2
nuaire.co.uk
029 2085 8400
04. 11. 19. Leaflet Number 671859
Installation and Maintenance
MRXBOXAB-ECO2-AESW Mechanical Ventilation Unit with Heat Recovery
2.3 Option 1: Wall Mounting
The MVHR unit fixed to a solid wall construction using the
mounting bracket provided.
2.4 Option 2: Wall Mounting
If it is not practical to use a solid wall, the unit should be fixed to a
stud partition with a 25mm minimum thickness MDF panel solidly
fixed behind the plasterboard.
If fixing to a stud wall the MDF panel should extend, width wise, over
a minimum of 3 vertical studs with centres of no more than 400mm.
A vertical stud should be located to correspond with the position each
mounting bracket is to be fixed to provide additional support.
Add additional vertical supports if necessary. Height wise, the MDF
panel should extend from floor to ceiling.
Fix the mounting bracket to the wall (as fig. 4) and use the wall
mounted bracket to mount the unit on (as shown in fig. 6).
Ducting in the
ceiling void.
Side view of unit
mounted on the
block wall in a
cupboard using
MVHR-DRAIN
the wall brackets.
Condensate drain,
uninsulated drain
pipe with min 5
o
fall
running to SVP.
Valve in ceiling.
Unit weight
= 45kG
Figure 5. Typical example of a cupboard mounted unit (Standard
unit) fixed to a block work wall.
Ducting in the
ceiling void.
Side view of unit
mounted in a
with the 25mm
cupboard fixed to
a stud partition
MDF fixed behind
the plasterboard
using the wall
MVHR-DRAIN
brackets.
Condensate drain,
uninsulated drain
pipe with min 5
o
fall
running to SVP.
Valve in ceiling.
Unit weight
= 45kG
Figure 6. Typical example of a cupboard mounted unit (Standard
unit) fixed to a stud partition with the MDF panel fixed behind the
plasterboard.
2.5 Condensate Drain
The MVHR unit inside the enclosure is fitted with a straight coupling to
allow 21.5mm overflow pipe (not supplied) to be attached using solvent
cement, the pipe should be passed through the flexible adhesive backed
cover plate before the solvent cement is applied.
The pipe can then be inserted into the coupling of the MVHR unit and
the cover plate slid along the length to bond against the base panel of
the enclosure preventing noise breakout (fig. 7).
1. The condensate must be discharged under a water level in a U-trap
drainpipe or an alternative drain method which acts as an airlock.
2. This condensate discharge connection is suitable for 21.5mm dia.
overflow pipe. Solvent cement should be used to make the joint.
3. If using a U-trap please ensure the U-trap has been filled to a
suitable level of water to avoid any air locks.
4. If the condensation pipe is fitted in an unheated space the pipe
should be in insulated to prevent freezing.
Nuaire recommend MVHR-DRAIN be used as the primary
condensate take-off. (see figure 9 and 10).
Min 5
o
Drop
Collar
To SVP
“T” piece
MVHR Drain
To unit
To CONTRAP
Solvent cement to be applied
Flexible adhesive backed
cover plate
Overflow pipe
Figure 7.
Figure 8. Wet option:
Condensate pipe connection
to unit and a typical
example of a “U” trap
drainpipe
(Standard
configuration only).
Figure 9. MVHR-DRAIN option: Condensate
drain, uninsulated drain pipe with min 5° fall
running to SVP.
Figure 10. IMPORTANT: When using a “T” Piece to connect the
CONTRAP drainage and the MVHR drain pipework the MVHR
drain must always be fitted before the “T” Piece to prevent
condensate from feeding back into the MVHR system.
