Knowledge centre
Frequently asked questions
Clear answers to common ventilation questions.
What is an MVHR system?
MVHR supplies filtered fresh air to living spaces while extracting stale, humid air from wet rooms. A heat exchanger transfers much of the heat between the two air streams.
How often should MVHR filters be changed?
The correct interval depends on the unit, filter grade, location and household conditions. Filters should be checked regularly and replaced according to the manufacturer’s guidance or when visibly loaded.
Why is my MVHR system noisy?
Noise may be caused by dirty filters, incorrect fan settings, restricted ductwork, loose components, poor valve adjustment or an ageing fan motor.
What is the difference between MVHR and MEV?
MVHR supplies and extracts air while recovering heat. MEV continuously extracts air from wet rooms and relies on replacement air entering through designed inlets.
What does a PIV unit do?
PIV introduces filtered air into the property, helping dilute humidity and stale air. It is often considered where condensation and mould are concerns.
Why is ventilation commissioning important?
Commissioning measures and balances airflow so the system operates according to its intended design rather than relying on guesswork.
Do ventilation systems need maintenance?
Yes. Filters, fans, heat exchangers, valves and controls need periodic checks and cleaning to support reliable performance.
Can you service landlord and developer properties?
Yes. We work with homeowners, landlords, builders and developers, including planned maintenance and multi-property support.