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18. 02. 21. Document Number 671876
Nuaire | Western Industrial Estate | Caerphilly | CF83 1NA | nuaire.co.uk
MRXBOXAB-ECO-LP2SW
Installation Manual
4.3.2 Unit Serving Kitchen & 2 Bathrooms
4.3.3 Summer / Winter Switch
Black
2 core cable
from unit
Red
Volt free Summer / Winter Switch (supplied with unit)
Polarity is inconsequential
Warning! - Do not connect to mains!
14
Wiring Diagram - Summer / Winter Switch
5.0 COMMISSIONING
The filters fitted inside the unit are protected with a plastic film.
Prior to commissioning remove the covers (Figure 15), take off the
film and replace.
•
For the required air flow rates please refer to the design
specification for the property, follow Section 3.5, or refer to
building regulations ADF 2010.
•
The unit is supplied with independent control for both normal and
boost airflows (Figure 15).
•
Correct commissioning is essential to ensure the ventilation air
flowrates are met. It also ensures the unit is not over ventilating
and causing excessive power consumption.
•
Commissioning should be carried out in accordance with building
regulations document “Domestic ventilation compliance guide”.
A calibrated moving vane anemometer and hood will be required
to carry out commissioning.
•
Adjustment valves should be locked in place to prevent further
adjustment.
•
Once commissioned the home owner / tenant should be informed
that the unit should not be adjusted as it will have a detrimental
effect on the indoor air quality and could result in condensation
and mould growth. The label covering the control has an adhesive
panel which should be removed post commissioning to prevent
tampering.
Control module
Speed 1
Speed 2
Speed 1
Speed 2
15
Commissioning Controls
6.0 CONTROLS
6.1 Integral Automatic HX Bypass (AB Units Only)
Intake and extract temperatures are monitored at the point the
airflows enter the unit, if the range falls within the set parameters the
bypass damper is opened automatically to target an indoor comfort
temperature all year round.
6.2 Summer / Winter Switch
When the switch position is set to Summer, the integral automatic
summer bypass is fully operational. In the alternative Winter position,
the HX bypass is disabled to ensure the unit is constantly in heat
recovery mode.
6.3 Speed 3 Operation (SW Units Only)
Speed 3 will be non-operational if the intake temperature is greater
than the extract temperature.
6.4 Frost Protection
In the event of the intake air temperature at the unit dropping below
the predetermined set point (-5°C as standard) the supply fan will
reduce to minimum speed, once the temperature rises above the set
point the fan will return to its commissioned speed.
This mode will only activate after ten days of continuous run time.
If commissioning of the unit is outside of this time frame please
notify the after sales department prior to site visit.
Disconnection from the
supply mains must be
incorporated within the
fixed wiring in accordance
with the wiring
regulations and shall
have a minimum contact
separation of 3mm.
3A Fuse
(BS 1362)
MAINS
230V
50Hz
Room
Lights
Light
Switches
(Double
Pole)
N
L
3 Pole
Isolator
Kitchen Switch
Blue
Green / Yellow
Brown
Black
Supply Cord
From Unit
Optional 3 Speed Switch
Grey
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Wiring Diagram - Kitchen & 2 Bathrooms
