Xpelair Natural Air PH 180 User manual

Natural Air
Natural Air PH
Natural Air Plus
180 and 350 Models
Ventilation Unit With Heat Recovery
Installation manual
IMPORTANT:
In this installation manual, especially important notes are marked as
WARNING! or NOTE!

Installation Manual
Contents
Section 1 –Important notes
3
Section 5 –Setting up
27
1.1 Intended use
3
5.1 Requirements for the building
27
1.2 Safety instructions
3
5.2 Requirements for ventilation system
27
Section 2 –Description of the device
4
5.3 Requirements for the technician
27
2.1 Purpose
4
5.4 Setting up procedure
27
2.2 Package contents
4
Section 6 –Control
28
2.3 Operating principle
4
6.1 Display and control panel on the unit
28
2.4 System design
5
6.2 Operating modes
29
2.5 Design
6
6.3 Installer menu
31
Section 3 –Technical data
7
6.3.1 Set Supply and Extract flow rates
31
3.1 Specifications
7
6.3.2 Change Settings
32
3.2 Characteristic curves
8
6.3.3 Load and Save and Reset Parameters
35
3.3 Dimension drawings
9
6.3.4 Diagnostics checks
35
Section 4 –Installation
12
6.3.5 Autocheck Routine
36
4.1 Requirements for the installation
location
12
6.4 Operational functions
36
4.2 Installation of the unit
13
6.4.1 Bypass control
36
4.3 Condensate discharge line
13
6.4.2 Filter monitoring / filter message
37
4.4 Air-duct system
14
6.5 Internal safety functions
37
4.5 Electrical installation
16
6.5.1 Function for safe use with fire safety
37
4.5.1 Installation of Smoke Detector link
wire
16
6.5.2 Frost protection of Heat exchanger
38
4.5.2 Connecting the unit to power supply
17
6.5.3 Frost protection of the property
38
4.5.3 Electronics boards inside the unit
18
6.5.4 Safety cut-out
39
4.5.4 Electrical circuit diagram
20
Section 7 –Fault Finding
40
4.5.5 Installation RH & CO2sensors
(optional)
22
Section 8 –Map of the User menu
41
4.5.6 Installation PIR sensors (optional)
22
Section 9 –Map of the Installer menu
43
4.5.7 Installation air-quality sensor
(optional)
23
Section 10 –Settings Log table
44
4.5.8 Installation smoke detector (optional)
23
10.1 User Settings
44
4.5.9 Installation of duct heaters (optional)
24
10.2 Installer Settings
45
4.5.10 Installation of Ventmiser (optional)
25
Section 11 –Customer Service & Warranty
46
4.5.11 Installation of Ext. filter box
(optional)
26
Section 12 - Environment and Disposal
47
2

Section 1 –Important notes
In this user manual, especially important notes are marked as WARNING! or NOTE!
WARNING:
Warnings against hazards and errors that can cause severe or fatal injuries or can have serious
consequences for the product.
NOTE!
Useful notes and additional information.
This Installation Manual forms part of the ventilation unit and must be kept readily available at all times. For
the installer this manual must be used in conjunction with the User Manual. Both must be handed to any
technicians carrying out work on the unit and must be handed over to the new tenant when moving home.
1.1 Intended use
This ventilation unit is intended exclusively for the ventilation and exhaust ventilation of rooms within a
property. It must be installed in a frost-free interior room only.
Any other use and any use exceeding the design limits is not permitted. Any improper use can damage the
unit and can cause severe hazards.
The unit must not be altered or modified. The unit is guaranteed safe to use in accordance with these
instructions. The instructions in this Installation manual and in the corresponding User manual must be
observed.
1.2 Safety instructions
Failure to observe the safety instructions can cause hazards to the user as well as to the unit and will
invalidate the guarantee.
1.2.1 Installation
The ventilation unit must be installed by a qualified technician in accordance with this Installation manual.
The unit must be installed in a frost-free environment with good access and sufficient space for carrying out
any necessary maintenance or repair work. Two condensate hoses are required and must be correctly taken
to a drain in order to avoid any electrical hazards and any damage to the building. The unit must not be
installed where corrosive or inflammable gases can enter the unit, or where harmful pollutants can affect
people or put people at risk. All applicable fire regulations must be observed and complied with. Connecting
exhaust hoods to the ventilation unit is not permitted.
The unit must be installed by a qualified technician in compliance with all applicable standards and local
regulations, as well as in accordance with the Installation manual.
WARNING:
Before starting any work on the unit, the power supply must be isolated in order to prevent any
electrical hazard.
Install and secure the mains cable through the cover cable gland. Ensure that the bare cable ends are correctly
and tightly secured into the mains supply terminal block.
Any setting up and programming must be carried out by a qualified technician in accordance with the
installation instructions.
1.2.2 Open Flue installations
Using the ventilation unit together with fuel burning devices (e.g. fire places, gas stoves) is subject to
special requirements.
WARNING:
It must be ensured that the unit is correctly set up so that no open flue gases are drawn back into
the room. All applicable national and regional guidelines and regulations must be observed.
3

Section 1 –Important notes / Section 2 –Description of the Device
1.2.3 Start-up, use, interruption
The completed installation must be tested to ensure the unit works correctly. The user must read the User
manual in order to understand the procedures for use and maintenance.
WARNING:
The unit contains rotating fans. Do not put hands or fingers or any other objects into the unit or
ducting as this may cause injuries or damage to the unit.
1.2.4 Maintenance, repair, spare parts
In order to ensure continuous safe operation, the ventilation unit must be maintained regularly. Any
maintenance and repair work other than cleaning or changing filters must be carried out by a qualified
technician. Before opening the unit, turn off all associated circuits and secure against unintentional switching-
on. Use only original spare parts from the manufacturer.
1.2.5 Alterations and modifications
Always consult a qualified technician if any alterations or modifications to the unit or system are required.
Structural changes to the building can also have an effect on the ventilation system: Always consult a qualified
technician.
Section 2 –Description of the Device
2.1 Purpose
The unit is designed for controlled supply and exhaust ventilation of frost-free rooms within a building.
Model 180 Series is used for domestic properties with 1 kitchen and up to 3 additional wet rooms (K + 3).
Model 350 Series is used for domestic properties with 1 kitchen and up to 7 additional wet rooms (K + 7).
(“Wet rooms” include bathrooms, toilets, ensuites, etc).
The air flows through air ducts.
Connecting exhaust hoods to the ventilation system is not permitted. The unit is not to be used as a
dehumidifier.
2.2 Package contents
The unit is delivered with the following package contents:
• Ventilation unit with integrated control panel
• Condensate connection kit
• Installation manual and User manual
2.3 Operating principle
The unit is fitted with two fans using energy-saving “EC” technology which carries out a controlled air
exchange.
Used air is drawn in to the unit as Extracted air from the rooms with the highest air humidity and odour (e.g.
bathroom and kitchen) and is transferred to the outside as Exhaust air via a system of air ducts.
At the same time, a second duct system takes in Fresh air from outside the building and transfers it into living
rooms and bedrooms as Supply air.
Both air flows are completely separate and are passed through a heat exchanger which recovers the waste
heat from the extracted air to warm up the supply air. This ensures that the majority of heat energy is kept in
the building.
An internal bypass can be opened so that fresh air is supplied to the intake rooms without being warmed up
by the heat exchanger. Heat recovery is disabled in this case.
4

Section 2 –Description of the Device
Fig. 2.1 Supply-air/extract-air system with heat recovery
1 Fresh air*
6 Air diffuser
NOTE!
* Outside installation points for the Fresh Air
intake (1) and the Exhaust Air outlet (4) MUST be
sufficiently far enough apart to prevent the
exhaust air being drawn into the property through
the Fresh air duct. (No “re-circulation”).
2 Supply air
7 Air transfer opening
3 Extract air
A Supply-air area
4 Exhaust air*
B Extract-air area
5 Ventilation unit
C Air transfer area
Halls and corridors normally act as transfer areas in which the air from the supply areas flows into the extract
areas. Undercut doors and air transfer grilles are used so that the air flow between rooms is not restricted.
Where fitted, a radial air-duct system with direct pipe routes between air diffusers and supply air/extract air
valves:
• Simplifies the balancing of volume flow rates and pressures
• Prevents sound transmitting from adjacent rooms
• Makes cleaning easier, due to direct pipe routes
2.4 System Design
The ventilation system must be properly designed by a qualified ventilation engineer so that it meets the
requirements of the building.
The plan will determine :
• The location of the Supply air inlets (Low pollution: Usually living rooms, bedrooms, recreation rooms,
offices, etc)
• The location of the Extract air outlets (Higher pollution: Usually bathrooms, toilets, kitchens, utility rooms,
etc)
• The requirement for any undercut doors and air transfer grilles. (Usually Halls and corridors, etc)
• The overall required Supply flow rate
• The overall required Extract flow rate
• Supply and Extract flow rates into individual rooms
(Devices such as grilles or diffuser or dampers can be used to set individual room rates)
5

Section 2 –Description of the Device
NOTE!
See Table 3.1 on Page 7 for Factory set Supply and Extract flow rates.
See Section 6.3 Installer menu –Change the Air flow rates. (As determined by the design).
NOTE!
The following documents are needed for correct designing of the system:
• Details of the building and the rooms or areas to be ventilated.
• Floor plans indicating room use.
• Sectional drawing indicating room heights.
NOTE!
An incorrectly specified system can lead to insufficient ventilation and can cause high noise levels
and an excessive energy consumption.
Applicable guidelines and regulations must be observed and complied with. RXG recommend using:
Domestic Ventilation Compliance Guide and
Approved Document, Part F
Both are available from www.planning portal.gov.uk.
WARNING:
Using the ventilation unit together with open flue fuel burning devices (e.g. fireplaces, gas stoves) is
subject to further special requirements.
Any applicable national as well as regional guidelines and regulations must be observed.
We strongly recommend you consult a qualified specialist.
WARNING:
Fire regulations must be complied with. E.g. Fire dampers should be fitted, where required.
2.5 Design
Fig. 2.2a Structure of the Natural Air 180
Fig. 2.2b Structure of the Natural Air 350
1 Back plate and sides
2 Control panel and display
3 Inspection door
4 Front cover
5 Connection nozzle, extract air
6 Connection nozzle, supply air
7 Connection nozzle, exhaust air
8 Connection nozzle, fresh air
9 Defrost Heater supply output (PH variants only)
*
10 Boost Heater supply output (PH variants only) *
* External Heater boxes (not supplied) are
available
as an accessory. (See User Manual for details).
6

Section 2 –Description of the Device
Natural Air 180
Natural Air 350
Fig. 2.3 Structure in detail
7

Section 2 –Description of the Device / Section 3 –Technical data
Fig. 2.3 Key to structure in detail
1 Rear cover
7 Control PCBs area
13 Control panel and display
2 Actuator cover
8 Filter
14 Heat exchanger cover
3 Bypass actuator assembly
9 Installer connections
15 Filter access door
4 Bypass flap assembly
10 Filter cover
16 Front cover
5 Main EPP body
11 Fan assembly
6 Top cover
12 Heat exchanger
Section 3 –Technical data
3.1 Specification
180 Series
350 Series
Maximum volume flow rate
225 m³/h (62 l/s)
360 m³/h (98 l/s)
Volume flow rate at speed 1/2/3
(30% / 46% / 58%)
75 / 115 / 144 m³/h
(21 / 32 / 40 l/s) *
162 / 243 / 307 m³/h
(45 / 67 / 85 l/s) *
Minimum volume flow rate
40 m³/h (11 l/s)
57 m³/h (16 l/s)
Power supply (5 A fuse)
1~/N/PE/230V 50 hz
148 W
1~/N/PE/230V 50 hz
170 W
Power supply PH versions :
180 series 13A. 350 series 20A.
1~/N/PE/230V 50 hz
2.2 kW
1~/N/PE/230V 50 hz
Up to 4.0 kW **
Power consumption at factory default
Speed 1 / 2 / 3 (No System pressure applied)
15 / 33 / 54 W
15 / 33 / 54 W (PH
model)
15 / 33 / 54 W
23 / 40 / 58 W (PH
model)
Dimensions Width x Height x Depth
550 x 640 x 285 mm
755 x 770 x 615 mm
Weight
19 kg
34 kg
Air duct connector diameter (mm) x 4
125
150 / 160 / 190 / 200
Heat recovery efficiency
up to 89%
up to 89%
Ventilator type
2 x EC-radial,
(all constant volume)
2 x EC-radial,
(PH is constant volume)
Heat exchanger type
Contraflow heat recovery module
Filter Grade
G4 Fresh Air / G4 Extract Air
Bypass (integrated)
Yes
Function for safe use with open flue fuel burners
Yes
Inner housing
Material : Plastic EPP (fire class B2)
Outer casing
Material : White sheet steel (fire class B1)
Protection rating
IP20
Condensate hose connectors
Ø15 mm
Outdoor temperature range for use
-20 to +40°C
Table 3.1 Specifications
NOTE!
* 180 or 350 Factory defaults. Values will need to be changed for each site situation.
** Natural Air 350 rating depends on the power of the Pre-heater and Boost heater (if fitted).
For guidance only (180 Series: K + 3 maximum. 350 Series: K + 7 maximum)
Speed m³/h (l/s)
Speed m³/h (l/s)
Situation
Speed 1
Speed 2
Speed3
Situation
Speed 1
Speed 2
Speed 3
K + 1
75 (21)
115 (32)
144 (40)
K + 5
191 (53)
286 (80)
360 (100)
K + 2
104 (29)
158 (44)
198 (55)
K + 6
220 (61)
330 (92)
360 (100)
K + 3
133 (37)
198 (55)
225 (62)
K + 7
248 (69)
360 (100)
360 (100)
K + 4
162 (45)
243 (67)
307 (85)
8

Section 3 –Technical data
See limitations of Flow Rate vs. External Pressure Loss in the graph below (Fig. 3.2)
3.2 Characteristic curves
180 and 350 Series
Fig. 3.2 Characteristic curves Natural 180 / 350 ranges (Dotted lines represent Factory defaults)
Key to Characteristic curves
①
Speed 1 (180 default)
④
Speed 1 (350 default)
V
Volume flow rate (m3/h)
②
Speed 2 (180 default)
⑤
Speed 2 (350 default)
Δp
External pressure loss (Pa)
③
Speed 3 (180 default)
⑥
Speed 3 (350 default)
NOTE!
Each Supply & Extract speed can be changed using Installer Menu (see 6.3.1)
3.3 Dimension drawings
Key to drawings:
1
Exhaust air duct connection
9
Display and Control panel
2
Fresh air duct connection
10
Filter access door
3
Defrost heater, power outlet *
11
Front cover
4
Boost heater, power outlet *
12
Condensate connection point A
5
Supply air duct connection
13
Condensate connection point B
6
Voltage supply feed
14
Bottom panel
7
External sensor connections
15
Side panel (2 off) c/w 4 side mounting holes
8
Extract air duct connection
16
Back panel c/w 4 back mounting holes
* Only available on Natural Air PH Models
9

Section 3 –Technical data
3.3 Dimension drawings (continued)
Fig. 3.3a Dimensional drawing, Natural Air 180 ventilation unit
10

Section 3 –Technical data
3.3 Dimension drawings (continued)
Fig. 3.3b Dimensional drawing, Natural Air 350 ventilation unit
11

Section 4 –Installation
4.1 Requirements at the installation site
The location must be frost-free.
The room temperature should not fall below +5°C.
The Fresh air intake must be sited in an area free from unwanted odours and far enough away from the
Exhaust air outlet to prevent re-circulation.
The condensate drains must be protected from freezing.
Ensure there is at least 200mm clearance above the top surface of the unit so that the duct connections
are not restricted.
Make sure there is sufficient space around the unit for maintenance and repair work. (See dimensional
drawing).
We strongly recommend you consult a qualified specialist.
Fig. 4.1a Space needed for maintenance MVHR 180 Fig. 4.1b Space needed for maintenance MVHR 350
WARNING:
Free access to the unit and to the switch disconnecting it from the power supply must be ensured
at all times.
NOTE!
Air inlet and outlet openings and air transfer openings must not be obstructed, covered or closed
so that an unhindered airflow is ensured. Settings made by the qualified technician must not be
changed.
WARNING:
Alterations made to the unit or to the installed system as a whole as well as structural alterations
can affect safety; consult a qualified technician.
WARNING:
Using the ventilation unit together with fuel burning devices (e.g. fire places, gas stoves) is subject
to special requirements. Any applicable national as well as regional guidelines and regulations must
be observed.
12

Section 4 –Installation
4.2 Installation of the unit
The ventilation unit cannot be mounted on a floor. Condensation drains must be fitted to the unit. It is
designed to be wall mounted. Below is backplate on the wall, ready for remounting the unit:
Fig. 4.2a Natural Air 180 backplate on the wall
Fig. 4.2b Natural Air 350 backplate on the wall
Remove the front and top cover and take the EPP unit out of the metal backplate.
Offer up the backplate to the wall and mark out the mounting points, ensuring the unit is level.
Secure the backplate to the wall using appropriate fixings.
If installing on a hollow wall, suitable anti vibration fixings may be required.
If required, the unit can be fixed using left and right side fixing holes (E.g. If the unit is fixed inside a
cupboard).
Remount the unit into the backplate and secure the top and front cover.
NOTE!
Check that the unit is positioned level in order to ensure proper condensate discharge.
4.3 Condensate discharge lines
There are two condensation collection trays built into the expanded poly propylene housing (EPP) of the unit
and two (provided) condensate collection unions must be fitted to the discharge points on the bottom side of
the unit.
Remove the front cover from the installed unit. Take care to remove the umbilical connector from the
Display PCB.
Pull out the EPP cover and remove the heat exchanger using the pull strap.
Remove the back-nuts from the condensate unions (provided) and then push them through the two EPP
drain holes. Note: Additional leak proofing of the union may be required.
Secure the two unions to the backplate using the back nuts.
Replace the heat exchanger and EPP cover.
Re-fix the front cover, remembering to reattach the umbilical connector to the Display PCB.
Connect drain hoses to the two unions and take to a suitable drain trap.
NOTE!
The location of the ventilation unit, as well as the condensate discharge hoses, must be frost-free!
When connecting up to the drainage pipe of the building, the following points must be observed:
13

Section 4 –Installation
4.3.1 Air infiltration and Infiltration of sewer gases
Any air infiltration into the ventilation unit via the condensate hose must be prevented.
Both condensate hoses must be looped and inclined as shown in Fig 4.3 in order to trap a loop of water and
prevent air getting back into the unit via the hoses.
(1 metre length of hose is supplied with each unit).
The hoses must go via a funnel or tundish to a suitable water trap as shown below.
The condensate hoses from the ventilation unit must not be connected directly to the drainage pipe.
Fig. 4.3 Condensate drain connection (schematic)
NOTE!
Both condensate hoses MUST be made, and
separately run to their own drain connection.
DO NOT “common up” the two hoses.
1 Ventilation unit
2 Looped to act as a condensate trap
3 Condensate line with downward gradient
4 Funnel or tundish to provide air gap
5 Water trap to prevent bad odours entering the
room
6 Drainage line with min. 2% downward gradient
NOTE!
Pre-fill water traps or installed hose bends after completion.
NOTE!
Ensure that the condensate hoses are sufficiently inclined! Incorrect installation can cause water
damage!
NOTE!
The condensate hoses must be checked and cleaned regularly, at least annually!
4.4 Air duct system
The connection nozzles for the air duct system are on the top side of the unit in the vertical direction.
Fig. 4.4a Natural Air 180 Air duct connections
Fig. 4.4b Natural Air 350 Air duct connections
14

Section 4 –Installation
Key to Figure 4.4 (above) :
1 Fresh air (outside air being drawn in)
NOTE!
Connecting exhaust hoods or vented dryers
to the ventilation unit is not permitted! We
recommend using exhaust hoods with
recirculation and condensation dryers.
2 Supply air (air going into the rooms)
3 Extract air (air extracted from the rooms)
4 Exhaust air (air going into outside space)
The Fresh air (1) & Exhaust air (4) ducts connect ventilation unit to the outer wall screens or ceiling hoods.
The Supply air (2) & Extract air (3) ducts connect ventilation unit to required room grilles, diffusers, dampers.
The ducting should be routed from a distributor, without branching, star-like to its required room.
NOTE!
The air-duct system must be dimensioned and designed in accordance with the requirements of the
building and the ventilation unit chosen (see Section "2.4 System design"). An incorrectly specified
system can lead to insufficient ventilation and can cause high noise levels and an excessive energy
consumption. Any applicable guidelines and regulations must be observed and complied with.
4.4.1 Thermal insulation
The ventilation unit must be installed within the warm space of the building.
Ducts installed in cold spaces must be adequately insulated.
WARNING:
The unit, air diffuser and air-duct system must be installed inside the building.
Connections at both ends of the fresh-air and exhaust-air ducts must be airtight and
covered with thermal insulation over the entire route. (To prevent condensation).
Any ducting that runs through unheated areas must also be fitted with thermal insulation,
in order to prevent heat loss.
4.4.2 Vibration isolation and sound insulation
The final connection to the unit must use flexible ducting to isolate any vibration noise getting into the
system.
If required, suitable silencers/attenuators should be used at appropriate positions in the duct system.
(This may also include suitable sound absorbing suspensions, clamps, brackets or other duct fittings).
Ducting passing through walls or ceilings should be “sealed in” using a suitable material.
Sound travelling through the ducting from one room to another is reduced when a radial duct system is
used.
4.4.3 Air inlets and outlets
Fresh air is drawn in and exhaust air goes out through exterior-wall grilles and/or roof cowls.
The Fresh air is generally cool, dry and free of odours.
The Fresh air draw in point should be at least 1.5 m above ground level if possible.
The Exhaust air point should be positioned far away from the Fresh air inlet. (So that exhaust air does not
accidentally get drawn in to the fresh air intake).
Air inlets and outlets should be positioned in each room so that there is a good air flow through the room.
Position supply grilles so that they avoid direct drafts onto seats, chairs and beds, etc.
For unhindered air flow, areas such as hallways and corridors may require undercut doors or transfer
grilles.
15

Section 4 –Installation
4.5 Electrical installation
Natural Air 180/350 and Natural Air 180/350 Plus :
Connect the ventilation unit to a 230V/50Hz power supply, 5A fuse protection.
Natural Air 180 PH :
Connect the ventilation unit to a 230V/50Hz power supply, 13A fuse protection.
Natural Air 350 PH :
Connect the ventilation unit to a 230V/50Hz power supply, 20A fuse protection.
Note : Natural Air 350 PH rating depends on the power of the Pre-heater and Boost heater (if fitted).
Optional sensors use a low voltage of 24V DC.
All cable inlets are located on the top cover of the ventilation unit.
4.5.1 Installation of the smoke detector bypass Link Wire
If an external smoke detector is NOT used, then a Link Wire MUST be fitted to the Main Connector PCB.
(Alternatively, if the External Sensors PCB is fitted, then the Link Wire can be fitted to the External Sensors PCB
instead).
Fig 4.5a Link wire fitted to Main Connector PCB
Fig 4.5b Link wire fitted to External Sensors PCB.
(See Section 4.5.8 if an external smoke detector sensor is required).
16

Section 4 –Installation
4.5.2 Connecting the ventilation unit to the power supply, external
sensors and heaters
Fig. 4.6a Cable inlets on the Natural Air 180 unit
Fig. 4.6b Cable inlets on the Natural Air 350 unit
Key to parts :
1 Cable inlets for sensors
Remove a grommet and
make a suitable hole
through the exposed EPP
insulation to the wiring
chamber.
2 Cable inlet for power supply
On all 350 models the mains
supply connection is made
inside the Power outlet
termination box.
3 Pre-heater, Power outlet *
4 Boost-heater, Power out *
* Only available on PH Models
Wiring power supply to Main terminal block:
NOTE!
The installer must fit the power connection with an all-pole mains switch with a contact separation
of at least 3 mm.
WARNING:
Install and secure the mains cable through the cover cable gland. Ensure that the bare cable ends
are correctly and tightly secured into the mains supply terminal block.
WARNING:
Electrical connections must be installed by a qualified technician in compliance with all safety rules
for electrical equipment and with all applicable standards and local regulations as well as in
accordance with the installation manual. Before starting any work on the unit, the power supply
must be disconnected in order to prevent any electrical hazard.
17

Section 4 –Installation
Fig. 4.7a Wiring configuration: PCB Termination
for all Natural Air 180 & 350 units.
(except 350 PH –see Fig. 4.7b)
Fig. 4.7b Wiring configuration: Termination
for Natural Air 350 PH units only.
(Note : Pre-heater and Boost Heater outputs
are only available on the Natural Air PH
models)
4.5.3 Electronics boards in the ventilation unit
The ventilation unit is equipped with several boards.
The mains voltage supply is connected to the EMC Terminal Block PCB on the Natural Air 180 units.
The mains voltage supply is connected to the Installer Terminal Box on the top of the Natural Air 350 units.
An external Smoke alarm and Flue detection controls can be connected to the Main Connector PCB.
An optional External Sensors PCB is required on the Natural Air models, if external sensors are used.
(Spare part, 42273SK –See User Manual).
(Note : The External Sensor PCB is fitted as standard to the Natural Air Plus and Natural Air PH Models)
To make connection easier, the boards can be removed from the housing.
18

Section 4 –Installation
Fig. 4.8 Main Connector PCB External Sensors PCB
Key to connections :
L2
Connection to 4 internal temperature
sensors
X1 block 1
to 7
External 0 –10V output Humidistat
sensors.
(Model 180V - Only 1, 2 and 3 available)
L3
External Volt free smoke detector
input
X1 block
CO2 sensor
External 0 –10V output CO2 sensor
L6
Connection point to internal humidity
sensor
X2 block
AQS 1
External 0 –10V output AQS 1 sensor
L7
Connection point to External sensors
PCB
X2 block
Smoke
External Volt free smoke detector input *
L16
Connection point to Main Logic PCB
X2 block
Volt free 1
External Volt free configurable input 1
L17
External Flue Detection 1 : Volt free
input
X2 block
Volt free 2
External Volt free configurable input 2
L17
External Flue Detection 2 : Volt free
input
X3 block
Sensor 2
Internal 0 –10V output AQS 2 sensor.
(When fitted)
* Note : Do not use this input for Smoke Detection if a smoke detector device is already connected to L3 on
the Main Connector PCB.
19

Section 4 –Installation
4.5.4 Electrical circuit diagram : Natural Air 180
Fig. 4.9a Electrical circuit diagram, internal wiring Natural Air 180
NOTE!
Defrost Power, Boost Power output and external NTC available on Natural Air PH Models only.
External Sensors PCB on Natural Air Plus Models only. (Other models, available as an accessory).
20