When can I start up my new Zehnder ventilation unit?


In a modern home, the balanced ventilation unit (HRV or ERV) is like the lungs of the building, optimizing air exchange for a healthy environment. Like human lungs, your ventilation unit is connected to the environment through passageways that need to be kept clean. The system won’t operate correctly when the valves, ducts and heat exchanger are clogged with dust, dirt, and construction debris. 

If you decide to power up your Zehnder unit before construction is completed (and/or before filters are installed) you will likely introduce a load of dust to your air distribution system that will be very difficult to clean out. You may even damage some components of the system.

These pictures show a construction project that is nearing completion, but clearly isn’t finished. The ventilation system was started too early and the result is a huge amount of dust caking the extract air filters. Once filters become this dirty, air pressure builds up and likely forces dust further into the duct system.

Follow the checklist below, taken from our General Installation Manual, for the critical pre-start-up steps that ensure your filters won’t start and end their lives this quickly!

BEFORE plugging in your unit: 

  • Be sure construction is complete and all spaces have been cleaned of major dust.
  • Be sure the filters are installed in the unit, and the proper filters on the proper side (G4 on interior side and F7 on exterior side)
  • Be sure the filters are installed in all return diffusers.
  • Be sure all adjustable diffusers are fully open.
  • Be sure exterior grilles are installed and not obstructed.

Only then are you ready to start your system. Our manuals include further information about how to activate your Zehnder ventilation system. More questions regarding start up? Contact us at info@zehnderamerica.com or 603-601-8544.