John Suppes from Clarum Homes explains the Zehnder Heat Recovery Ventilator System at the Menlo Passive Project. One of the keys to a passive home’s efficiency is its air tightness. This means that it’s essential to have a system that brings in fresh air to the house.
All air coming into the house is filtered through a Merv 13 air filter. This means all of the air in the home is clean – free of pollens and particulates. All of the stale air from the home is exhausted through the other side of the HRV. With this system, all the air in the house is exchanged 9 times a day with fresh air. The best thing of all is that this system runs on 16 watts! THe whole house is heated with less energy than a hair dryer.