Nuaire MRXBOX95-WH1 (MRXBOX-ECO3) Compatible Replacement Filter Set - G3
£18.00
MVHR unit guide
Nuaire MRXBOX95-WH1: specifications, filters & guide
MVHRNuaire
Wall-mounted Nuaire MVHR unit with two independent fans and four 150 mm spigots, stated to recover up to 95% of the heat normally lost from extract air.
- Two independent fans
- Heat exchanger
- Interlocking wall bracket
- Standard and opposite-hand versions
- Speed 3 override
About the Nuaire MRXBOX95-WH1
The Nuaire MRXBOX95-WH1 is a wall-mounted mechanical ventilation unit with heat recovery, part of Nuaire’s WH1 range. It extracts moist air from wet rooms such as the kitchen, bathroom, en-suite and a utility room with a sink, and supplies filtered fresh air to habitable rooms such as bedrooms and the lounge. A heat exchanger passes heat from the outgoing extract air to the incoming air, and the manufacturer states that it can recover up to 95% of the heat that would otherwise be wasted. The system is designed to run continuously, so the unit must stay switched on at all times; turning it off can cause long-term damage to the unit and the building fabric.
Inside the casing are two independent fans, one for supply and one for extract, each with speed control for background and boost ventilation. Nuaire describes the WH1 system as designed for medium to large new build properties. Air enters and leaves through four 150 mm spigots on the top of the casing, and the unit hangs on an interlocking wall bracket. It needs a solid wall, or a stud partition backed by 25 mm MDF, and it can also be mounted in a loft space on an anti-vibration tray. Condensation from the heat exchanger is piped away through a condensate connection that must discharge through a trap or an equivalent airlock.
The installation manual covers four versions: the standard MRXBOX95-WH1, the opposite-hand MRXBOX95-WH1-OH, and the MRXBOX95AB-WH1 and MRXBOX95AB-WH1-OH, which add an integral automatic summer bypass and a humidity sensor with an adjustable set point. On the non-AB versions, the supply fan instead reduces to a trickle speed in excessive outside temperatures. An optional speed 3 switch overrides both speeds to run the fans at maximum airflow.
The two filters sit behind removable covers on the front panel. They are G3 filters measuring 188 x 413 mm, inspected after six months and replaced every 12 to 18 months; filters of this size are also available in G4 and M5 grades. The heat exchanger should be inspected every five years, and the five-year warranty is conditional on planned maintenance being carried out.
Key specs
- Heat recovery (manufacturer's stated figure)
- Up to 95% of the normally wasted heat
- Fans
- Two independent fans (supply and extract), each with full speed control for background and boost rates
- Speed settings
- Speed 1 and speed 2 per fan, plus speed 3 override to maximum airflow; speed 1 is limited to never exceed speed 2
- Summer bypass, AB models
- Integral automatic bypass operated by a wax actuator
- Summer behaviour, non-AB models
- Supply fan reduces automatically to trickle speed in excessive outside temperatures
- Height
- 623 mm
- Width
- 658 mm
- Depth
- 432 mm
- Minimum clear space in front, MRXBOX95-WH1
- 430 mm
- Spigots
- 4 x 150 mm diameter, on the top of the unit
- Recommended ducting
- 150 mm diameter circular or 204 x 60 mm rectangular, rigid ducting preferred
- Maximum flexible duct
- 300 mm on each leg, pulled taut
- Distance from unit to first duct bend
- Minimum 300 mm recommended
- External grille free area
- Minimum 12,250 mm²
- Condensate connection
- Suitable for 21.5 mm diameter overflow pipe, solvent cement joint; discharge under a water level in a U-trap or equivalent airlock
- Condensate pipe fall
- Minimum 5° fall to the soil and vent pipe when using MVHR-DRAIN
- Supply
- Single phase, 50 Hz
- Current consumption
- 1.3 A
- Fuse rating
- 3 A
- Mains connection
- Supplied with a flexible cord (2 m pre-wired fly lead); connect to a fixed wiring installation via a fused isolator with minimum 3 mm contact separation; unit must be earthed
- Filters fitted
- Two removable G3 filters, accessed from the front panel
- Filter size
- 188 x 413 mm
- Grades available in this size
- G3, G4 and M5
- Replacement filter part number
- 778651
- Filter service interval
- Inspect after 6 months; replace every 12 to 18 months
- Status indication
- LEDs for speed 1, speed 2, speed 3, supply fan fault, extract fan fault, frost protection, filter change and (AB units) HX bypass
- Humidity sensor, AB models
- Internal sensor in the extract airflow with adjustable set point; least sensitive when turned fully clockwise
- Optional controls
- Speed 3 switch; Ecosmart sensor connector on the base of the unit; remote fail indicator MRXBOX95-RFI
- Directives
- EMC Directive 2014/30/EU; Low Voltage Directive 2014/35/EU
Replacement filters for the Nuaire MRXBOX95-WH1
Nuaire MRXBOX95-WH1 (MRXBOX-ECO3) Compatible Replacement Filter Set - G4
£19.50
Nuaire MRXBOX95-WH1 (MRXBOX-ECO3) Compatible Replacement Filter Set - M5
£23.00
How to change the filters
- Isolate the unit
Electrically isolate the unit, the switched live and any Nuaire control from the mains and switched live supply, then allow at least two minutes for the fans to come to rest before removing any panel.
- Remove the two filter covers
Take hold of the circular tab at each end of the filter covers on the front panel and pull the covers out.
- Draw out each filter
Pull the removal loop on the front edge of each filter (the black tab on the visible end) to extract it from the unit.
- Inspect the filters
Check each filter. Return it if it is serviceable, or replace it; the filters are inspected after 6 months and replaced every 12 to 18 months.
- Clean or replace
Clean a reusable filter with a vacuum cleaner, or fit a new filter (G3, 188 x 413 mm).
- Refit the filters
Slide the filters back into the unit.
- Refit the filter covers
Replace the two filter covers and secure the tabs, then restore the power supply.
Manuals & downloads
Other MVHR units
MVHRVent-Axia Sentinel Kinetic High Flow Specs, Manual, Fault Codes & Filters
MVHRVent-Axia Sentinel Kinetic V, B and BH Specs, Manual, Fault Codes & Filters
MVHRVectaire WHHR-Midi-BY, Midi-BY-LCD, Midi-BY-AT-LCD Specs, Manual, Fault Codes & Filters
MVHRVent-Axia Sentinel Kinetic Plus B Specs, Manual, Fault Codes & FiltersNuaire and all other manufacturer and product names, model numbers and part numbers on this page are the property of their respective owners and are used for identification only. MVHR.shop is an independent supplier of compatible filters. We are not affiliated with, endorsed by, sponsored by or approved by Nuaire or any other manufacturer named on this page.
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Specifications
Performance
- Heat recovery (manufacturer's stated figure)
- Up to 95% of the normally wasted heat
- Fans
- Two independent fans (supply and extract), each with full speed control for background and boost rates
- Speed settings
- Speed 1 and speed 2 per fan, plus speed 3 override to maximum airflow; speed 1 is limited to never exceed speed 2
- Summer bypass, AB models
- Integral automatic bypass operated by a wax actuator
- Summer behaviour, non-AB models
- Supply fan reduces automatically to trickle speed in excessive outside temperatures
Dimensions & weight
- Height
- 623 mm
- Width
- 658 mm
- Depth
- 432 mm
- Minimum clear space in front, MRXBOX95-WH1
- 430 mm
Connections & ducting
- Spigots
- 4 x 150 mm diameter, on the top of the unit
- Recommended ducting
- 150 mm diameter circular or 204 x 60 mm rectangular, rigid ducting preferred
- Maximum flexible duct
- 300 mm on each leg, pulled taut
- Distance from unit to first duct bend
- Minimum 300 mm recommended
- External grille free area
- Minimum 12,250 mm²
- Condensate connection
- Suitable for 21.5 mm diameter overflow pipe, solvent cement joint; discharge under a water level in a U-trap or equivalent airlock
- Condensate pipe fall
- Minimum 5° fall to the soil and vent pipe when using MVHR-DRAIN
Electrical
- Supply
- Single phase, 50 Hz
- Current consumption
- 1.3 A
- Fuse rating
- 3 A
- Mains connection
- Supplied with a flexible cord (2 m pre-wired fly lead); connect to a fixed wiring installation via a fused isolator with minimum 3 mm contact separation; unit must be earthed
Filters
- Filters fitted
- Two removable G3 filters, accessed from the front panel
- Filter size
- 188 x 413 mm
- Grades available in this size
- G3, G4 and M5
- Replacement filter part number
- 778651
- Filter service interval
- Inspect after 6 months; replace every 12 to 18 months
Controls & features
- Status indication
- LEDs for speed 1, speed 2, speed 3, supply fan fault, extract fan fault, frost protection, filter change and (AB units) HX bypass
- Humidity sensor, AB models
- Internal sensor in the extract airflow with adjustable set point; least sensitive when turned fully clockwise
- Optional controls
- Speed 3 switch; Ecosmart sensor connector on the base of the unit; remote fail indicator MRXBOX95-RFI
Approvals & compliance
- Directives
- EMC Directive 2014/30/EU; Low Voltage Directive 2014/35/EU
Model variants
- MRXBOX95-WH1-OH
Opposite-hand version of the standard unit; the airflow arrangement is mirrored - MRXBOX95AB-WH1
Adds an integral automatic HX bypass (wax actuator) and an adjustable humidity sensor; standard handing - MRXBOX95AB-WH1-OH
Opposite-hand version of the AB unit, with integral automatic HX bypass and humidity adjustment
Nuaire MRXBOX95-WH1 part numbers
Unit models
| Part no. | Description | Notes |
|---|---|---|
MRXBOX95-WH1 | Wall mounted MVHR unit, standard unit | Standard handing; no integral automatic bypass |
MRXBOX95-WH1-OH | Wall mounted MVHR unit, opposite hand | Opposite handing; no integral automatic bypass |
MRXBOX95AB-WH1 | Wall mounted MVHR unit with integral automatic HX bypass, standard unit | Standard handing; includes humidity adjustment |
MRXBOX95AB-WH1-OH | Wall mounted MVHR unit with integral automatic HX bypass, opposite hand | Opposite handing; includes humidity adjustment |
Filters
| Part no. | Description | Notes |
|---|---|---|
778651 | Replacement filters for the MRXBOX95-WH1 | G3 grade, 188 x 413 mm; filters of this size are available in G3, G4 and M5 |
Controls & sensors
| Part no. | Description | Notes |
|---|---|---|
MRXBOX95-RFI | Remote fail indicator for the WH1 units | Optional; connects to the fail terminals |
MRXBOX-JB | Junction box for connecting more than one Ecosmart sensor | Installation instructions in leaflet 671700 |
Accessories
| Part no. | Description | Notes |
|---|---|---|
SIL-WH1 | Silencer for MRXBOX95(AB)-WH1 units | Four airflow chambers; part of the acoustic solution system |
FF-WH1 | First fix plenum chamber for MRXBOX95(AB)-WH1 units | Four 204 x 60 mm rectangular spigots (two each side); four hanging brackets |
AV-WH1 | Anti-vibration tray assembly for loft space mounting of the WH1 units | Used with the angle brackets on an MDF false wall; without the angle brackets on a tank stand |
MVHR-DRAIN | Condensate drain take-off recommended as the primary condensate connection | Uninsulated drain pipe with minimum 5° fall to the soil and vent pipe |
PVC604 | Louvre grille for 150 mm ducting, shown for intake and exhaust in the AB-WH1 ducting arrangement | |
PVC501 | Air brick for 204 x 60 mm rectangular ducting, shown for intake and exhaust in the AB-WH1 ducting arrangement | |
VS150 | Ceiling air valve for 150 mm ducting, shown for supply and extract in the AB-WH1 ducting arrangement | |
VS125 | Ceiling air valve shown for supply and extract in the AB-WH1 rectangular ducting arrangement |
Maintenance schedule
| Task | How often |
|---|---|
| Inspect the filters Two G3 filters accessed from the front panel | After 6 months |
| Replace the filters Depending on the environment, filters may be cleaned with a vacuum cleaner or replaced | Every 12 to 18 months |
| Professional inspection of the unit Includes the filters, heat exchanger and motors | Annually |
| Inspect the heat exchanger Check generally for damage and security of components, then refit the cover | Every 5 years |
Performance & technical data
Extract ventilation rates by room (ADF 2010)
| Room | Minimum high rate |
|---|---|
| Kitchen | 13 l/s |
| Utility room | 8 l/s |
| Bathroom | 8 l/s |
| Sanitary accommodation | 6 l/s |
Minimum low rate: total extract rate should be at least the whole dwelling ventilation rate given in the next table.
Whole dwelling ventilation rates
| Number of bedrooms | Whole dwelling ventilation rate |
|---|---|
| 1 | 13 l/s |
| 2 | 17 l/s |
| 3 | 21 l/s |
| 4 | 25 l/s |
| 5 | 29 l/s |
The minimum ventilation rate should also be not less than 0.3 l/s per m² of internal floor area, counting all floors. Based on two occupants in the main bedroom and one in each other bedroom; add 4 l/s per occupant for higher occupancy.
WH1 range versions
| Model | Handing | Bypass |
|---|---|---|
| MRXBOX95-WH1 | Standard | Non-AB (thermal bypass behaviour) |
| MRXBOX95-WH1-OH | Opposite hand | Non-AB (thermal bypass behaviour) |
| MRXBOX95AB-WH1 | Standard | Integral automatic HX bypass |
| MRXBOX95AB-WH1-OH | Opposite hand | Integral automatic HX bypass |
Accessories & controls
SIL-WH1 silencer
- Part number SIL-WH1
- Four airflow chambers
- Wall mounting bracket supplied
- Sits on top of the unit and clamps in place with toggle clamps and safety pins
- Minimum 75 mm advised either side of the unit for clamp access
FF-WH1 first fix plenum chamber
- Part number FF-WH1
- Four 204 x 60 mm rectangular spigots, two each side
- Four hanging brackets fixed to the underside of the floor slab at first fix
- 30 mm clearance between the wall and the rear face of the plenum
AV-WH1 anti-vibration tray assembly
- Part number AV-WH1
- For loft space mounting
- Used with angle brackets on an MDF false wall across the roof trusses, or without them on a tank stand
MVHR-DRAIN condensate take-off
- Part number MVHR-DRAIN
- Recommended primary condensate take-off
- Minimum 5° fall to the soil and vent pipe
- Fit before any T piece connecting to a CONTRAP drain
Speed 3 switch
- Optional switch that overrides speed 1 and speed 2 to run the fans at maximum airflow
- Wired through the kitchen or light switch arrangement shown in the wiring diagrams
Ecosmart sensors and MRXBOX-JB junction box
- Part number MRXBOX-JB
- Connector for Ecosmart devices on the base of the unit, next to the cable entry
- Junction box needed where more than one Ecosmart sensor is used
- Installation instructions in leaflet 671700
Remote fail indicator
- Part number MRXBOX95-RFI
- Optional
- Connects to the fail terminals on the unit
Troubleshooting
Supply Fan Fault LED lit
Likely cause: A fault on the supply fan is being indicated on the front panel
What to do: Isolate the unit before any work and have a competent person examine it. Equipment with a suspected failure should be taken out of service until a competent person can repair or examine it.
Extract Fan Fault LED lit
Likely cause: A fault on the extract fan is being indicated on the front panel
What to do: Isolate the unit before any work and have a competent person examine it. Equipment with a suspected failure should be taken out of service until a competent person can repair or examine it.
Filter Change LED lit
Likely cause: The filters are due for attention
What to do: Isolate the unit, then inspect and clean or replace the two G3 filters as described in the filter change steps.
Water overflowing from the internal condensation drip tray
Likely cause: The unit has not been installed true in all three dimensions
What to do: Re-fit the unit so that it is level in all three dimensions, using a competent installer.
Supply fan runs at trickle speed in very hot weather (non-AB models)
Likely cause: Thermal bypass behaviour: the supply fan reduces automatically in excessive outside temperatures to help prevent overheating
What to do: Use additional ventilation measures such as open windows or trickle vents (if fitted).
Fan speed changes briefly
Likely cause: Radio frequency interference
What to do: No action: this is normal and the speed returns to normal once the interference has subsided.
Condensation or mould in the dwelling
Likely cause: Unit switched off, or controls and valves adjusted after commissioning
What to do: Keep the unit switched on at all times and do not adjust the commissioned settings; contact a competent installer if the problem continues.
At a glance
- Unit type
- MVHR
- Manufacturer
- Nuaire
- Product range
- Nuaire WH1 wall mounted range
- Versions
- MRXBOX95-WH1, MRXBOX95-WH1-OH, MRXBOX95AB-WH1, MRXBOX95AB-WH1-OH
- Handing
- Standard and opposite hand (OH)
- Mounting
- Wall mounted on a solid wall, or a stud partition with 25 mm MDF behind the board; loft mounting on an AV-WH1 tray
- Spigots
- 4 x 150 mm diameter, top of unit
- Designed for
- Medium to large new build properties
- Guarantee
- 5 years: parts and labour in year 1, parts only in years 2 to 5
- Up to 95%Heat recovery (manufacturer's stated figure)
- 4 x 150 mmDuct spigots
- 2 x G3Filters fitted (188 x 413 mm)
- 1.3 ACurrent consumption (3 A fuse)
- 623 x 658 x 432 mmHeight x width x depth
- 5 yearsWarranty
Nuaire MRXBOX95-WH1 features
All models
Two independent fans
Separate supply and extract fans each have their own speed control, so background and boost flow can be set for each side of the system during commissioning.
Heat exchanger
The heat exchanger transfers heat from the extract air to the incoming air; the manufacturer states it can recover up to 95% of the heat normally wasted.
Interlocking wall bracket
A two-part bracket is fixed to the wall and to the rear of the unit, and the unit simply interlocks over the wall-mounted part. The unit must be level in all three dimensions to avoid drip tray overflow.
Standard and opposite-hand versions
The OH versions mirror the airflow arrangement of the standard units, so the spigot layout can be matched to the duct runs in the dwelling.
Speed 3 override
An optional speed 3 switch overrides both speed 1 and speed 2 and drives the fans to maximum airflow, for example from a kitchen switch.
Front-access filters
Both G3 filters are removed from the front by pulling off two filter covers, then drawing each filter out by its loop, with no need to take the unit off the wall.
AB models only
Automatic summer bypass
A wax actuator opens the bypass damper automatically so air can pass around the heat exchanger and deliver fresh filtered air in warmer months.
Integral humidity sensor
A sensor in the extract airflow boosts the unit to the commissioned boost speed when humidity exceeds an adjustable set point on the front of the unit. It should not be relied on alone, so a switch local to the wet rooms is also used.
Non-AB models only
Thermal bypass behaviour
In excessive outside temperatures the supply fan reduces automatically to a trickle speed to help prevent overheating, so additional ventilation such as open windows or trickle vents may be needed.
Installing the Nuaire MRXBOX95-WH1
The unit is installed indoors on a solid wall, away from direct sources of frost, heat, water spray or moisture generation, using the supplied interlocking bracket; a gypsum block or ordinary stud wall is not sufficient unless a 25 mm minimum MDF panel is solidly fixed behind the board, extending over at least three studs at no more than 400 mm centres and ideally from floor to ceiling (minimum 2 m). Allow at least 430 mm clear space in front of the MRXBOX95-WH1 for cover removal and filter changes, and install the unit level in all three dimensions.
Use rigid 150 mm circular or 204 x 60 mm rectangular ducting where possible, insulate the intake and exhaust ducts, keep intake terminals at least 300 mm from a gas boiler balanced flue as a guide, and pipe the condensate through a filled U-trap or equivalent airlock. Remove the protective film from the filters before commissioning, and commission with a calibrated moving vane anemometer and hood.
Installation must be carried out by competent personnel, and the electrical connection by a qualified electrician. Isolate the unit, switched live and Nuaire control from the mains before any work.
