Makeup air units, sometimes called MUA systems, bring in outdoor air to replace air that no longer circulates or ventilates out of the building. The unit pulls in fresh air and, depending on your unit, may heat or cool it. This allows the make-up air unit to supply temperate fresh air into the building. This replacement air can help improve negative pressure and indoor air quality.
These units often see use as industrial make up air systems but they work well in a variety of areas. You can find them in industrial applications, restaurants, residential buildings, and more. According to Stelpro, their MUAA series units meet ANSI/UL 1995 and ASHRAE 62.2 ventilation and acceptable indoor air quality (IAQ) requirements for low-rise residential buildings.
As a compact unit, Stelpro's MUAA series offers multiple installation positions including horizontal, vertical, and up or down. The horizontal air flow works for all models while vertical air upflow or downflow works for 6-inch to 10-inch models. They contain an integrated temperature sensor as well as continuously modulating heating elements to heat fresh air.
They offer these additional features:
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