Marty’s ERV — aka the Energy Recovery Ventilation — watches over the family.  “It’s the intelligent bath fan that brings in fresh air and exhausts the stale air. Our two bathroom units serve the whole house with air quality control. Once I get my final blower door test, we’ll know how much fresh air we need and will set them to run at a certain percentage around the clock. That way it delivers all the fresh air we require for a minimum amount of energy.”