Last reviewed: by the MVHR Expert engineering team
Our MVHR service restores the system to its designed performance. We don't just swap a filter and leave — we measure airflow at every valve, compare it with the design rates, and give you a written record of what we found.
What's included in every MVHR service
- Inspection and replacement of supply and extract filters
- Heat exchanger (core) removal, inspection and clean
- Fan and impeller clean and bearing/noise check
- Condensate drain and trap check, cleared and refilled
- Valve, grille and accessible ductwork inspection
- Airflow measurement at valves against the design rates
- Summer bypass, boost mode and control/sensor test
- Written service report with photos and recommendations
Signs your MVHR is overdue a service
- Condensation on windows or damp, musty smells
- Black mould starting in bathrooms or bedrooms
- Weak airflow from supply or extract valves
- Louder humming, whistling or rattling from the unit
- A filter warning light or fault code on the controller
- Rooms feeling stuffy, or higher energy bills than expected
How it works
- Book. Call or send the enquiry form. Tell us the make/model if you know it — a photo of the unit label is plenty.
- Arrive with filters. We carry common filter sizes for most major brands, so most services finish in a single visit.
- Service & measure. Clean, replace, reseal and test. Airflow is measured at every valve and compared with the design figures.
- Report. You receive a written report with before/after readings and any recommended follow-up work.
How often does an MVHR system need servicing?
Most manufacturers specify an annual service, with filters inspected or replaced every 6 to 12 months. In London — especially near main roads, construction or in ground-floor flats — filters clog faster, and six-monthly changes are common.
Skipping servicing doesn't usually cause a sudden failure; it causes a slow decline. Airflow falls, moisture is no longer cleared, and the first sign is often mould or condensation rather than a fault light.
Why a proper service is more than a filter change
Filters are only one part of the picture. Dust bypasses clogged filters and coats the heat exchanger, restricting airflow and cutting heat recovery. Grease and fluff build up on fan impellers, causing imbalance and noise. A blocked condensate trap can leak into the ceiling or cupboard below.
Airflow measurement is the part most quick services skip — and the part that tells you whether the system is actually ventilating the home as designed.
MVHR servicing for landlords, managing agents and blocks
We run block-wide MVHR servicing programmes for property managers, housing associations and developers: coordinated resident access, per-unit records and pricing to be discussed for your block or portfolio. Servicing records also help demonstrate that ventilation is being maintained, which supports Building Regulations Part F compliance and warranty conditions.