Installation And Maintenance; Condensate Drain - Nuaire Group MRXBOX95B-LOFT Installation And Maintenance Manual

Installation and Maintenance

Installation cont.
Figure 2b. Mounting MRXBOX95B-LOFT onto roof joists using the 'L' shaped fixing
brackets and AV mounts with four suitable screws on the short side of the unit.
Two fixing brackets
should be attached on
the non-control end of
the unit via the two
upper hole positions.
(see figure 2c).
21.5mm dia.
condensate pipe.
The two fixing brackets on the control end of the MRXBOX95 unit should be attached via the two
lower hole positions. (see figure 2c).
Figure 2d. Unit viewed from the front mounted at a slight angle.

2.1 Condensate Drain

1. Remove top cover and remove heat exchanger.
The condensate outlet can then be seen at the base of
the unit. Using a 90 Deg bend and suitable length of
¾" / 21.5mm diameter overflow pipe (not supplied) take
the condensate to the outside of the unit (can be taken
to either side of the unit as required).
Suitable adhesive should be used for all connections.
2. The drain should run through a secondary trap before
being discharged through the eaves or into the waste
water system.
3. Pour a little water into the drip tray to create an air trap.
Figure 3. Plan view of unit
showing drip tray and
condensate drain.
Drain Tray
MRXBOX95B-LOFT Mechanical Ventilation with Heat Recovery & Summer Bypass
21.5mm dia.
condensate
drain alternative
position
21.5mm dia.
condensate drain
Figure 2c. Side and front view example of
an 'L' shaped fixing bracket and AV mount
attached to ceiling joist.
Controls
2.2 Extract/input areas
The unit is designed to extract air from all wet rooms
e.g. bathroom, kitchen, en-suite, utility room (with sink).
WC's do not need to be ventilated if openable windows are
fitted. Supply air should be to all habitable rooms e.g. bedrooms
and lounge. Extract / input grilles should be adjustable valve
types (not supplied).
2.3 Ducting
1. If the unit has been specified as SAP appendix Q installation
the use of flexible is prohibited. If flexible ducting is to be
used it should be kept to a minimum and should always be
pulled taught.
2. The unit is supplied with 150mm and 125mm outlets. It is
recommended that 150mm ducting be used from outside to
the unit and 125mm used from the unit to the dwelling
rooms. To prevent condensation on the ducting they should
be insulated externally vapour-proof as far as the unit.
3. Ducting layout plans should be adhered to if available.
4. It is recommended the 204 x 60mm ducting be used and the
number of 90 Deg bends be kept to a minimum.
5. Ducting joints must be sealed with duct tape and/or silicone
sealant.
For further information refer to Building Regulations Part F
and BRE appendix Q website.
Any air intake terminal MUST be installed in accordance
with the appropriate regulation.
As a guide, the BS5440 series of British Standards
deals with this issue and currently states that an air
intake must be at a minimum distance of 300mm from
a gas boiler balanced flue. Installers are advised to
be aware of the requirements of this standard when
installing 'through the wall' supply air ducting.
Similarly, supply and extract air grilles should be at
least 300mm apart.
2
Higher and lower
mounting hole positions
Metal bracket
attached to unit
Washer Woodscrew
A. V. mount
Ceiling joist
Leaflet Number 671453 January 2011