Heat recovery ventilators

What a wall heat recovery ventilator is

A small fan with a ceramic or enthalpy heat exchanger in a tube through the outer wall. It alternately supplies fresh outdoor air and extracts stale air. Heat from the outgoing air stays in the exchanger and warms the incoming air, so the room does not cool down in winter and windows can stay closed.

When you need one

• PVC windows are closed, the room is stuffy and by morning the air is heavy with CO₂.
• Condensation or mould on windows and in corners — the unit removes excess moisture.
• A bedroom or nursery faces a noisy street and you want ventilation without the noise.

How to choose

Look at airflow (m³/h) and room size. A typical bedroom needs 25–70 m³/h. Single-tube units work best in pairs: one supplies while the other extracts. The Hoshi HS-HRV1.5WKEC is a two-duct supply-and-exhaust unit with multi-stage filtration for larger flats.

Installation

It needs a through-hole in the outer wall and a socket or power supply nearby. Selection, supply and installation on request: message or call us, the installer checks the wall and quotes before work starts.