD

[1] Circular Duct

(1)

Duct resistance can be calculated from the following formula.

To determine the pressure loss caused in air owing through

a straight duct (ΔP), the following formula is generally used.

Duct Resistance ΔP (Pa) =

: Friction Coefcient of Duct (0.01 - 0.25)

g: Gravitational Acceleration (9.8m/sec2)

: Air Density (kg/m3) 1.20kg/m3

L: Duct Length (m)
d: Duct Diameter (m)

v: Wind Velocity in Duct (m/sec)

v =

3600π

4

d

Q

2

×

Q: Quantity (Airow) (m3/h)
Where, = 0.02 (Galvanized Steel Pipe) = 9.8 = 1.2 is

substituted to produce the following.

P (Pa) = 0.02

9.80665

2

3600π

4

2

d

Q

d

L

9.82

1.2

××××

×



Friction coefcients of common ducts

(references)

Duct Materials

Aluminum exible duct 0.03-0.04

PVC pipe 0.01-0.02

Galvanized steel pipe 0.016-0.025

(2) Method based on “Frictional Resistance Chart of Duct”



Frictional Loss Calculation Chart for Circular Ducts

(Part)

<Galvanized Steel Pipe, Internal Roughness ( ε ) = 0.18mm>

Quantity (Q, Airflow Volume) [m

3

/h]

3

Friction Loss Rate ( ) [Pa/m]
Friction Loss Resistance Chart for Galvanized Steel Pipe

Fig. 7-2

<How to Use Chart>

(Conditions)  Ceiling-Mounted Ventilation Fan

 Required Ventilation Quantity: 300m3/h
 Duct Diameter: ø15cm
 Duct Length: 5m

Quantity (Q, Airflow

Volume) [m

3

/h]

3

Fig. 7-3

Wind Velocity ( )
(m/s)

A

Friction Loss Ratio (Pa/m)

(1)

To determine the intersection (A) of the duct diameter (d)

(15cm) and the quantity of wind running through the duct (Q:
airow) (300m3/h).

(2)

To determine Point (B) by dropping (A) perpendicularly.

(3)

To determine the reading of (B) (2.2 Pa/m in this case), multiply

it with the duct length (5m) to produce 11 Pa.

- (01-34) -

[2] Conversion from Rectangular Duct to Circular Duct

Long Side

De

Equivalent

Diamete

r

Short Side Fig. 7-4



How to use Fig. 7-4

E x ample : A r e c tangu l a r duc t me asuri n g 40 x 20 0

corresponds to a circular duct having a diameter of 90.

1) To determine the intersection (A) of
the short side (40) and the long side
(200).

2) Next, to determine the line (B) going
through the intersection (A), and

determine the intersection (D) with
the diagonal line (C).

The gure (D) indicates the corresponding
diameter, which is 90 in this case.

[3] Local Pressure Loss in Duct

1) Local loss coefcient (also referred to as “local resistance
coefcient”)

At bends or portions where cross sections change, losses

different in nature from those in straight potions will occur

due to eddy currents, etc. These pressure losses in places
other than straight portions can be expressed by the

following formula.

Where, : Local Loss Coefcient

V: Wind Velocity .......................................... [m/s]

* This is the velocity of the upper part of the local

area excluding the merging point.

Pv: Dynamic Pressure ...................................[Pa]

2)

Calculation of pressure loss at a local area in a duct Example:

Consider a case in which the duct bends as follows.

A round bend with the circular

cross section

[Conditions] R/d = 1.5 V = 5.0 (m/s)
From Table 7-1, = 0.15

From the above, P = (Local Loss Coefcient) x Pv (Dynamic

Pressure) = 0.15 x 15 = 2.25 [Pa]

The right side in Table 7-1 indicates the value of the local

pressure loss in this particular part converted to a duct
diameter. ( : Case in which PVC pipe is used)

<Set at 0.018>

le:Straight pipe corresponding length of the local resistance

...

[m]
d: Straight pipe diameter ...[m]
: Local loss coefcient : Duct friction resistance coefcient

Long Side

Short Side

Table 7-1

No. Name

Graphic

Depiction

Conditions

Loss

Coefcient

Length

Corresponding

to PVC Pipe

H/W R/d

1

A round bend

with the circular

cross section

0.5 0.71 39d

0.75 0.33 18d

1.0 0.22 12d

1.5 0.15 8d

2.0 0.13 7d

2

A square bend

with the circular

cross section

0.5

1.2 67d

3

A round bend

with rectangular

cross section

0.5 1.30 72d

0.75 0.52 29d

1.0 0.25 14d

1.5 0.20 11d

1

0.5 1.20 67d

0.75 0.44 24d

1.0 0.21 12d

1.5 0.17 9d



CALCULATION IN SIMPLIFIED

METHOD

 A case in which a model is selected, based on straight

pipe corresponding length and airow quantity A model is
selected, based on the following conditions.

Required ventilation quantity: 120 [m3/h] Duct system: Fig.

7-5 (60Hz)

(Example Problem)

Ceiling-Mounted
Ventilation Fan

Duct Diameter:
100mm
Material: Galvanized
Steel Pipe
( = 0.02)

Fig. 7-5

(Case in which the galvanized steel pipe of = 0.02 is used)

Pipe Hood Bent Cap

Type

Product

Number

Duct

Diameter

Straight Pipe

Corresponding Length

Type

Product

Number

Duct

Diameter

Straight Pipe

Corresponding Length

Stainless Steel

(Rectangular)

FY-WKX042

ø100mm 5m

Stainless Steel

FY-VCX042

ø100mm 2m

FY-WKX062

ø150mm 12m

FY-VCX062

ø150mm 4m

Stainless Steel

(Round)

FY-MCX042

ø100mm 9m

Stainless Steel

(Accompanied by

an insect net)

FY-VNX042

ø100mm 5m

FY-MCX062

ø150mm 13m

FY- VNX062

ø150mm 7m

Stainless Steel

(Accompanied by

a re damper)

FY-MCXA042

ø100mm 12m

Stainless Steel

(Accompanied by

a re damper)

FY-VCXA043

BL

ø100mm 8m

FY- MCXA062

ø150mm 13m

FY-VCXA063

BL

ø150mm 7m

Aluminum (Round)

FY-MCA042

ø100mm 9m

Aluminum

FY-VCA042

ø100mm 2m

FY-MCA062

ø150mm 13m

FY-VCA062

ø150mm 3m

Aluminum

(Accompanied by

an insect net)

FY-MNA042

ø100mm 15m

(R/d = 1.0) Elbow

ø100mm 2m

FY-MNA062

ø150mm 32m ø150mm 3m

Table 7-2



Table 7-2 is used to convert

the resistance at each
component of the duct to
the straight pipe length.

Table 7-3



Static Pressure - Quantity Characteristic Curve



To select an appropriate model.

Case in which a model satisfying

the straight pipe corresponding

length: 19 [m] and the airflow
quantity of 130 [m3/h]

A perpendicular line is dropped
from the intersection (A) made

by the resistance curve of the 19
[m]-pipe and the static pressure

- quantity characteristic curve to
determine the point (B), and the
model to be selected should satisfy
the value at the point, that is, 130

[m3/h].

Piping

Portion

Length of Corresponding Straight

Pipe (Diameter: 100mm)
I 0.5m
II 2m

III 0.5m
IV 2m
V 5m
VI 9m

Total 19m

Pipe Resistance

Curve

Airflow Quantity (m3/h)

- (01-35) -



MODEL INSTALLATION (FOR

CEILING-MOUNTED TYPE

)

Installation of Unit Body

 You are required to prepare the

ceiling suspension bolts, nuts,

and washers.

 Install th e un it fi rmly an d

horizontally to support its weight
sufciently. (Fig. 1)

 If you do not fit it firmly, it is

not only dangerous but also
easily vibrated. If it is not tted
horizontally, the damper unit
becomes defective in operation.

Caution

 When you are required to be cautious particularly on

prevention of vibration, we recommend you to use the anti­vibration ceiling suspension xtures. (Fig. 2)

 Never fail to make an inspection opening with � 450mm or

more at the specied place, so that you can inspect lters, heat
exchange elements, power source, and motors.

Cautions on Installing the Unit Body Upside Down



Re-fit the ceiling suspension

xtures in the opposite side. (If they
are left as they are, the foolproof
function of ceiling suspension bolts

does not work and will cause the
danger of dropping the unit.)



Printed indication is in a reversed

position. In particular, be careful
of the arrow mark “↑” showing

the direction of inserting the heat
exchange element.

Note: The above provisions apply only to those models that allow

reverse installation.



DUCT INSTALLATION

 Wind the junction of an adaptor and a duct with an aluminum

tape rmly to prevent any air leakage.

 The room intake opening should be positioned as far as

possible away from the inside supply opening.

 Use the specied ducts with the diameters appropriate for the

unit.

 Install two outdoor ducts, so they will be in the down gradient

toward outside to prevent water from coming in. (Gradient:1/100

- 1/50) (Fig. 3)

 Never fail to heat-insulate two indoor ducts (including intake

and exhaust air ducts) to prevent dewing. (Material: Glass

Wool, Thickness: 25mm) (Fig. 3)

 When you want to piece the metal duct through the metal lath

or the wire lath or the metal plate of the wooden facility, do not
forget to insulate electrically between the duct and the wall.
(Please refer to the electric facility engineering standards and

the internal regulations.)

Heat Insulation Material (to
insulate the Adapter and
Aluminum Tape)

Outside Intake Duct, Exhaust Air Duct

Gradient

Aluminum
Tape

Aluminum Tape

Fig. 3

Ceiling Suspen-

sion Bolt

Nut

Washer

Ceiling
Suspension
Fixture

Washer

Nut

Fig. 1

Ceiling Suspen-

sion Bolt

Ceiling Suspen-

sion Bolt

Nut

Washer

Ceiling
Suspension
Fixture

Washer

Nut

Fig. 1

Anti-Vibration
Ceiling
Suspension
Fixture

Unit Body

Fig. 2

Unit installed upside down

Insulation
Material

Hexagon
Bolt

Unit Body

One or
two bolts

Cautions for duct piping

<When collective ducts are used>

In an installation layout as in Fig. 4, do not operate the heat

exchange unit A alone.

When the heat exchange unit B stops operation, air is reversed
from SA (intake opening), reducing the fresh external air, and
deteriorating the ventilation efciency.
In this case, an electric damper should be installed in the duct
piping (please refer to Fig. 5), so that the opening/closing
functions can be mechanically controlled.

Electric
Damper

Electric
Damper

Heat
Exchange
Ventilation
Unit A

Fig. 4 Fig. 5

Heat
Exchange
Ventilation
Unit B

Heat
Exchange
Ventilation
Unit A

Heat
Exchange
Ventilation
Unit B

Electric
Damper

Electric
Damper

Heat
Exchange
Ventilation
Unit A

Heat
Exchange
Ventilation
Unit B

 The intake and exhaust openings on the external walls should

generally be distanced from each other by about three times

the duct diameter to prevent short circuits.

 Vibration prevention is basically unnecessary. (If anti-vibration

ceiling suspension xtures are required, please use FY-BG71 -

BG74).

 Install the ceiling-mounted and ceiling-suspension types

horizontally. (Otherwise, damper may not function properly.)

 For the ceiling-mounted type, install an inspection opening at a

specied location to check the heat exchange elements, lters,
and wind blower.



Refrain from using the following duct
installation works.

(1) Excessive bending (2) Multi-times bending

(3) Making the connecting duct smaller