NuAire MRXBOX95ABWM2QA12338 Installation And Maintenance Manual Download Page 1

The unit must remain switched on at all times to maintain ventilation within
the dwelling. Turning the unit off will cause long term damage to the unit
and building fabric.

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 the use of the appliance by a person for their safety. Children
should be supervised so that they do not play with the appliance.

Installation and Maintenance

MRXBOX95ABWM2QA12338

Mechanical Ventilation Units with Heat Recovery for Wall

 

Mounting

Nuaire Limited

Western Industrial Estate  Caerphilly  United Kingdom  CF83 1NA 

T: 029 2085 8400  F: 029 2085 8444  E: info@nuaire.co.uk  W: www.nuaire.co.uk

1

10. 06. 16. Leaflet Number 671752

Spigot fixing plate

Transportation fixings

Figure 1. Airflow through unit (Standard unit).

Figure 2. Airflow through OH unit (Opposite hand unit).

Intake air 
from outside

Extract air 
from house

Supply air 
to house

Exhaust air 
from house
to outside

Extract air 
from house

Intake air 
from outside

Exhaust air 
from house
to outside

Supply air 
to house

1.0 Introduction

The WM2-1Z wall mounted range of units are designed to offer
improved sound levels and an aesthetically pleasing installation by
housing a Mechanical Ventilation with Heat Recovery unit (MVHR)
and attenuator inside an acoustically lined enclosure.

The MVHR unit is fitted with two independent fans. Each fan has full
speed control for background and boost ventilation rates. To recover
heat from the extract air the heat exchanger block is utilised. The heat
exchanger can recover up to 95% of the normally wasted heat.

If the MVHR unit has integral automatic summer bypass 
(AB models only) 

The bypass damper shall open automatically via 

a wax actuator allowing the air to bypass the heat exchanger to 
deliver fresh filtered air during the warmer months.

2.0 Installation

Installation must be carried out by competent personnel in accordance
with the appropriate authority and conforming to all statutory 
governing regulations. All mains wiring must be in accordance with the
current I.E.E. Regulations, or the appropriate standards. Ensure that the
mains supply (Voltage, Frequency and Phase) complies with the rating
label. 

Please allow a minimum of 350mm in front of the unit.

The fan must be installed indoors, on a suitable wall away from direct
sources of frost, heat, water spray or moisture generation. 
For a vibration-free result the unit must be mounted to a non-
reverberant wall.

2.1 Transportation fixings

To prevent damage during transportation the product is shipped
with securing fixings, these can be found front and centre of the
enclosure top panel (fig.3).  These must be removed before use, fail-
ure to do so will result in excessive vibration and noise.  The screws
removed can be discarded and replaced with rubber caps provided.

Figure 3. Securing fixings.

2.2 Wall Mounting the MVHR Unit

The unit is designed for wall mounting only on a solid wall, a gypsum
block/plasterboard wall will not suffice, examples of suitable 
installation are shown overleaf. The wall brackets supplied should be
secured to the wall using suitable fixings (supplied by others) as per
the dimensions given in fig.4, the head of the chosen fixing should
protrude no more than 8mm from the wall bracket. The enclosure
assembly can then be lifted using suitable equipment and moved into
position so it is sitting directly on the wall brackets (ensuring the rear
panel of the enclosure is not in contact with the wall bracket fixings).
The enclosure can be secured to the wall brackets using the 4x M8 
fixings supplied. 

No part of enclosure should be in contact with the building structure,
the only components that should be in contact are the wall mounting
brackets.

Figure 4. Dimensions for fitting wall brackets.

Note: Care must be taken to ensure the unit is installed true in all 3 
dimensions. Failure to do so may result in overflow from the internal 
condensation drip tray.

The EMC Directive 
2014/30/EU  
The Low Voltage 
Directive 
2014/35/EU

640

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Summary of Contents for MRXBOX95ABWM2QA12338

Page 1: ...ion must be carried out by competent personnel in accordance with the appropriate authority and conforming to all statutory governing regulations All mains wiring must be in accordance with the curren...

Page 2: ...d the cover plate slid along the length to bond against the base panel of the enclosure preventing noise breakout fig 7 Figure 7 1 The condensate must be discharged under a water level in a U trap dra...

Page 3: ...t duct and the air outlet duct from the unit these ducts should be insulated Ducting must be installed in such a way that resistance to airflow is minimised Bends should be kept to a minimum A minimum...

Page 4: ...ADF 2010 can be used where security is not an issue In this case minimum high extract rate for the sanitary accommodation should be omitted from the step 2 calculation Step 3 The required airflow rate...

Page 5: ...ply duct Air supply to lounge via Air Valve in ceilings Extract air from kitchen bathroom via Air Valve in ceilings Air supply to bedrooms via Air Valve in ceilings Top of ceiling void Top of ceiling...

Page 6: ...upply Extract Extract Trickle Boost Trickle Boost CN5 Connection to Remote Fail Indicator Ref MRXBOX95LH RFI Optional 3 2 Figure 11a Note Wiring is for reference purposes only as the connections in fi...

Page 7: ...e set point the unit will boost to that set by the commissioned boost speed The set point can be found on the front of the unit see Fig 14 and is at its least sensitive when turned fully clockwise Not...

Page 8: ...ctrically competent person When ordering spare parts please quote the serial number of the unit and the ARC number of the purchase if possible This information will be available on the fan label 11 0...

Page 9: ...ings assessed under The Building Regulations 2010 specifically SAP 2009 and Approved Documents L and F Completion of this document is therefore only required for dwellings assessed by SAP 2005 Custome...

Page 10: ...r to overcome particular obstructions If flexible ducting has been used has it been pulled taut to minimise system resistance Has the number of duct bends been minimised to ensure adequate air flow an...

Page 11: ...y unit been fixed to a stable element of the building fabric e g wall or floor using manufacturer recommended supplied fixing brackets Has the condensation drain been fitted and the pipe insulated Hav...

Page 12: ...or N A Has the rating label been verified to establish suitability for the installation strategy and whether an earth is required e g voltage class I or II product status Has a local isolator been pro...

Page 13: ...tion grilles been locked where possible to minimise unapproved occupant adjustment Figure 3 Ensure all external and internal windows and doors are closed Set fan speed using manufacturer data table Se...

Page 14: ...e customer been advised that opening windows is not recommended during normal use in order to ensure the energy efficient operation and performance of the balanced system Has the customer been advised...

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