MultiFamily Equipment Room

Today’s multi-family projects can be a real challenge from an HVAC standpoint. Smaller apartments, especially those located on the North side of the building, have a small cooling load, sometimes as little as 0.6 to 0.8 tons. We all know that oversizing air conditioning units is bad for humidity control, but manufacturers are simply not designing and manufacturing units that are small enough to serve today’s energy code driven buildings. Don’t even get us started on variable refrigerant (VRF) technology; it is simply not designed for multi-family projects in America.

One component of multi-family design that many do not understand is the airtightness of a modern-day, single apartment – they do not significantly leak or infiltrate airflow. For those interested in calculations, building codes define the permeability (leakage rate) of walls, etc., and these values are often confirmed by blower door tests in the field.

As a result, introducing fresh air into the space is of utmost importance, especially in a pandemic minded environment. Unfortunately, we are not seeing many multi-family projects that properly address the need for outside air. Complicating this is the refusal of local building officials to understand, recognize, or enforce fresh air requirements. Some are predicting legal risks for Owners and citing initial examples of such litigation.

Unfortunately, the introduction of outside air into a small split system unit can be problematic, as oversized equipment cannot run long enough to effectively dehumidify the fresh air that is being supplied. Choosing between mold or virus transmission is not a great choice!

Applied Engineering is proud to provide a fully code-compliant ventilation solution that does address dehumidification. It all fits in a modest-sized closet with ample, yet minimal, room for maintenance and electrical clearance.