Cleaning Exterior Supply Air Grilles for Zehnder Systems

Recently our Zehnder Commissioning Agent Steve Lamberg reported an issue at some of his customer maintenance calls:  Zehnder units not getting any supply air because the exterior ports were clogged.  Dust builds up on the metal grill, then there is some moisture, and the result is a paste that prevents supply air from getting in. 

While this may not be an issue for some of our customers, we wanted to ensure that all Zehnder owners are aware of this maintenance step and check their outside ports, especially the supply ports, as part of their usual seasonal maintenance.  If you check your exterior ports and they are dirty or clogged, here is what to do.    

Cleaning Your Exterior Supply Grills

If you determine that you need to clean your exterior supply grills, it’s important that you turn your Zehnder system off or to away mode before you begin the cleaning.  This will keep dirt and other items from going into your system while you’re doing the work.  Once your system is turned off or to away mode, here is the process:

1. Remove the screws at the bottom edge of the louvered grille. Remove grille and clear of any large debris such as leaves.

2. Using a stiff bristled brush, clean off the louvered grille to free any dirt and dust. Keeping this clean will ensure a smooth and unobstructed flow of air.

3. Use the stiff bristle brush to clean off the wire mesh grille. These can become very clogged and significantly reduce performance of the system. Make sure to keep debris from entering the ductwork. Vacuum the area afterwards to get any dirt left behind.

4. Once you are done cleaning the grilles and ensuring no debris is left behind, replace the louvered grille and fasten it by tightening the screws on the bottom edge.

5. Turn your Zehnder system back on.

It’s that simple to clean the exterior grilles of a Zehnder system. Doing this process throughout the year will keep your system running its best and stave off the need for a technician to come check the equipment.

For help with other routine maintenance tasks, check out our free Small Planet University Course on Zehnder System Maintenance.

If you’ve had your Zehnder system for a number of years, you may want to schedule a maintenance with a skilled Small Planet Supply staff service agent, you can start the process by clicking here.