Servicing, genuine filters and repairs for every Nuaire MRXBOX unit, from older MRXBOX95 models to the latest ECO range. Full service from £149, across Bristol, Bath and the South West.
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NUAIRE MRXBOX
MRXBOX is Nuaire’s range of MVHR units. They’re fitted in a lot of new-build homes and apartments, usually in a cupboard, loft or ceiling void. The unit pulls stale, moist air out of kitchens and bathrooms, recovers heat from it, and supplies filtered fresh air to living rooms and bedrooms.
We service and repair every model, including the MRXBOX95 range (such as the WH1, WM1 and LP1) and the MRXBOXAB-ECO range (such as the ECO2B, ECO3 and ECO4). Not sure which you have? The model is printed on the label on the unit.
Newer MRXBOX units, such as the ECO range, have a row of indicator lights. Here’s what each one means, based on Nuaire’s installation manual. Layouts differ between models, so check your own manual too.
Your filters are due. Nuaire says to replace them every 12 months. The light turns itself off after 5 days, so don’t ignore it.
The fan that brings fresh air in has a problem, often a worn or failed motor. The unit won’t ventilate properly until it’s fixed.
The fan that removes moist air has a problem. Expect condensation and lingering steam until it’s repaired.
The summer bypass is open, letting fresh air skip the heat exchanger to help keep your home cool. Normal, not a fault.
The unit is protecting its heat exchanger in very cold weather. Normal in winter. If it stays on in mild weather, get it checked.
Show which fan speed the unit is running at. Speed 3 is the highest, used for boost, for example when a bathroom humidity sensor kicks in.
Source: Nuaire installation manual for the MRXBOXAB-ECO2B (document 671986). View the manual (PDF)
What Nuaire’s own manuals recommend, and what we cover at every service.
Clogged filters or an unbalanced system, usually from missed services.
Same fixed prices for every make, confirmed before we arrive.
£149
Deep clean, new filters, airflow tested and rebalanced in every room, photo report. 90–120 min.
£80
Full diagnosis, duct and airflow checks, PCB testing, written repair quote.
From £1,290
Supply and fit, controls set up, airflow set, hand-over demonstration.
Nuaire publishes installation manuals and user guides for its MRXBOX units:
Can’t find the manual for your model? Send us the model from the label on your unit and we’ll help.
What customers say after a Ventfix visit.
We service all makes and models, including
Your filters are due for changing. Nuaire’s manual for the ECO range says to replace filters every 12 months. The light switches itself off after five days, so don’t take that as a sign the filters are fine.
The unit has detected a problem with that fan, often a worn or failed motor, or an electrical fault. Book a fault-finding visit so the cause can be confirmed and fixed.
The summer bypass is open, letting fresh air in without passing through the heat exchanger to help keep your home cooler. It’s normal and not a fault.
Nuaire recommends inspecting the filters every 6 months and replacing them every 12 months, with an annual professional inspection. We service MRXBOX units once a year.
Nuaire says only genuine Nuaire parts and filters should be used, and that not maintaining the unit as recommended can invalidate the warranty. We fit the correct filters for your model.
Yes. We fit like-for-like or improved replacement units, from £1,290 supplied and fitted.
Usually 90 to 120 minutes, depending on the size of the system.
Ventfix is an independent MVHR specialist and is not affiliated with or endorsed by Nuaire. Brand names are trademarks of their respective owners.
Fixed price, genuine filters, photo report after every visit.
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