Vent-Axia PureAir Home Assembly instructions

PLEASE READ INSTRUCTIONS IN CONJUNCTION WITH THE ILLUSTRATIONS.
PLEASE SAVE THESE INSTRUCTIONS
Lo-Carbon
PureAir Home
Positive Input Ventilation
Unit
Stock Ref. N°
479090 –PureAir Home
479091 –PureAir Home with Heater
479092 –PureAir Home FD
Installation and Wiring Instructions
220-240V~50Hz

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Installation and Wiring Instructions for the
Lo-Carbon PureAir Home Positive Ventilation Unit.
SAFETY AND GUIDANCE NOTES
IMPORTANT:
READ THESE INSTRUCTIONS BEFORE COMMENCING THE INSTALLATION
1. DO NOT install this product in areas where the following may be present or occur:
1.1. Excessive oil or a grease laden atmosphere.
1.2. Corrosive or flammable gases, liquids or vapours.
1.3. Ambient temperatures higher than 40°C or less than -5°C.
1.4. Possible obstructions which would hinder access or removal of the Fan.
1.5. Relative humidity above 90%
1.6. Sudden ductwork bends or transformations close to the Unit.
2. 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.
3. The fan must be provided with a 3A fused, isolator switch capable of disconnecting
all poles, having a contact separation of at least 3mm.
4. Ensure that the mains supply (voltage, frequency, and phase) complies with the fan’s
rating label.
5. The fan should not be used where it is liable to be subjected to direct water spray.
6. This appliance can be used by children aged from 8 years and above and persons
with reduced physical, sensory or mental capabilities or lack of experience and
knowledge if they have been given supervision or instruction concerning use of the
appliance in a safe way and understand the hazards involved. Children shall not play
with the appliance. Cleaning and user maintenance shall not be made by children
without supervision.
7. Precautions must be taken to avoid the back-flow of gases into the room from the
open flue of gas or other fuel-burning appliances.
8. Children of less than 3 years should be kept away unless continuously supervised.
9. Children aged from 3 to 8 years shall only switch on/off the appliance provided the
unit is installed as intended for normal operation and they have been given
supervision or instruction concerning safe use of the appliance and understand the
hazards involved.
10. Children aged 3 to 8 shall not plug in, regulate and clean the appliance or perform
user maintenance
Caution - some parts of this product can become very hot and cause burns.
Particular attention has to be given where children and vulnerable people are
present.
A. INTRODUCTORY NOTES
The Vent Axia Lo-Carbon PureAir Home is a positive input ventilation unit, designed to be installed in the loft of a
dwelling to continually supply filtered fresh air into the building.
The system consists of a fan unit, an optional heater unit and a diffuser with a short length of flexible ducting.
The Lo-Carbon PureAir Home has two fully adjustable speed settings; ‘Trickle’ and ‘Energy Recovery’. These
speeds are set during installation; there are 5 pre-set speeds or an option allowing the speeds to be chosen
manually from 10L/s to 60L/s.

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The Lo-Carbon PureAir Home uses a sensor to monitor the temperature in the loft, automatically adjusting the air
volume when necessary.
‘Trickle’ speed is automatically selected when the ambient loft temperature is less than 18°C.
‘Energy Recovery’ is automatically selected when the ambient loft temperature is between 18 and 27°C.
If the ambient loft temperature exceeds 27°C, the Lo-Carbon PureAir Home will automatically switch to standby (no
airflow).
For the model supplied with a heater units (479091 & 479092), the element is activated by default when the loft air
temperature is below 10°C; the system will then work to maintain an input air temperature of 10°C. This temperature
threshold can be adjusted between 5°C and 20°C during commissioning.
The heater unit can be installed either to the fan unit or directly to the diffuser spigot.
Please note: You cannot fit the heater unit to the diffuser on “FD”models.
B. INSTALLATION
TYPICAL INSTALLATION
Lo-Carbon PureAir Home UNIT:
Prior to installation ensure that the loft is adequately ventilated. The following tips can be used as a basis for this.
However this is not an exhaustive list.
Ensure that any ridge vents, tile vents and continuous air gaps are not blocked. These may not be present in older
properties; however there should be enough ‘leakage’ to accommodate the requirements of the Lo-Carbon PureAir
Home unit.
One method of checking this is by entering the loft, closing the loft hatch, switching off the lights and looking for any
daylight penetration. If daylight is visible it is reasonable to assume that there is adequate ventilation within the loft.
There may well be occasions where a loft is so well sealed that additional ventilation may need to be provided by the
owner/occupier. This will not only assist the operation of the Lo-Carbon PureAir Home, but may also help to prevent
future expensive structural damage caused by inadequate air movement. It should be noted that there can never be
too much ventilation in a loft.
Ensure that all water tanks are covered and sealed.
Check that all water pipes are lagged.
Ensure that any extract fans are discharging to the outside and not into the loft.
Check that the loft hatch is tightly sealed.
Ensure that all holes in the ceilings are sealed, i.e. ceiling light fittings etc.
A visual inspection of any flues or chimneys for leakage in the loft should be carried out by the installer.
If any leakage points are found, or if there is any doubt at all, the installer should advise the house owner/provider as
soon as possible and seek instruction from them before proceeding with the installation.
Fig.1.

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Flexible ducting is supplied as standard. Ensure that this is pulled out and does not allow any moisture to collect; it
should be a smooth single curve to the grille. If the application requires a fixed 90 degree bend, straight ducting may
be used. See Spares and Accessories on page 11.
C. Hanging method:
The Lo-Carbon PureAir Home can be hung from a roof beam (Fig. 2). Fix the screw eye to a convenient roof beam.
Use the cord provided to loop through the eye and around the handle on the unit, there are various notches for the
cord to run through, tie the two ends together using a suitable knot such as an over hand or fisherman’s knot.
Ensure that the route for the flexible ducting has gentle bends and that the duct cannot be crushed.
Fit the filters to the unit. Please make sure that the filters are fitted correctly. This will ensure that all the fresh
air entering the dwelling has passed through the filter first.
Ensure that the screw eye is attached to the beam strongly enough and that the beam is in sufficient
condition to withstand the load. The unit weight is approximately 4 kg.
D. Floor mounting:
Attach the mounting legs to the unit, two per side.
Find a suitable location to fix the unit near to where the diffuser is to be located. Ensure that the route for the flexible
ducting has gentle bends and that the duct cannot be crushed Fig.3.
The legs and feet can be adjusted to suit ceiling joists of varying spans. Adjust the legs and feet so that the unit
spans over two joists. Secure the feet to the joists with screws, Fig.4. In the unlikely event that the legs cannot span
the ceiling joists affix the unit to a wooden board or two lengths of timber which can then be screwed to the joists.
Fit the filters to the unit. Please make sure that the filters are fitted correctly. This will ensure that all the fresh
air entering the dwelling has passed through the filter first.
Fig. 4.
Fig.2.
Fig. 3.
Fig.2.
Filters
(See pg. 8)

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400-600mm Joist Dimensions with Unit Clearance Heights
E. DIFFUSER GRILLE:
IMPORTANT: PureAir Home FD models are provided with a different diffuser.
Please note: You cannot fit the heater unit to the diffuser on “FD”models.
The diffuser must be carefully sited to ensure the maximum effectiveness of the system. It should be fitted in the
ceiling of a common area, ideally above the landing so that the incoming air can reach all the rooms.
Cut the flexible ducting to a suitable length, where possible stretch the ducting to its maximum extent and ensure that
there is one continuous smooth bend to the diffuser. The ducting must remain a minimum of 1m in length.
Remove the loft insulation from the location of the diffuser and cut a 240-260mm dia hole in the ceiling.
Ensure the four locking tabs are folded in and then push the spigot in to the hole. Holding the diffuser in place; screw
the four screws until the locking tabs are holding the diffuser tight against the ceiling (Fig.5). It is important not to
over tighten these screws as this may warp the diffuser.
Fit the free end of the flexible ducting to the diffuser spigot using the worm drive clip supplied.
The diffuser should not be situated within 1m of a smoke detector, however if this is not possible the Lo-
Carbon PureAir Home has provisions to blank off the airflow for up to two quadrants of the diffuser. Two
blanking plates are provided; these should be pushed on to the support struts inside the diffuser as
required. This should be done before the diffuser is installed in the ceiling as when the screws are tightened
down the plates can no longer be removed. See Fig.6, showing blocking off opposing quadrants, note any 1
or pair of quadrants can be blocked off as necessary for the install. These block off plates can also be used
to ensure the supply air is spread across a room rather than directed at close by walls.
Blanking off one side reduces the flow by about 6%, but blanking off two sides reduces the flow by about 20% and so
if two sides are blanked off then you should consider increasing the fan speed to maintain the appropriate airflow.
Fig. 5.
Fig. 6.

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IMPORTANT
(Read only if installing with PIV
twin spigot kit Ref:- 449071)
Ensure that the adjustable diffuser supplied
with the kit is installed nearer to the PureAir
Home unit than the round diffuser supplied
with the unit. This allows both flows to be
balanced.
Not to be used with FD models unless the
diffuser supplied with the kit is replaced
with diffuser part 475664
F. Heater Unit
The heater unit must not be located directly below a socket.
Please note: You cannot fit the heater unit to the diffuser on “FD” models.
The heater unit can be mounted either to the unit or to the diffuser spigot see Fig. 7, where fitted to the unit there are
locating pins that fix the heater to the unit using a bayonet fitting and the locking screw. When fitted at the diffuser
end, make sure the direction of the heater is facing the correct way, arrow label on heater must point towards
diffuser. The power and sensor cables must be plugged in to the front of the fan unit see Fig 8.
PURE AIR
HOME UNIT
Y- PIECE SUPPLIED WITH
PIV TWIN SPIGOT KIT 449071
ROUND DIFFUSER SUPPLIED WITH
PIV TWIN SPIGOT KIT 449071.
(INSTALL NEAR UNIT)
ROUND DIFFUSER AS ABOVE
(SUPPLIED WITH PURE AIR HOME UNIT)
Fig. 8.
Fig. 7.
Unit Mounted
Apply worm drive clips provided
in positions shown
Apply worm drive clips provided
in positions shown
Apply suitable duct tape to seal
between heater and diffuser.
Diffuser Mounted

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G. WIRING
A means for disconnection must be incorporated, in the fixed wiring in accordance with the wiring
regulations.
WARNING: THE POSITIVE VENTILATION UNIT AND ANCILLARY CONTROL EQUIPMENT
MUST BE ISOLATED FROM THE POWER SUPPLY DURING THE INSTALLATION / OR
MAINTENANCE.
Mains supply voltages (220-240V ac) are present in this equipment which may cause death or serious injury by
electric shock. Only a qualified electrician or installer should connect the power supply to this unit.
The Lo-Carbon PureAir Home is designed for operation from a single-phase alternating current source (220-
240V AC).
A 2 m integral mains flying lead is connected to the unit for connection to a 3A switched fused spur. It should be
capable of disconnecting all poles, having a contact separation of at least 3mm.
PureAir Home & PureAir Home with Heater unit:
Ensure the local AC power supply is isolated.
The product has a pre-wired flying lead. Connect the brown core to Live and the blue core to Neutral.
Use cable clamps and clips to secure the cable, as appropriate.
Fig.9
IMPORTANT:
PureAir Home FD models must be
installed with a smoke alarm with a relay
to ensure compliance with building
regulations.
In order to have the product switch off in the
event of a fire it must be wired using a smoke
alarm with a relay system.
Use Fig.9 as a reference and refer to the
instructions provided by the manufacturer
of the smoke alarm and relay in order to
wire the unit correctly. Ensure the relay
works correctly by testing the fire alarm;
the unit should switch off when the alarm
is sounding.
FOR REFERENCE ONLY
PureAir
Home Unit

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H. START UP SEQUENCE
When the unit is switched on it will first run through a period of system checks. During this time the display will show
various system parameters before the fan motor starts. After 10 seconds the product will be ready for
commissioning.
I. COMMISSIONING
Accessing the Commissioning Menu (See page 10 for Commissioning Menu Structure)
If the fan is powered and the display is not lit then press any button to access the menu. After 30 seconds without
menu activity the display will switch off, any changes to the settings will then be applied.
There are three buttons on the front of the unit:
The + button is used to increase the value of a setting, the –button is used to reduce the value of a setting and the
Mode button moves to the next menu item.
J. Lock feature
If the lock feature is enabled; when a button is pressed the display will show, –––. At this point enter the
three digit code by first pressing + or –until the first digit is correct then press MODE to move to the next
digit. Repeat until the code is entered and press MODE to enter the commissioning menu. If the code is
entered incorrectly, wait until the screen switches off then press any button to begin again.
K. AIR FILTER
Fitting the foam seals (x6) to spigot ends before fixing the filters.
+
-
MODE

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Line up the foam seals with the edge of the spigots, making sure not to cover spigot clips as shown.
Then fit filters over foam, on to the spigot ends.
The Lo-Carbon PureAir Home is provided with G4 filters which are suitable for removing airborne contaminants such
as pollen and dust.
Where improved filtration is required optional F7 filters can be used. These filters are effective at removing finer
particles such as particulate emissions from diesel engines. In urban areas close to main roads F7 filters are
advisable in order to ensure the supply air is clear of these particles which are potentially harmful to health.
Where F7 filters are fitted, please ensure the flow rate of the fan is as expected. F7 filters cause extra system
resistance so it may be necessary to increase the fan speed to compensate.