4
23. 07. 20. Document Number 671856
Nuaire |
Western Industrial Estate
|
Caerphilly
|
CF83 1NA
|
nuaire.co.uk
MRXBOXAB-ECO(3/5)-(OH)SW
Installation Manual
3.3 Condensate Drain
The condensate must be discharged under a water level in a U-trap
drainpipe or an alternative drain method which acts as an airlock. This
condensate discharge connection is suitable for 21.5mm Ø overflow
pipe. Solvent cement should be used to make the joint.
If using a U-trap please ensure the U-trap has been filled to a suitable
level of water to avoid any air locks. If the condensation pipe is fitted in
an unheated space the pipe should be in insulated to prevent freezing.
An MVHR-DRAIN is recommended for use as the primary
condensate take-off (Figures 10 and 11).
Min 5
o
Drop
Collar
To SVP
“T” piece
MVHR Drain
To unit
To CONTRAP
9
10
11
Condensate Trap Installation
MVHR-DRAIN Installation
"T" Piece CONTRAP & MVHR Drain Connection
Condensate drain,
uninsulated drain pipe with
min 5° fall running to SVP.
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.
Condensate pipe connection to
unit and a typical example of a
“U” trap drainpipe
(Standard
configuration only).
3.4 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).
External grilles are to have a minimum free area of 12,250 sq. mm.
ADF 2010 - Extract Ventilation Rates
Room
Minimum High rate
Minimum Low Rate
Kitchen
13 l/s
Total extract rate
should be at least
the whole dwelling
ventilation rate given
in table 2.
Utility Room
8 l/s
Bathroom
8 l/s
Sanitary
Accommodation
6 l/s
Whole Dwelling Ventilation Rates
Number Of Bedrooms In Dwelling
1
2
3
4
5
Whole dwelling
ventilation rate
(l/s)
1,2
13
17
21
25
29
Notes:
1. In addition, the minimum ventilation rate should be no less than 0.3
l/s per m² of internal floor area. (This includes all floors, e.g. for a two-
story building add the ground and first floor areas).
2. This is based on two occupants in the main bedroom and a single
occupant in all other bedrooms. This should be used as the default
value. If a greater level of occupancy is expected add 4 l/s per occupant.
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.
3.5 Ducting
Before commencing ducting installation reference should be made
to building regulations document “Domestic ventilation compliance
guide”. This document supports ADF2010 and details installation,
testing and commissioning of all ventilation systems.
It is recommended that rigid ducting be used at all times. Flexible
ducting has a very high resistance and it is impossible to calculate how
much resistance will be on a system if used.
If used the flexible ducting must be kept to a minimum and should
always be pulled taut. A maximum of 300mm should be used on each
leg.
To prevent condensation on the outside of the outside air inlet 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 distance of 300mm between the appliance and any bends
in ductwork is recommended.
Ideally 150mm diameter or 204 x 60mm rectangular ducting should be
used (Figures 13 & 14).
Ducting joints must be sealed with silicone type sealant and shall be
adequately and reliably fixed to the appliance.
3.6 Ventilation Flow Rates
