VALLOX 252 D removes contaminated air
and replaces it with filtered and heated
outdoor air.
Efficient filtering of outdoor air
(EU3 + EU7) prevents harmful particles
from entering the ductwork and the rooms
via the unit. Good filtering of extract air
(EU3 + EU5) diminishes the contamination
of the unit and ensures effective operation
of heat recovery and the extract air fans.
Clogging of the supply/extract air filters
and the ductwork can be monitored if the
unit is equipped with a pressure
difference switch.
With efficient 2-step heat recovery, most
of the heat of contaminated extract air
can be transmitted to outdoor air coming
inside. The efficiency of the heat recovery
cells is approx. 70%, or 75…80% if
supply air fan heat is taken into account.
If outdoor air does not get sufficiently
warm in the heat recovery cells, it is
possible to use an (optional) heating unit
operated by water or electricity.
The unit features an automatic heat
recovery bypass function, which
eliminates needless heating of outdoor air
in the summertime. The unit also includes
an automatic defrosting function of the
water operated post-heating unit.
The automatic defrosting of the heat
recovery cells intermittently stops the
supply air fans when the temperature of
exhaust air goes under the preset
threshold value. To avoid or to decrease
the stopping of the supply air fans, you
can heat outdoor air with an electric
preheater. If the unit is equipped with a
preheater, defrosting starts when outdoor
air temperature goes below ca. -15/
-25˚C (max./min. supply air flow).
Without preheating, defrosting starts
when outdoor air temperature falls below
ca. -5˚C.
VALLOX 252 D can be controlled with the
control panel coming with the unit (3 at
most) and with optional CO
and %Rh sensors (2 at most).
Fan speeds can be monitored remotely
with current or voltage signals. In case of
failures in the ventilation unit, a potentialfree relay point signal is received.
The optional VALLOX LON converter
allows remote monitoring based control of
the unit.
(5 at most)
2
610 +
oor and insulation 55m
(D
8
1
1370
13
5
4
14
12
3
VALLOX 252 D-L
A
= OUTDOOR AIR
B
= SUPPLY AIR
C
= EXTRACT AIR
D
= EXHAUST AIR
Silencer
Installed above the unit
)
m
A
B
C
9
2
16
* Detachable inner coupling
187
222
1100
282
*
Ø250 4pcs
17
222
D
220
11
7
6
15
18
10
187
220
Main Parts
1
Supply air fans
2
Extract air fans
3
Heat recovery cells
Heat recovery bypass
4
5
Supply air filter EU7
6
Extract air filter EU5
7
Extract air filter EU3
8
Outdoor air filter EU3
9
Condensing water reservoir
1010
Condensing water outlet
11
Electrical connection
lead-throughs
12
Control panel
Options
13
Post-heating unit
• Electric or water
14
Preheater
• Electric
Pressure difference switch
222
15
16
Carbon dioxide sensor
Humidity sensor
17
LON converter
18
1100
282
222
187
Ø 250 4 pcs
2370
VALLOX 252 D-R
A
= EXHAUST AIR
B
= EXTRACT AIR
C
= SUPPLY AIR
D
= OUTDOOR AIR
665
220
220
1000
1370
187
2
2
Page 3
VALLOX 252 D
PERFORMANCE
VALLOX 252 DVALLOX 252 D
Measuring
points
FAN CAPACITY
Supply air Extract air
E
S
E
S
E
Pressure loss in ducts. Total pressure
S
Fan curves: E = Extract air fan, S = Supply air fan
VALLOX 252 D + silencer
S
E
S
E
S
FAN CAPACITY
SE
E
S
E
Volume flow rate
Recommended
operating range
S
HRC 2
HRC 1
E
Measuring points after the outlet collar.
HRC=Heat Recovery Cell
Fan curves indicate the total pressure
available for duct losses.
Fan speeds
Control
voltage
1
2
3
4
5
6
7
8
V
90
100
110
130
140
160
200
230
flow
(l/s)
110
135
150
175
205
230
Input
Air
power
W
200
80
230
95
275
350
390
450
590
675
VALLOX 252 D + silencer
Measuring points
Supply air Extract air
Pressure loss in ducts. Total pressure
SE
S
E
S
E
S
E
S
E
S
E
S
E
S
E
S
Recommended
operating range
Measuring points after the outlet collar.
HRC=Heat Recovery Cell
HRC 2
HRC 1
E
Fan curves indicate the total pressure
available for duct losses.
Volume flow rate
Fan curves: E = Extract air fan, S = Supply air fan
Fan speeds Control
voltage
V
1
90
2
100
3
110
4
130
5
140
6
160
7
200
8
230
Air
flow
(l/s)
74
85
99
127
143
170
206
220
Input
power
W
200
230
275
350
390
450
590
675
3
Page 4
SOUND VALUES
VALLOX 252 D
• Sound power levels in the ducts measured in accordance
with the standard ISO/DIS 5135:1995.
2
• Sound pressure levels in the room (10 m
sound
absorption) determined according to the regulation
4873/531/84 issued by the Finnish Ministry of
Environmental Affairs.
Medium
frequency
of the
octave band,
Hz
LwA dB(A)
Sound power level from VALLOX to supply
air ducts by octave band Lw, dB
CONTROL POSITION / AIR FLOW l/s
1
76 l/s
Hz
62.0
63
55.0
125
48.0
250
36.0
500
1000
2000
4000
8000
Lw, dB
38.5
28.5
20.0
63.0
44.0
Sound power level coming from VALLOX through the
envelope to the rooms where the unit has been installed
CONTROL POSITION / AIR FLOW l/s
1
78/85
4
138 l/s
65.5
60.0
55.5
44.5
43.5
38.5
30.0
20.0
66.5
50.5
4
129/139
6
169 l/s
68.0
63.5
61.0
49.5
47.0
45.0
35.0
27.0
70.0
55.5
6
166/176
8
212/217
8
208 l/s
69.5
67.0
64.5
54.5
50.0
50.0
39.5
32.0
72.0
59.0
Sound power level from VALLOX to
extract air ducts by octave band Lw, dB
CONTROL POSITION / AIR FLOW l/s
1
4
6
85 l/s
63.0
59.0
47.5
36.5
36.0
28.0
15.5
64.5
45.0
141 l/s
68.5
66.0
57.0
43.5
43.5
38.5
28.5
18.5
70.5
53.5
179 l/s
72.0
68.5
61.0
48.0
48.0
45.0
34.0
27.0
74.0
57.0
8
226 l/s
74.5
72.0
66.0
52.0
49.5
49.5
38.0
31.0
77.0
61.0
VALLOX 252 D
LpA, dB(A)
LpA = A-weighted sound pressure level (10 m
Hz
63
Medium
frequency
of the
octave band,
Hz
LwA = A-weighted sound pressure level
* = difference between sound power level and pressure level when unit location and total absorption
125
250
500
1000
2000
4000
8000
Lw, dB
LwA dB(A)
Sound power level coming from VALLOX through the
envelope to the rooms where the unit has been installed
74/82
LpA, dB(A)
LwA, dB(A)
area are taken into account (e.g. in a classroom, L
40
44
33
Sound power level from VALLOX to supply
air ducts by octave band Lw, dB
CONTROL POSITION / AIR FLOW l/sCONTROL POSITION / AIR FLOW l/s
1
77 l/s
55.0
52.0
33.0
18.0
13.5
14.0
57.0
35.5
4
133 l/s
61.0
57.5
40.5
27.5
16.0
62.5
41.0
47
2
sound absorption)
6
169 l/s
209 l/s
63.0
60.0
46.5
35.0
25.0
19.0
65.0
44.5
8
66.5
62.5
50.5
41.5
32.0
27.0
15.5
68.0
48.0
Sound power level from VALLOX to
extract air ducts by octave band Lw, dB
1
4
80 l/s
55.5
53.5
34.0
57.5
37.0
135 l/s
59.5
59.0
43.0
25.5
17.0
62.5
42.5
6
167 l/s
63.0
62.5
48.0
31.0
24.5
20.5
65.5
46.5
VALLOX 252
CONTROL POSITION / AIR FLOW
4
1
32
36-*
131/138
38.5
42.5-*
6
167/175
43
47-*
8
208/221
46.5
50.5-*
A -* = 12 dB)
w
+ SILENCER
204 l/s
67.0
65.0
51.5
36.5
30.0
27.0
18.5
69.0
49.5
8
4
Page 5
VALLOX 252 D
Pressure loss in the water radiator
The recommended area of operation is ruled. Determined for 100% water.
Total pressure loss kPa
WATER RADIATOR PERFORMANCE
Radiator + valve (KVS 1.0)
Radiator
Water radiator capacity
Temperature of water entering the radiator (tv) 70˚C
Temperature of air entering the radiator (ti) 15˚C
Water flow dm
Total radiator capacity kW
dm3/s
3
/h
dm
Water flow
Temperature of water entering the radiator (tv) 55˚C
Temperature of air entering the radiator (ti) 15˚C
3
/s
Air flow dm
3
/s
Total radiator capacity kW
Water flow dm
3
/s
Air flow dm
3
/s
Cooling of water in the radiator ˚C
Cooling of water in the radiator ˚C
5
Page 6
VALLOX 252 D
CONTROL DIAGRAM VALLOX 252 D
HRC 1
TE1
LP1
switch
Preheater,
electric
TZ1 TZ2
Pressure
difference
PDS2
PF
HRC 2
VALLOX 252 D
Internal electricity and control connections
TE3
FG
switch
Pressure
difference
M
TF
PDS1
EU 3
CONVERTER
LON
Post-heating
EU 7
LP2
TZ2
TZ1
EU 5
EU 3
TE2
unit, electric
230 V
Distribution panel
Separate 16A power supply for preheating
Control diagram VALLOX 252 D
16 A
2 x 16A if resistor capacity exceeds 2.5kW
M
VENTILATION ZONE
CO
Control panel (max. 3 pcs)
Humidity sensor
Fireplace switch
2
sensor (max. 5 pcs)
Booster switch /
S
CO
212
2
CO
2
H
1
H
%RH
1
%RH
2
TE4
SILENCER
ALARM
RUNNING MODE
CONTROL
MEASUREMENT
REGULATION
REMOTE MONITORING CENTER OF THE PROPERTY
6
2
Page 7
VALLOX 252 D
DESCRIPTION OF OPERATION VALLOX 252 D
Control of operation
If needed, power supply to the unit can be controlled via the contactor in
the distribution panel, using a timer program, for instance. Upon starting,
the unit operates at minimum capacity. After that, capacity is controlled
on the basis of measurement data supplied by the air quality sensors
and/or through manual control on the control panel.
Fan speed adjustment
Manual control
Fan speed of the ventilation unit is controlled in 8 steps on the control
panel (H).
Carbon dioxide and humidity control
The fan capacity of the ventilation unit is controlled in multiple steps
depending on load, and based on the measuring results of the air quality
sensors (CO2 and %RH sensors) located in the ventilation zone. The aim is
to keep the CO2 and/or humidity content of the zone below the setpoint
defined on the control panel (H). One or more modes of control may be
used simultaneously. The dominant mode is the one demanding boosting.
Ventilation can be adjusted in a maximum of 8 steps. The basic and
maximum fan speeds for adjustment purposes can be set at the desired
level.
Voltage and current signal control
The fan capacity of the ventilation unit is controlled in 8 steps with the
voltage signal 0…10 VDC, or with the current signal 0…20 mA. However, the fan capacity cannot be raised above the preset fan speed.
The voltage or current signal control is used to control basic fan speed.
Because of this, fan speed can only be raised, but not lowered by the
manual, CO
and %RH controls.
2
Supply air temperature
Supply air temperature can be controlled using either constant temperature control or cascade control.
The control unit directs the operation of the post-heating unit (LP2) on the
basis of the measuring data on the temperature sensor TE2, aiming at
keeping supply air temperature at the temperature value set on the control
panel H (+10˚…+30˚C).
Supply air cascade control
The control unit directs the operation of the post-heating unit (LP2) on the
basis of the measuring data on the extract air sensor TE4, aiming at keeping extract air temperature at the temperature value set on the control
panel H (+10˚…+30˚C).
Heat recovery bypass
When post-heating has been switched on, heat recovery is enabled all
the time. Automatic heat recovery bypass is active whenever post-heating
has been switched off and outdoor temperature is more than the preset
threshold value (range 0˚…+25˚C). In this case, the control unit directs
the operation of the damper motor (FG) on the basis of measuring results
given by the outdoor sensor TE3 and the extract air temperature sensor
TE4. The aim is to get as cool supply air to the ventilation zone as possible.
However, heat recovery is in use whenever outdoor air descends below
the preset threshold value.
Heat recovery anti-freezing
The control / regulation center of the unit directs the operation of the
preheater (LP1) on the basis of the measurement data supplied by the
temperature sensor TE1. The aim is to prevent the risk of freezing and the
stopping of the supply air fan (TF). If the capacity of the preheater (LP1) is
not sufficient, or if there is no preheater, the control center intermittently
stops the TF supply air fan on the basis of the measuring data on the
temperature sensor TE1, thereby preventing the heat recovery cell from
freezing. As soon as the risk of frosting passes, the fan restarts
automatically. The threshold temperature for defrosting (-6…+15˚C) and
the difference area (+1…+10˚C) can be set on the control panel (H).
Overheating protection of the heating unit
The overheat protection thermostats TZ1 and TZ2 monitor the surface
temperature in the LP1 and LP2 heating units. If surface temperature
exceeds the threshold, overheat protection is triggered and power supply
to the heating unit is stopped. The TZ1 overheating protector is reset
automatically, and the TZ2 protector manually.
Alarms
The pressure difference switches PDS1 and PDS2 monitor the pressure
difference between the supply and extract air sides. If the pressure
difference rises too high because of dirty filters or clogged ducts, an
alarm will be issued, showing as a symbol (
control panel. If the unit is not equipped with pressure difference switches,
the symbol (
of the need of servicing the unit. The maintenance reminder interval can
be set between 1...15 months. The factory setting is 4 months. This
function is always active.
The fault signal relay in the unit gives potential-free alarm indications on
the following fault conditions:
• Alarm of high carbon dioxide content (> 5000 ppm ) switches the relay
at 1-second intervals.
• In other fault situations, such as sensor faults and filter guard (
the points of the relay close.
) appearing in the main display of the control panel reminds
) in the main display of the
) alarms,
Booster or fireplace switch function
An extra switch S may be connected to the connection box of the ventilation unit to work as a booster or fireplace switch. The operation of the
switch is selected on the control panel H. The booster switch function raises fan speed to maximum speed for 45 minutes.
The fireplace switch function stops the extract air fan for 15 minutes, and
causes overpressure in the ventilation zone.
LON remote monitoring control can be implemented with the VALLOX LON converter.
Parts list
Code NameTechnical details Note!Equipment
CO2CO2 sensor, max. 5 pcsAdjustment range 500...2000ppm (900)Option
Carbon dioxide controlAdjustment interval 1...15 min. (1)
FGDamper motorAutomatic heat recovery bypass 24V, 2W, 8Nm StandardX
HControl panel, max. 3 pcsSetting, operation, displayStandard, 1 pcX
SBooster / fireplace switchFunctions as either a booster or a fireplace switch StandardX
Pressure guard for supply air
PDS2 Pressure difference switchAdjustment range 0...500Pa (420)Option
Pressure guard for extract air
PFExtract air fanqv = 230 dm
%RH Humidity sensor, max. 2 pcsAdjustment range 1...99% (50)Option
Humidity controlAdjustment interval 1...15 min. (1)
SUFilterSupply air EU7, extract air EU5StandardX
TE1Temperature sensorExhaust air temperatureStandardX
Heat recovery defrosting,Adjustment range -6˚...+15˚C (HRC)
preheating controlAdjustment range -6˚...+15˚C (preheating)
TE2Temperature sensorSupply air temperatureStandardX
TE3Temperature sensorOutdoor air temperatureStandardX
TE4Temperature sensorExtract air temperatureStandardX
TFSupply air fanqv = 210 dm
TZ1Overheat protector Automatic reset (+60˚C)Included
of the heating unit Self-resettingin LP1 / LP2
TZ2Overheat protectorManual reset (+95˚C)Included
of the heating unitin LP1 / LP2
(factory settings in parentheses)
(booster switch)
3
/s (100Pa)StandardX
3
/s (100Pa)StandardX
7
Page 8
VALLOX 252 D
CONTROL DIAGRAM VALLOX 252 D VKL, with water radiator
HRC 1
TE1
TE1
LP1
switch
electric
TZ1 TZ2
Pressure
difference
Preheater,
PDS2
PF
HRC 2
VALLOX 252 D
Internal electricity and control connections
TE3
FG
switch
Pressure
difference
M
TF
PDS1
EU 7
EU 5
EU 3
CONVERTER
Post-heating
unit, water
LP2
EU 3
TE2
radiator (VKL)
SV
LON
230 V
Control diagram VALLOX 252 D
Distribution panel
16 A
M
VENTILATION ZONE
CO
Control panel (max. 3 pcs)
Humidity sensor
2
sensor (max. 5 pcs)
Booster switch /
Fireplace switch
S
CO
2
2
CO
12
2
H
1
H
%RH
1
%RH
2
TE4
SILENCER
Ljm
Ljp
REMOTE MONITORING CENTER OF THE PROPERTY
ALARM
RUNNING MODE
CONTROL
MEASUREMENT
REGULATION
8
2
Page 9
VALLOX 252 D
DESCRIPTION OF OPERATION VALLOX 252 D VKL, with water radiator
Control of operation
Power supply can be controlled via the contactor in the distribution panel,
using a timer program, for instance. Upon starting, the ventilation unit
uses minimum power, and after that power is controlled on the basis of
measurement data given by air quality sensors and/or through manual
control on the control panel.
Fan speed adjustment
Manual control
Fan speed of the ventilation unit is controlled in 8 steps on the control
panel (H).
Carbon dioxide and humidity control
The fan capacity of the ventilation unit is controlled in multiple steps depending on load, based on the measuring results of the CO2 and RH sensors located in the ventilation zone. The aim is to keep the CO
humidity content of the zone below the setpoint that has been defined on
and /or
2
the control panel H. One or more modes of regulation can be used at the
same time. The dominant mode is the one demanding boosting. Ventilation can be adjusted in a maximum of 8 steps. The basic and maximum
fan speeds can be set at the desired level on the control panel H.
Voltage and current signal control
The fan capacity of the ventilation unit is controlled in 8 steps with the
voltage signal 0…10 VDC, or with the current signal 0…20 mA. However, fan capacity cannot be set above the preset maximum fan speed
when automatic adjustments are active. The voltage or current signal control is used to control basic fan speed. Because of this, fan speed can only
be raised, but not lowered by the manual, CO
Supply air temperature can be controlled using either constant temperature adjustment or cascade adjustment.
Supply air constant temperature control
The control unit directs the operation of the control valve (SV) on the basis
of the measuring data on the temperature sensor TE2. The aim is to keep
supply air temperature at the temperature value set on the control panel H
(+10…+30˚C).
Supply air cascade control
The control unit directs the operation of the control valve (SV) on the basis
of the measuring data on the extract air sensor TE4. The aim is to keep
extract air temperature at the temperature value set on the control panel H
(+10…+30˚C).
Heat recovery bypass
When post-heating has been switched on, heat recovery is enabled all
the time. Automatic heat recovery bypass is active whenever post-heating
has been switched off and outdoor temperature exceeds the preset
threshold (range 0˚…+25˚C). In this case, the control unit directs the
operation of the damper motor (FG) on the basis of measuring results given
by the outdoor sensor TE3 and the extract air temperature sensor TE4. The
aim is to get as cool supply air to the ventilation zone as possible.
However, heat recovery is in use whenever outdoor air goes below the
preset threshold.
Heat recovery anti-freezing
The control / adjustment center of the unit directs the operation of the
preheater (LP1) on the basis of the measurement data supplied by the
temperature sensor TE1. The aim is to prevent the risk of freezing and the
stopping of the supply air fan (TF). If the capacity of the preheater (LP1) is
not sufficient, or if there is no preheater, the control center intermittently
stops the TF supply air fan on the basis of the measuring data on the
temperature sensor TE1, thereby preventing the heat recovery cell from
freezing. As soon as the risk of frosting passes, the fan restarts
automatically. The threshold temperature for defrosting (-6…+15˚C) and
the difference area (+1…+10˚C) can be set on the control panel (H).
Overheating protection of the heating unit
The overheat protection thermostats TZ1 and TZ2 monitor the surface
temperature in the LP1 heating unit. The indication of a freezing risk
appears in the display of the control panel. The TZ1 overheating protector
is reset automatically, and the TZ2 protector manually.
Antifreeze protection of the water radiator
On the basis of the measuring data of the outdoor air temperature sensor
TE3 (outdoor air < 0 ˚C) and of the supply air temperature sensor TE2
(supply air < 7 ˚C), the control / adjustment center of the unit stops the TF
and PF fans. This is done in order to prevent the freezing of the water
radiator LP2. The indication of a freezing risk ("Freezing alert) appears in
the display of the control panel. The fans automatically restart as soon as
the risk of freezing has passed (supply air > 10˚C).
Alarms
The pressure difference switches PDS1 and PDS2 monitor the pressure
difference between the supply and extract air sides. If the pressure
difference rises too high because of dirty filters or clogged ducts, an
alarm will be issued, showing as a symbol (
control panel. If the unit is not equipped with pressure difference switches,
the symbol (
) appearing in the main display of the control panel reminds
of the need of servicing the unit. The reminder interval can be set between
1...15 months. The factory setting is 4 months. This function is always
active. The fault signal relay in the unit gives potential-free alarm
indications on the following fault conditions:
• During water radiator anti-freezing, the relay points close and open at
10-second intervals.
• An alarm of high carbon dioxide content (>5000 ppm) switches on the
relay at 1-second intervals.
• In other fault situations, such as sensor faults and filter guard (
the points of the relay close.
Booster or fireplace switch function
An extra switch S may be connected to the connection box of the
ventilation unit to work as a booster or fireplace switch. The operation of
the switch is selected on the control panel H. The booster switch function
raises fan speed to the preset maximum speed for 45 minutes.
The fireplace switch function stops the extract air fan for 15 minutes, and
causes overpressure in the ventilation zone.
LON remote monitoring control can be implemented with the VALLOX LON converter.
Parts list
Code NameTechnical details Note!Equipment
CO2CO2 sensor, max. 5 pcsAdjustment range 500...2000 ppm (900)Option
Carbon dioxide controlAdjustment interval 1...15 min. (1)
FGDamper motorAutomatic heat recovery bypass 24 V, 2 W, 8 Nm StandardX
HControl panel, max. 3 pcsSetting, operation, displayStandard, 1 pcX
SBooster / fireplace switchFunctions as either a booster or StandardX
LONLON converterRemote monitoring control Option
LP1PreheaterElectric radiator 2.5 kWOption
LP2Post-heating unitWater radiator 5kW, 70/50˚COption
HRC1 Heat recovery cells2-step, h = 70 %StandardX
HRC2
PDS1 Pressure difference switchAdjustment range 0...500 Pa (420)Option
Pressure guard for supply air
PDS2 Pressure difference switchAdjustment range 0...500 Pa (420)Option
Pressure guard for extract air
PFExtract air fanqv = 230 dm
%RH Humidity sensor, max. 2 pcsAdjustment range 1...99 % (50)Option
Humidity controlAdjustment interval 1...15 min. (1)
SUFilterSupply air EU7, extract air EU5StandardX
SVActuator valve unit 230 V, open when deadOption
TE1Temperature sensorExhaust air temperatureStandardX
Heat recovery defrosting Adjustment range -6...+15˚C (HRC)
preheating controlAdjustment range -6...+15˚C (preheating)
TE2Temperature sensorSupply air temperatureStandardX
TE3Temperature sensorOutdoor air temperatureStandardX
TE4Temperature sensorExtract air temperatureStandardX
TFSupply air fanqv = 230 dm
TZ1Overheating protector Automatic reset (+90˚C)Included
of the electric radiatorSelf-resettingin LP1
TZ2Overheating protector Manual reset (+95˚C)Included
of the electric radiator in LP1
(factory settings in parentheses)
a fireplace switch (booster switch)
3
/s (100 Pa)StandardX
3
/s (100Pa)StandardX
) in the main display of the
) alarms,
9
Page 10
MOUNTING INSTRUCTIONS
1
8
610 +
(door and insulation 55 mm)
A
B
1370
4
3
7
2
1
22
1
0
0
2
8
2
2
*
2
pcs
50 4
2
Ø
C
2
18
7
D
220
220
1
VALLOX 252 D
Location of VALLOX
• The unit is mounted indoors, in a place where temperature does not fall below
+10˚C.
• The unit shall be mounted in a place where the sound pressure level coming
through the envelope is not acoustically disturbing (storerooms, halls, utility rooms,
and in some cases rooms where people spend a lot of time, such as classrooms).
• The unit is equipped with an adjustable socle. If the unit is mounted on a wall,
observe the weight of the unit (210kg) and vibration damping.
• The unit is splash-proof (IP34), so it can also be mounted in a damp room.
VALLOX duct connections
• The unit has four ø250 inner fittings equipped with rubber rings. The inner fittings
can be detached and replaced with another type of fitting, such as bend or scale
ring. Fix the ducts steadily and tightly to the joints. (Note! Models L/R.) Duct
isolation, if any, is done in accordance with the ventilation plan.
2
VALLOX 252 L
A
= OUTDOOR AIR
B
= SUPPLY AIR
C
= EXTRACT AIR
D
= EXHAUST AIR
VALLOX 252 R
A
= EXHAUST AIR
B
= EXTRACT AIR
C
= SUPPLY AIR
D
= OUTDOOR AIR
1
Cable glands with draught-limiters (PG 16)
2
Condensing water outlet
3
Condensing water reservoir
4
Socle
VALLOX condensing water connections
• The water condensing from extract air going through the unit can be removed from
the bottom reservoir in two ways.
• When extract air humidity is great, as in the bathroom, the condensing water is led
via a screw-type hose coupling and through the condensing water outlet (water
seal and hose) delivered with the unit to the floor drain.
• When extract air humidity is low, as in an office, condensing water can be led via
the screw-type hose coupling to the condensing water reservoir delivered with the
unit. The reservoir is placed under the bottom reservoir by pushing it to the rails on
the socle. In this case, a separate condensing water outlet is not used. NOTE! If a
condensing water reservoir is used, it must be inspected sufficiently often.
• As the screw-type hose coupling is located almost in the middle of the unit, the unit
has to be located in a horizontal position.
VALLOX tube connections
• If the unit is equipped with a water post-heating unit, the unit has to be connected
to the hot water circuit with copper tubes 15/13.
NOTE! A REGULATING VALVE IS INCLUDED IN THE WATER-OPERATED HEATING UNIT.
VALLOX pressure difference switches
If the unit is equipped with pressure difference switches that monitor the pressure
difference in the supply and / or extract air ducts, their correct values have to be
set after the ducts and the related air terminal devices (such as valves and grilles)
have been mounted and adjusted. For further details, see the Instructions for using
VALLOX 252 D.
10
2
Page 11
VALLOX 252 D
Silencer
General
• The silencer is a duct silencer that should be mounted on top of
VALLOX 252 D. The silencer includes a cover that can be
opened, enabling the cleaning of the silencer without
detaching the ducts.
• The silencer unit also features detachable silencer segments in
supply and extract air ducts.
• 4 ø250 external fittings enable the laying of ducts straight
from the unit by using bends etc.
• The top of the silencer unit incorporates lead-in sealings for the
lead-through tubes of cables and for the supply and return
water pipes of a water heating unit, if one is used.
• The weight of the silencer unit is 105kg including the door,
and 82kg without the door.
MOUNTING INSTRUCTIONS
Mounting
NOTE! BEFORE MOUNTING, CHECK THE MODEL OF VALLOX 252 (L or R).
• Detach the door of the silencer. (See the adjoining picture.)
• Detach the cable sleeves equipped with draught limiters (see the figure, item D).
• Cut through the lead-in sealings for the cable sleeves at the bottom of the
exhaust duct of the silencer unit (no isolation inside). NOTE! VALLOX 252
model L or R. (See the figure.)
• If VALLOX 252 is equipped with a water heating unit,
also detach the silencer segment located in the supply
air duct of the unit. NOTE! VALLOX 252 model L or R.
(See the figure.)
• Lift the silencer unit on top of VALLOX 252. Make sure
that the cable sleeves go through. (See the figure,
item D.)
• Mount the lead-through cable tubes (included in the
delivery), pushing them through the lead-in sealings
on top of the silencer unit, and screwing them to the
cable sleeves. (See the figure, item C.)
• Lay the cables to be connected through the leadthrough tubes to the connection box inside VALLOX
252.
• If a water heating unit is used, lead the supply and
return pipes (not included in the delivery) of the
heating unit through the lead-in sealings on top of the
silencer unit and VALLOX 252, and connect them to
the supply and return water outlets with a straight
fitting, for instance.
(See the figure, items A and B.)
• Mount the sound silencer segment in place.
• Carefully fix the door of the silencer in place.
• Fix the ducts steadily and tightly to the outlets. If ducts
are to be isolated, do so following the ventilation
plan.
Supply and return
water pipe
ø15/13 2 pcs
Straight fitting
MS15 2 pcs
Supply and return
water outlet 2 pcs
Silencer segment
Lead-through tubes
for cables 3 pcs
Supply and return water pipe
ø15/13 2 pcs
Lead-in sealings for supply
and return water pipes 2 pcs
Silencer unit (Note! model)
Duct fitting ø250 4 pcs
Lead-through tubes for cables 3 pcs
Lead-in sealing for the cable
lead-through tube 3pcs
Lead-in sealing for cable
sleeve 3 pcs (bottom)
VALLOX 250 L (Note!
model)
Cable sleeve equipped with draught-limiter 3 pcs
Cable sleeve 3 pcs
11
Page 12
VALLOX 252 D
MOUNTING OF CONTROL PANELS AND SENSORS
ONLY AN AUTHORIZED PERSON MAY PERFORM
ELECTRICAL CONNECTIONS!
BEFORE CONNECTING THE CABLES, MAKE SURE
THAT THEY HAVE BEEN DISCONNECTED FROM THE
MAINS SUPPLY!
VALLOX 252 D-L
OUTDOOR
AIR TO THE
UNIT
SUPPLY WATER
TO THE RADIATOR
RETURN WATER
FROM THE RADIATOR
Panel address
1
SUPPLY AIR
FROM
THE UNIT
EXTRACT
AIR TO
THE UNIT
ELECTRICAL
CONNECTIONS
• HUMIDITY SENSOR
CONNECTION CABLE
• CONTROL PANEL
SENSOR
• CO
2
• LON CONTROLLER
FEEDER CABLE
DISTRIBUTION PANEL
EXHAUST
AIR GOING OUT
electrical connections
VALLOX electrical connections
• The unit is connected permanently to the distribution network. The connection box
is located inside the unit, next to the exhaust air duct outlet.
• The cables to be connected are led to the unit through the cable glands with
draught-limiters and the cable sleeves located beside the exhaust air duct outlet.
Mounting
• Detach the upper door of the unit (screw M8x70.5 pcs).
• Detach the cover of the connection box (screw 3.5x9.5, 2 pcs).
• Mount and connect the cables needed to the terminal block following the
connection instructions.
• The external wiring diagram is included in these instructions, and it is also found
inside the cover of the connection box.
• The internal wiring diagram is included in these instructions, and it is also found
on the cover of the fuse box inside the unit.
Mounting the control panel
• The control panel comes in a surface-mount box. The control panel can be
mounted on the instrument box or on the wall.
• Connect the control panel as stated in the connection instructions for VALLOX
252 D.
Connection cable type for instance NOMAK 2 x 2 x 0.5mm
Note! If two or more control panels are mounted, they are connected serially, and they have to be
given different addresses.
Control panel mounting, detaching, and wiring
The control panel is wired directly from the VALLOX 252D connection box. The
control panel can also be wired serially with a CO
panel (see the external electrical diagram, page 16).
sensor or another control
2
Control panel addresses
If two or more control panels are connected to the system, the addresses of the
control panels have to be changed. (See Section 1.3.9 in the instructions for use
and maintenance.)
For example 3 control panels.
• Connect the first control panel to the unit and change its address to 3.
• Connect the second control panel to the unit and change its address to 2.
• Connect the third control panel and check to see if its address is 1.
If control panels have the same address, they go to bus fault state. In this case, remove one of the
control panels and change the address of the other panel. The above mentioned situation can arise in
connection with the later installation of an additional control panel.
2
+0.5mm2.
Surface mounting of a controlpanel
A control panel is mounted on
the wall or on a 1-part
instrument box.
Width 90 mm
Height110 mm
Depth23 mm
Wiring
1 2 3 4 5
+ – A B M
Control panel electronics board
12
2
Cable:
NOMAK 2 x 2 x 0.5 mm
2
+ 0.5 mm
NOTE!
Faulty coupling of the (+) wire destroys
the control panel!
1 = orange 1 = +
2 = white 1 = –
3 = orange 2= A
4 = white 2= B
5 = metal=
ca. 21 VDC
}
signal ground
2
Page 13
VALLOX 252 D
MOUNTING OF CONTROL PANELS AND SENSORS
Mounting and wiring of the carbon dioxide sensor
The CO2 sensor is wired directly from the VALLOX 252D connection box, or it can
be wired serially with another CO
electrical diagram on page 9).
Carbon dioxide sensors
• Connect the carbon dioxide sensors one by one.
• When the first carbon dioxide sensor has been connected to the system, switch on
voltage. At this stage, the ventilation unit gives the sensor an address. Repeat the same
procedure for the other carbon dioxide sensors.
sensor or the control panel (see the external
2
Surface mounting
1 2 3 4 5
+ – A B M
14
38
125
76
Carbon dioxide sensor
Wiring
Cable:
2
NOMAK 2 x 2 x 0.5 mm
NOTE!
Faulty coupling of the (+) wire
destroys the carbon dioxide sensor!
1 = orange 1 = +
2 = white 1 = –
3 = orange 2= A
4 = white 2= B
5 = metal= signal ground
+ 0.5 mm
cirka 21 VDC
}
2
CO2 sensor bottom panelCO2 sensor electronics board
13
Page 14
VALLOX 252 D
MOUNTING OF CONTROL PANELS AND SENSORS
Mounting and wiring of the humidity sensor
The sensor is wired directly from the VALLOX 252D connection box.
Humidity sensors
• Connect any humidity sensors to the terminal board in the connection box by connecting the first RH sensor in %RH1, in place of the 6K8 resistor (remove the resistor in this
case), and the second RH sensor in %RH2. See the electrical diagram.
Sensor
bottom
panel
Surface mounting
14
38
125
76
%RH electronics
board
Cable: 2 x 0.5 mm
Wiring
S +
2
14
2
Page 15
VALLOX 252 D
INTERNAL ELECTRICAL CONNECTIONS
VALLOX 252 D - Internal wiring diagram
TE 4 (EXTRACT AIR)
FAN CONTROL WITH VOLTAGE /
CURRENT SIGNALS
USING JUMPER IN VOLTAGE SIGNAL
CONTROL (FACTORY SETTING)
USING JUMPER IN CURRENT
SIGNAL CONTROL
TE 3 (OUTDOOR AIR)
TE 2 (SUPPLY AIR)
TE 1 (EXHAUST AIR)
HEAT RECOVERY CELL
MOTHERBOARD
FAULT SIGNAL
FAULT
FAULT
FIREPLACE
FIREPLACE SWITCH
REMOTE MONITORING S
REMOTE MONITORING GND
REM
FERN
TF = Supply air fan 2x230W
PF = Extract air fan 2x230W
TR= Transformer 230V 4A/24V 25VA
C= Capacitor 6µF
H1= Interference suppressor motherboard
H2= Interference suppressor motherboard
FG= Damper motor 24V
TE= Temperature sensors
R3= Auxiliary resistor 4.7kOhm
R4= Auxiliary resistor 6.8kOhm
15
S= Service switch (Door switch)
LP1= Electric heating unit 2,500W (preheater, option)
LP2= Electric heating unit 2,500W (post-heater, option)
SV= Regulating valve (water radiator, option)
TZ1= Overheating protector +60˚C
TZ2= Overheating protector +95˚C (manual reset)
PDS1 = Pressure difference switch for supply air ducts (option)
PDS2 = Pressure difference switch for extract air ducts (option)
F1= 2A fuse for supply air fans
F2= 2A fuse for extract air fans
F3= 800mA fuse for motherboard
Page 16
VALLOX 252 D
EXTERNAL ELECTRICAL CONNECTIONS
Current signal: 0...20mA
Moving jumpers in the motherboard,
see the internal wiring diagram
REMOTE MONITORIN
(Additional control option)
G
BOOSTER SWITCH
FAULT SIGNAL
PDS S
PDS +
FAULT
FAULT
BOOSTER
REMOTE S
REMOTE GND
REMOTE MONITORING
REMOTE MONITORING
S
% RH-2/+
% RH-2/S
% RH-1/+
% RH-1/S
M
B
GND
VALLOX 252 D
A
+
L1
L
N
-
FAN CONTROL
Voltage signal: 0...10 VDC
S
GND
FAULT SIGNAL
(1A, 24 VDC)
4 X 0.5
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
2x0.5
BOOSTER SWITCH /
FIREPLACE SWITCH
(Additional control option)
REMOVE THE RESISTOR WHEN MOUNTING
THE FIRST HUMIDITY SENSOR IN THE UNIT.
R= 6K8
NOTE! When the VALLOX 252 D unit is equipped with a PREHEATER and
an ELECTRIC POST-HEATING UNIT, a separate 16A power supply is
needed for PREHEATING.
NOMAK 2x2x0,5+0,5
CO
POSSIBLY MORE THAN ONE
OPTION
2
SENSOR
CONTROL PANEL 1
POSSIBLY MORE THAN ONE
1 INCLUDED AS STANDARD
NOTE! When the VALLOX 252 D unit is equipped with a PREHEATER and
a POST-HEATING UNIT WITH WATER CIRCULATION, the L1 and L on the
terminal block are connected.
In this case, THE PREHEATER DOES NOT NEED a separate power supply.