Exhaust air heat pumps (EAH) combine ventilation, heating & hot water as an all-in-one energy efficient solution. They extract warmth from indoor stale air, which is typically expelled from bathrooms, kitchens and utilities and uses this to pre-heat the warm supply air that is supplied into the dwelling via ducts for radiator or underfloor heating as well as domestic hot water for showers.

By using this renewable energy source to pre-heat the supply air, we can dramatically reduce energy demand and in turn minimise carbon emissions. In addition to this, the system has additional benefits such as contributing towards compliance with building regulation requirements for continuous ventilation of buildings, reducing energy costs and helping to maintain healthy indoor environments.

The system works by capturing energy from the warm exhaust air, which is typically expelled through a mechanical ventilation heat recovery system, and then transferring this into the hot water cylinder. This enables the system to provide heating as well as ventilation and it can be installed into new build houses, apartments or refurbished dwellings.

This system is often used in conjunction with a biomass boiler to provide back-up heating during periods of low demand or when the hot water consumption is highest. This is also a very popular system for new builds, as it is an effective way to meet Code For Sustainable Homes heating & ventilation targets, whilst providing a cost effective energy solution for heating & hot water.

There are a number of options available for an EAH, including micro heat pumps which have been around for a while now and are commonly found integrated into the top section of the hot water cylinder. This is the most common type of system and is an effective means of meeting your energy requirements if you are only using it for space heating.

A more recent development is the NIBE exhaust air heat pump which does not need a separate fan and instead takes the pre-heated stale air from the bathrooms, utilities and kitchens, pumps it through the heat pump to extract energy and then blows this into the dwelling through a duct. This is a much more efficient system and it can save you even more Kwh's per year.

Exhaust air heat pumps can be installed into existing properties, but it is very important that they are properly specified, designed, installed and commissioned to ensure the best possible performance. Incorrectly sized or configured systems are likely to consume more energy than they should, leading to increased running costs and reduced efficiency.

NIBE offer a range of exhaust air heat pumps with different rated in-built immersion heaters to accommodate differing heating demands and property sizes. For example, the NIBE 200P has an in-built immersion heater rated at 3Kw, and the 410P has an in-built heater rated at 8Kw.

Typical installation of an exhaust air heat pump system into a new build house or apartment will cost approximately PS9,000, including all the ductwork at 1st fix stage and electrics for the system. This includes commissioning and ensuring the system is compatible with your existing hot water cylinder.