Vent-Axia SELV TP, 404878, SELV HTP, 404879 Installation Instructions

Stock Ref. N°

PLEASE READ INSTRUCTIONS IN CONJUNCTION WITH ILLUSTRATIONS.

FAN UNIT 12V DC

SELV (CLASS III)

Response
SELV

CONTINUOUS EXTRACT FAN

Installation and Wiring Instructions

CONTROLLER 220-240V 50Hz MAINS SUPPLY (CLASS II)
WITH 12V DC SELV OUTPUT

PLEASE SAVE THESE INSTRUCTIONS.

Response
SELV TP 404878

Response
SELV HTP 404879

IPX7

Installation and Wiring Instructions for the Response SELV Range of Extractor
Fans.

IMPORTANT:
READ THESE INSTRUCTIONS BEFORE COMMENCING THE
INSTALLATION

DO NOT install this product in areas where the following may be present or occur:

• Excessive oil or a grease laden atmosphere.

• Corrosive or flammable gases, liquids or vapours.

• Ambient temperatures higher than 40°C or less than –5°C.

• Possible obstructions which would hinder the access or removal of the Fan.

SAFETY AND GUIDANCE NOTES
A.

All wiring to be in accordance with the current I.E.E. Regulations,
or the appropriate standards of your country and

MUST

be

installed by a suitably qualified person.

B.

The Fan should be provided with a local isolator switch capable
of disconnecting all poles, having a contact separation of at least
3mm.

C.

Ensure that the mains supply (Voltage, Frequency, and Phase)
complies with the rating label.

D.

The Fan should only be used in conjunction with the appropriate
Vent-Axia products.

E.

The fan should only be used in conjunction with fixed wiring.

F.

When the Fan is used to remove air from a room containing a
fuel-burning appliance, ensure that the air replacement is
adequate for both the fan and the fuel-burning appliance.

G.

The Fan should not be used where it is liable to be subject to

direct water spray for prolonged periods of time.

H.

Where ducted Fans are used to handle moisture-laden air, a
condensation trap should be fitted. Horizontal ducts should be
arranged to slope slightly downwards away from the Fan.

I.

This appliance is not intended for use by persons (including

children) with reduced physical, sensory or mental capabilities, or
lack of experience and knowledge, unless they have been given
supervision or instruction concerning use of the appliance by a
person responsible for their safety.

2

J.

Young children should be supervised to ensure that they do not

play with the appliance.

DESCRIPTION

The Response SELV fan is a continuously running extract fan for kitchens, utility rooms,
bathrooms and toilets. The electrical supply to this fan is 12V DC SELV from the mains
controller. This means that the fan may be installed within reach of a person using a fixed bath
or shower, i.e. in a nearby wall. However, for reliable operation, the fan must not be placed
where it could be submerged in water or regularly exposed to direct water spray, e.g. from a
shower head whether permanently fixed or movable.

The product incorporates an airflow detection system that detects the installation duct
resistance and maintains the correct fan speed to achieve the preset extract flow rate of either
6l/s, 8l/s or 13l/s, minimising energy use and noise (see Section C-Setup for more information).

The incorporated LED display allows the installer to verify the installed flow rate, and also
provides feedback for system pressure and days installed (for landlords).

The fan can be wall, panel/ceiling or window mounted.

ACCESSORIES (not supplied)
WALL FITTING KIT

A range of white (stock ref. 254102) or brown (stock ref. 254100) 100mm wall kits are available
for installing into most walls using telescopic liners supplied.

WINDOW KIT stock ref. 407927
CEILING KIT stock ref. 407928
150mm COVERSION KIT stock ref. 408680

A. INSTALLATION

SITING THE CONTROLLER

1. The controller must not be installed in a shower cubicle or enclosure. It must be sited
away from direct sources of water spray and out of reach (1.5m) of a person using a fixed
bath or shower.

2. Site away from direct sources of heat. Ambient temperature range 0 to 40ºC. Do not site
in an area containing excessive levels of grease.

3. Decide where to site the controller and fan and work out the required cable runs.

PANEL/CEILING MOUNTING

1. Cut a 105mm diameter hole.

2. Remove the front panel by carefully pulling away from the fan.

3. Loosen the two self-retaining screws and remove the inner grille by carefully pulling away
from the housing.

4. Mark the screw centres through the holes in the fan back plate. Drill, plug and screw into
position. Attach ducting as required for the installation.

5. Wire the fan as described in Section B-Wiring. Adjust any settings as required (see
Section C-Setup).

6. After installation, ensure impeller rotates freely.

7. Replace the inner grille and tighten the retaining screws. Replace the front panel.

3

WALL MOUNTING

1. For wall mounting cut a 117mm diameter hole through the wall and insert the wall sleeve.
Slope the sleeve slightly downwards away from the fan. Where necessary cut to length
and cement both ends into position flush with the wall faces.

2. Fix exterior grille into position with the louvres positioned downwards.

3. Remove the front panel by carefully pulling away from the fan.

4. Loosen the two self-retaining screws and remove the inner grille by carefully pulling away
from the housing.

5. Mark the screw centres through the holes in the fan back plate. Drill, plug and screw into
position.

6. Wire the fan as described in Section B-Wiring. Adjust any settings as required (see
Section C-Setup).

7. After installation, ensure impeller rotates freely.

8. Replace the inner grille and tighten the retaining screws. Replace the front panel.

WINDOW MOUNTING

1. Refer to window kit instructions supplied with the kit.

B. WIRING.

WARNING: THE FAN AND ANCILLARY CONTROL EQUIPMENT MUST BE
ISOLATED FROM THE POWER SUPPLY DURING THE INSTALLATION / OR
MAINTENANCE.

IMPORTANT

• The Controller MUST be surface mounted to allow air to freely circulate around the unit.
When installed in a loft void it MUST NOT be enclosed or covered with insulation.

• The cross - sectional area of supply cord used should be ranged from 1 -1.5mm2.

1. Select and follow the appropriate wiring diagram. (Fig. 1, 2 or 3)

2. Check all connections have been made correctly and ensure all terminal connections and
supply wires are securely fastened.

3. Ensure the impeller rotates and is free from obstructions.

C. SETUP

WARNING: THE FAN AND ANCILLARY CONTROL EQUIPMENT MUST BE
ISOLATED FROM THE POWER SUPPLY DURING THE INSTALLATION / OR
MAINTENANCE.

1) Trickle speed selection (6l/s or 8l/s) – (Fig. 5) (TP & HTP models)

In normal running mode the fan can extract at either 6l/s (22m3/h) or 8l/s (29m3/h) flow rate.
The fan will boost to 13l/s (46.8m3/h) when the LS connection is switched or humidity rises
above the set point (see humidity setting below).

• Factory set at 6l/s (22m3/h).

• Remove jumper connector (JP1) if 8l/s (29m3/h) extract flow rate is required.

2) Airflow detection system – enable/disable (Fig. 5) (TP & HTP models)
The airflow detection system will detect the installation duct resistance and also react to
external wind conditions to ensure the fan maintains a constant extraction rate. This can
cause the fan to ramp up and down and in most applications will not be required. To turn this
feature on, complete the following:

• Push dip switch 1 (SW1) into the on position to turn on constant flow mode.

4

• Push dip switch 1 (SW1) into the off position to turn off constant flow mode.
(Factory set)

IMPORTANT – On first power up, the fan will run through its initialisation routine. For the first
15 minutes, the flow rate, pressure and day logger will be displayed. The fan may not be fully
functional until this is over. After the first 15 minutes, the fan will calibrate. See Fig.7 for the
calibration procedure. Once this is complete the fan will operate normally with the display off.

3) LED Display with prism (Fig. 6) (TP & HTP models)

For the first 15 minutes EVERY time the fan is powered off and on (via the isolator), the
display will cycle between displaying the actual airflow rate (l/s) being achieved* and system
pressure (Pa). They will cycle every 10-20 seconds, where the pressure will flash, and the
airflow rate will be on constantly. The day logger feature will only be displayed once, after
the first cycle of displaying the flow rate and system pressure.

*Airflow detection system must be enabled to display the calibrated flow rate.

4) Adjustable timer (TP model only)

The TP model incorporates an adjustable overrun timer. This adjusts the time the fan will
continue to run on boost after the LS connection has been deactivated. The timer function is
factory set at approx 15 minutes but can be adjusted between 1 & 30 minutes. This is also
the run time period for the integral pullcord.

• To REDUCE the operating time, use a small screwdriver to turn the adjuster Fig.5.
CLOCKWISE. To a minimum setting of 1 minute.

• To INCREASE the operating time, use a small screwdriver to turn the adjuster Fig.5.
ANTI-CLOCKWISE. To a maximum setting of 30 minutes.

5) Fixed timer (HTP model only)

The HTP model incorporates an optional fixed timer – set at 15 minutes. This is the time
the fan will continue to run on boost after the LS connection has been deactivated. The
integral pullcord timer is fixed at 15 minutes and cannot be disabled.

• To ENABLE the fixed overrun timer, link JP2 as shown in fig. 5.

• To DISABLE the fixed overrun timer, remove the link in fig. 5.

6) Adjustable ambient response humidistat (HTP model only)

The HTP model incorporates an adjustable ambient response humidistat. The fan will
increase the extract rate if the humidity rises above the set point – adjustable via the pot
shown in fig. 5.

• To LOWER the set-point use a small screwdriver to turn the adjuster Fig.5.
CLOCKWISE. This makes the controller MORE sensitive.

• To RAISE the set-point use a small screwdriver to turn the adjuster Fig.5.
ANTICLOCKWISE. This makes the controller LESS sensitive.

 Note: The ambient response feature will automatically boost the fan to 13l/s if the

humidity rises quickly irrespective of the set point and run on for the pre-determined
timeout period.

7) Pullcord

The integral pullcord activates the timer (see 4 and 5 above) and the fan will run at 13l/s
for the set time period. If the pullcord is pulled for a second time (once activated), the
timer will be cancelled and the fan will revert back to the trickle extract rate.

5

 To remove the pullcord, cut the cord and leave the switch in place. There is no need

to switch the fan on/off beforehand.

8) System pressure detection (TP & HTP models)

The fan can detect the system pressure for fault finding. If the fan seems noisy or cannot
achieve the desired flow rate, this could be due to a blocked duct or the ducting has not
been suitably stretched during installation (if flexible ducting is used). This is displayed
during the first 15 minutes EVERY time the fan is powered off and on (via the isolator).
The number is displayed in Pascals (Pa) and the higher the number, the more torturous
the system (and air path) – i.e. harder for the fan to move the air through the ducting. As
a consequence the fan has to use more energy and it will increase the fans noise level.

The fan will maintain the correct airflow rate up to a maximum of 30Pa system pressure.
The system pressure will be different for all speeds, but highest on the 13l/s setting.

9) Fan silent running boost mode: This feature delays the boost operation for a maximum
of 20 minutes to reduce noise and cold drafts while bathing. After LS is disconnected,
the fan will look at the amount of time since the LS was activated and then run the fan on
boost for that same period or to a maximum of 20 minutes, whichever is shorter.

a. Dip switch 2 in the off position – Traditional mode (factory set) (fig. 5):

i. Standard running - with LS off, pullcord off. Fan continues to run on the set

trickle speed - 6 or 8l/s.

ii. When the integral pullcord is activated (TP & HTP model only), the fan will

run at 13l/s (boost) for a timed period.(Timer is adjustable on TP model,
but fixed to 15 minutes on the HTP model).

iii. When the LS is connected, the fan will run at 13l/s until deactivated (plus

overrun timed period where applicable).

b. Dip switch 2 in the on position:

i. Standard running – with the LS off, pullcord off. Fan continues to run on the

set trickle speed - 6 or 8l/s.

ii. When the integral pullcord is activated (TP & HTP model only), the fan will

boost as per “Traditional Mode” above.

iii. When the LS is activated, the fan will remain in trickle mode until the LS is

disconnected for a maximum of 20 minutes.

iv. After this 20 minute period or when the LS is disconnected (whichever

happens first), the fan will change to 13l/s (boost mode) and continue to run
on boost for the same period as between the LS activation and
deactivation, up to a maximum of 20 minutes.

v. However, if the LS is deactivated within 3 minutes of activation, then the

fan continues in trickle mode and does not boost.

10) Calibration

The airflow sensor is calibrated at the factory using UKAS accredited equipment.
Details of the equipment and certification can be found on the inside of the fan.

D. SERVICING AND MAINTENANCE.

WARNING: THE FAN AND ANCILLARY CONTROL EQUIPMENT MUST BE
ISOLATED FROM THE POWER SUPPLY DURING MAINTENANCE.

6

1. At intervals appropriate to the installation, the fan should be inspected and cleaned to
ensure there is no build-up of dirt or other deposits.

2. Carefully pull the front panel off the inner grille. (fig. 4)

3. Wipe the inlets and front face with a damp cloth until clean. Be careful not to push dirt into

the airflow sensor.

The fan has sealed for life bearings, which do not require lubrication.

E. TROUBLESHOOTING

1. Display shows 999 during calibration.

a. Cause:

i. The fan failed to calibrate due to excessive system pressure

b. Solution:

i. Check that the ducting is not blocked and where flexible ducting is used

that it is stretched as much as possible. Switch the power off and on again
to retry calibration.

2. Fan continuously speeds up and down:

a. Cause:

i. This usually means the fan cannot stabilise at the desired airflow rate.

ii. This could be due to the ducting being blocked, or being very windy.

b. Solution:

i. If this persists after the ducting has been checked or the property is very

exposed to high winds, it is recommended to turn the airflow detection
system off. (Section C2)

3. The fan continuously runs in boost (HTP model only):

a. Cause:

i. The room is damp or recently redecorated.

ii. The humidity set point is set too low.

b. Solution:

i. If the room is damp or has recently been decorated, it could take up to 2

weeks for the humidity levels to stabilise. Please leave the fan to dry out the
room and after this period the fan should run normally.

ii. The humidity set point could be set too low. Adjust the humidity set point to

a higher setting. (Section C6)

4. The fan does not turn to boost when the humidity is high:

a. Cause:

i. The humidity set point is set too high.

b. Solution:

i. Adjust the humidity set point to a lower setting. (Section C6)

5. Water is dripping out of the fan when installed in a ceiling:

a. Cause:

i. This is caused by condensation forming on the inside of the ducting and

dripping out of the fan inlet.

b. Solution:

i. This is normal and the fan is designed to handle condensation build up.

However a condensation trap connected immediately after the fan will help
to prevent water dripping into the room.

7





Pullcord disabled

Siting
the
fan.

Fig.1 Continuous trickle (6l/s or 8l/s) with pullcord boost (13l/s)

1 Phase Supply

(220-240V 50Hz).

L

~

N

FUSE

12V D.C
SELV Supply

Switched

Fused Spur

(3A)

LS

N L

Controller

LS12V

0V

Fig.2 Continuous boost (13l/s)

1 Phase Supply

(220-240V 50Hz).

L

~

N

FUSE

Switched

Fused Spur

(3A)

LS

LINK

N

L

Controller

12V D.C

SELV Supply

12V

LS

0V

Fig.3 Continuous trickle with boost facility via LS or internal pullcord

~ N

12V D.C

SELV Supply

LS

N L

LS12V

Controller

0V

LS

N

L

LS

NL2

3

2

1

LS

3

1

NL2

Fan

Fan

3

1

Fan

8

1

2

O

N

2

O

N

O

N

Fig.4. Removing the grille for wiring and setting the controls

Pull front panel as shown. Loosen screws – DO NOT REMOVE FROM GRILLE
(the screws are self-retaining)

Pull inner grille away from housing as shown. When replacing grille, ensure the flow sensor is

Fig.5. Controls

Note:- Before changing any of the dipswitch positions the fan
must be isolated from the power supply.

Trickle speed (JP1) (All models)
8l/s = Remove Jumper Connector
6l/s = Replace Jumper Connector (factory set)
(For 13l/s, permanently link terminal connections L to LS)

Airflow detection system (All models)
Auto sensing mode = Dip switch 1 (SW1) into the

on position to turn on airflow detection system.

Manual mode = Dip switch 1 (SW1) into the off
position to turn off airflow detection system

Silent running boost mode
Off = Dip switch 2 (SW1) in the off position

Traditional mode (factory set)

On = Dip switch 2 (SW1) in the on position
This feature will delay the boost operation
for a maximum of 20 minutes.
(see C.SETUP section Item 9)

(TP & HTP only)

aligned with the corresponding slot in the grille.

1

JP2 - (HTP
ONLY)
Fixed timer

Adjuster for
timer (TP) or
humidistat
(HTP)

1

2

O

N

1

2

JP1 - Trickle
speed

enable/
disable
jumper

SW1 – Airflow
detection system
and Silent running
boost

9

Pressure will be displayed like this:

17

(flashing

–

17Pa system pressure

)

Fig. 6. Display and prism

The display can only be seen from the side. This is to allow the installer to view the display with the cover
attached as this can affect the airflow through the sensor.

Every 10-20 seconds the display will switch between displaying airflow rate and system pressure. The system
pressure will flash.

Airflow will be displayed like this: 13.2 (13.2l/s flow rate)

Fig.7 Calibration Process

After 15 minutes of run time, from initial start up the fan will enter the calibration process. This process will
take a few minutes during which time the fan will speed up and down a number of times. This allows the flow
sensor to calibrate the fan for the installation.

Important: The fan will fail to calibrate unless it is installed in a duct or window kit. Do NOT

attempt to calibrate before the unit is installed.

To bypass the 15 minute wait for calibration to start, pull the pull cord for at least 6
seconds then release it.

is displayed when calibrating 13l/s

is displayed when calibrating 8l/s

is displayed when calibrating 6l/s

is displayed on calibration completion

is displayed If calibration fails, power
cycle the fan in order to retry calibration.

To reset calibration put dip switch 1 (SW1) into the off position, turn the fan on and allow it to run for 30
seconds. Turn the fan off and place dip switch 1 (SW1) to the on position. When the fan is switched back
on it will run the start-up procedure and calibrate itself after 15 minutes of running.

Applicable only to products installed and used in the United Kingdom. For details of guarantee outside the United Kingdom contact your local

Vent-Axia guarantees its products for two years from date of purchase against faulty material or workmanship. In the event of any part being found

that it is adequately packed and accom panied by a letter clearly marked “Guarantee Claim” stating the nature of the fault and providing evidence of

to be defective, the product will be repaired, or at the Company’s option replaced, without charge, provided that the product:-

• Has been installed and used in accordance with the instructions given with each unit.

• Has not been connected to an unsuitable electricity supply. (The correct electricity supply voltage is shown on the product rating label

attached to the unit).

• Has not been subjected to misuse, neglect or damage.

• Has not been modified or repaired by any person not authorised by the company.

Please return the complete product, carriage paid to your original supplier or nearest Vent-Axia Centre, by post or personal visit. Please ensure

The guarantee is offered to you as an extra benefit, and does not affect your legal rights

The Guarantee

supplier.

IF CLAIMING UNDER TERMS OF GUARANTEE

date and source of purchase.

PRODUCT FICHE

exchangers only),

For Residential Ventilation Units (Complying Commission Delegated Regulation (EU) No 1254/2014)

Name: Vent-Axia Vent-Axia

Model ID (Stock Ref.) :

SEC Class C C
SEC Value ('Average') 26.23 26.23
SEC Value ('Warm') 11.86 11.86
SEC Value ('Cold') 51.31 51.31
Label Required? (Yes/No=Out of scope) No No
Declared as: RVU or NRVU/UVU or BVU RVU-UVU RVU-UVU
Speed Drive Multi-Speed Multi-Speed
Type HRS (Recuperative, Regenerative, None) None None
Thermal Eff: [ (%), NA(if none)] N/A N/A
Max. Flow Rate (m3/h) 46.80 46.80
Max. Power Input (W): (@Max.Flow Rate) 1.70 1.70
LWA: Sound Power Level (dB) 50.02 50.02
Ref. Flow Rate (m3/s) 0.01 0.01
Ref. Pressure Diff. (Pa) N/A N/A
SPI [W/(m3/h)] 0.05 0.05
Control Factor & Control Typology: (CTRL/ Typology)
Control Factor; CTRL 0.65 0.65

Control Typology

Declared: -Max Internal & External Leakage Rates(%)
for BVUs or carry over (for regenerative heat

-&Ext. Leakage Rates (%) for Ducted UVUs;
Mixing Rate of Non-Ducted BVUs not intended to be
equipped with one duct connection on either supply or
extract air side;
Position and description of visual filter warning for
RVUs intended for use with filters, including text
pointing out the importance of regular filter changes
for performance and energy efficiency of the unit

For UVUs (Instructions Install Regulated Supply/Extract
Grilles Façade)
Internet Address (for Disassembly Instructions) www.vent-axia.com www.vent-axia.com
Sensitivity p. Variation@+20/-20 Pa: (for Non-Ducted
Vus)
Air Tightness-ID/OD-(m3/h) (for Non-Ducted Vus) N/A N/A
Annual Electricity Consumption: AEC (kWh/a) 0.37 0.37
Annual Heating Saved: AHS (kWh/a)
AHS: Average 26.23 26.23
AHS: Warm 11.86 11.86
AHS: Cold 51.31 51.31

Lo-Carbon Response

SELV TP - 404878

Local Demand

Control

N/A N/A

N/A N/A

N/A N/A

In F&W In F&W

N/A N/A

Lo-Carbon

Response SELV HTP

- 404879

Local Demand

Control

Head Office: Fleming Way, Crawley, West Sussex, RH10 9YX.

UK NATIONAL CALL CENTRE, Newton Road, Crawley, West Sussex, RH10 9JA
SALES ENQUIRIES: Tel: [phone] Fax: [phone]
TECHNICAL SUPPORT: Tel: [phone] Fax: [phone]

For details of the warranty and returns procedure please refer to
RH10 9YX

404896 H 0617

www.vent-axia.com

or write to Vent-Axia Ltd, Fleming Way, Crawley,