The passive house building standard is becoming increasingly popular these days, and for good reason. This highly-efficient standard helps to create an indoor space that boasts exceptional comfort and acoustic isolation. It also enables a building to remain environmentally friendly through its efficient energy usage, as well as aiding the affordability of many homes. By simply scratching the surface, it’s easy to see why it’s one of the world’s leading energy efficiency standards. 

With the rise in popularity of passive house applications, many manufacturers have worked meticulously to further the development of passive house technologies. Zehnder are one such manufacturer who have helped to increase the efficiency and performance of said technologiesAnd this month, we’re going to take a look at the brand new Zehnder ComfoPost Air to Water Heat Exchanger… 

Efficient And Effective Heat Exchanger Solution 

Zehnder are renowned for their quality designs and creations, and the ComfoPost range is no exception. This series of air to water heat exchangers has been designed for use with Zehnder’s ComfoWell air distribution connections, providing a seamless fit with exceptional compatibility. 

With ComfoWell connections, each ComfoPost model provides excellent selection flexibility, enabling the attachment of either rigid circular ductwork or Zehnder’s high-quality ComfoTube semi-rigid ductwork. This ensures excellent versatility during installation and use. 

Robust Construction 

That revered Zehnder quality is evident in the construction of each and every ComfoPost model. On top of their versatile design, each model in the range is crafted from durable galvanised steel, whilst aluminium fins and copper piping forms the heating and cooling coils. This rugged construction also features hydrophilic treatment for further enhance the unit’s thermal transfer properties. One of the biggest benefits to the ComfoPost range’s construction is the maintenance-free design, meaning the system can continue to run smoothly with ease. 

The models also feature options to combine attenuators, a manifold box, a filter housing (with ISO ePM1 >80% (F7), ISO ePM1 >90% (F9)) or active carbon filters and end plates with diameters ranging from 125mm to 200mm. You can mount any of the models within the ComfoPost range both horizontally or vertically. 

Four Models For Every Application 

Designed for seamless use with Zehnder’s ComfoAir units, the ComfoPost range consists of four models to suit different airflow requirements up to a maximum of 166l/s (600m³/hr): 

  • Zehnder ComfoPost CW6 – Suitable for airflows of up to 83.3l/s (300m³/hr) 
  • Zehnder ComfoPost CW8 – Suitable for airflow of up to 111.1l/s (400m³/hr) 
  • Zehnder ComfoPost CW10 – Suitable for airflow of up to 138.9l/s (500m³/hr) 
  • Zehnder ComfoPost CW12 – Suitable for airflow of up to 166l/s (600m³/hr) 

What’s more, regardless of the model required, Zehnder have designed each and every one of them to be suitable for Passive House applications. 

Key Features And Benefits 

Here’s a breakdown of the main features and benefits of the Zehnder ComfoPost range: 

  • Ideal for use with reversible heat pumps or chillers to meet SAP 10 or TM59 overheating demands 
  • Low pressure losses 
  • Filtered fresh supply air, not recycled stale air 
  • Suitable for use with the unique modular ComfoWell manifolds 
  • Suitable for horizontal or vertical installation 
  • Condensation water tray and drain as standard 
  • Suitable for Passive House application 
  • Corrosion resistant 


If you’d like anymore information on the ComfoPost series or any product from Zehnder or the rest of our manufacturers, get in touch with us today. You can contact us via our online form, send an email to or give us a call on 0121 351 5604. No matter how you get in touch, a friendly member of our knowledgeable team will be on hand to answer your questions and find the best solution for you and your needs.