Make Up Air System (MAS)

Efforts to make your home more energy efficient prevents fresh air from entering the home and can lead to compromised air quality and appliance inefficiency. Weather stripping, caulk, sealants, and moisture barriers such as Tyvek® tighten the home, reducing air changes can lock stale air inside. Exhaust ventilation like bathroom fans and exhausting appliances like clothes dryers, range hood fans, and gas fireplaces can create negative pressure causing heating appliances take more time to do their jobs and wasting energy.

These problems can be solved with the installation of a Make-Up Air System (MAS). The MAS delivers fresh air automatically, improving indoor air quality, improving appliance efficiency, and saving energy. Meets or exceeds ventilation standard ASHRAE 62.2.

Exhaust ventilation systems remove air from a particular location, often leading to depressurization in the home. Replacement or make-up air will infiltrate through leaks in the building shell and other uncontrolled sources. A make-up air damper can be added to the central system when exhaust ventilation is employed. The MAS provides replacement air as needed from a controlled source into the return air plenum where it is tempered and distributed throughout the home. Makeup Air Systems consist of a make-up air damper, mounted on the return air duct of an HVAC system, and an intake air hood, installed through an exterior wall, to allow outdoor air into the home, with the two being typically connected by installer-supplied standard 6″ galvanized sheet-metal pipe. Functions with or without the HHSC+ control.

How it Works

The system connects the HVAC system to the outside to allow controlled amounts of fresh air to enter the system when needed. The system automatically senses pressure changes and a need for air flow and opens to bring a precise, metered amount of fresh air into the air handler. Here the cold air is tempered as it mixes with warm air in the return duct. The air is then heated and distributed through the home via the central duct system. When the need for air is fulfilled, the system closes to prevent further air infiltration. The system must be installed by a qualified heating and air conditioning professional and is adjustable for homes from 1000 to 4000 square feet. It does not require any electricity or maintenance.

The MAS-1 and MAS-2 should be installed by a licensed contractor. Find a contractor in your area.