7
nuaire.co.uk
029 2085 8400
04. 11. 19. Leaflet Number 671859
Installation and Maintenance
MRXBOXAB-ECO2-AESW Mechanical Ventilation Unit with Heat Recovery
+
-
Post commissioning remove
adhesive backing and seal
Power Fan
Failure
+
-
Ventilation Controls
- +
+
- +
-
Speed 1
- +
Speed 2
Speed 3
Supply Extract Supply Extract Supply Extract
Humidity adjustment
6.0 COMMISSIONING
IMPORTANT
The filters fitted inside the unit are protected with a plastic film.
Prior to commissioning remove the covers (figs. 15 & 16), take off the
film and replace.
1. For the required air flow rates please refer to the design specification
for the property, follow 2.4, or refer to building regulations ADF
2010.
2. The unit is supplied with independent control for both normal and
boost airflows (see fig. 18).
3. Correct commissioning is essential to ensure the ventilation air flow
rates are met. It also ensures the unit is not over ventilating and
causing excessive power consumption.
4. Commissioning should be carried out in accordance with building
regulations document “Domestic ventilation compliance guide”.
www.planningportal.gov.uk/building regulations/approved
documents/partf/associated
A calibrated moving vane anemometer and hood will be required to
carry out commissioning.
5. Adjustment valves should be locked in place to prevent further
adjustment.
6. 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 clear panel covering the control has an adhesive
panel which should be exposed and sealed post commissioning to
prevent tampering.
7. Speed 1 is limited to never exceed speed 2, when commissioning
speed 2 should always be set first.
Figure 18. Detail of unit control
on front panel
(standard
configuration only).
6.1 Humidity adjustment
This product contains an internal humidity sensor fitted into the air-
flow extracting from the wet rooms. When the unit senses that the
humidity exceeds the 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. 18) and is at its least sensitive when turned fully
clockwise. Note that the sensor is measuring humidity from all the wet
rooms at the same time and should not be relied on to solely boost
the unit. Additional switch should be used local to the wet rooms (see
wiring diagrams).
Nuaire recommend that filters are inspected every 6 months and
replaced every 12 months. A flashing LED (section 7.0) will indicate that
a filter change is required. This indication repeats every 12 months and
will turn off automatically after 5 Days.
Remove the filter covers on the front panel of the unit by gripping the
two circular tabs either end of the filter covers and pulling away from
the unit. The filter can now be extracted by pulling the removal loop on
the front edge of the filter. Once the filters have been inspected return
or replace them as necessary.
Inspect the heat exchanger every 5 years. Generally check for damage
and security of components. Refit cover.
7.0 STATUS INDICATION
The status of the unit is indicated by a series of LED’s on the front cover.
The variants are listed below.
HX Bypass
(AB units only)
Speed 1
Speed 2
Speed 3
Supply Fan Fault
Extract Fan Fault
Frost Protection
Filter Change
IMPORTANT
Isolation - Before commencing work make sure that the unit,
switched live and control are electrically isolated from the mains
supply and switched live supply.
8.0 INTEGRAL AUTOMATIC HX BYPASS
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.
8.1 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.
8.2 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.
Please note 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.
9.0 MAINTENANCE
Note: The display on the unit control panel will not indicate when a
higher speed setting has been triggered by an external source, such
as an ES-PIR2 etc.
