Manage the Outdoor Air Moisture Load

Outdoor air represents the largest source of moisture in most buildings. On hot and humid days, Airxchange® energy recovery components dehumidify outdoor air without condensation. On cold and dry days, Airxchange® energy recovery components humidify the outdoor air minimizing the need for additional building humidification.

Combined Systems Can Achieve Humidity Control

An Airxchange® energy recovery component combined with standard HVAC systems is likely to control humidity in even the most humid climates. A Tiax, LLC report provides further details. By avoiding the expense of additional mechanical dehumidification helps pay for the Airxchange® energy recovery component.

Moisture Removal Capacity Comparison

 OA ConditionsOA Moisture LoadDX System (20 Tons DX)DX/ERV System (15 Tons DX, 5 Tons ERV
 95ºDB,78ºWB7.1 gals/hour6.3 gals/hour9.6 gals/hour (4.9 from ERV)
87ºDB,80ºWB10.8 gals/hour7.6 gals/hour13.3 gals/hour (13.3 from ERV)
 75ºDB, 72ºWB 7.2 gals/hour 9.1 gals/hour 11.5 gals/hour (4.7 from ERV)

Calculations assume a 20 ton load with 2000 cfm of outdoor air with indoor design condition of 75/63.. SHR of DX was assumed to be .75 for 95/78 condition, .70 for 87/80 condition, and .65 for 75/72 condition. Airxchange® energy recovery components assumed effectiveness of 70%.

Airxchange® Humidification Examples:

 OA Conditions Moisture Loss Due To Outdoor Air Airxchange® Humidification
 26ºDB, 25ºWB  7.3 gals/hour 5.3 gals/hour
 -4ºDB, -5ºWB  9.8 gals/hour 7.2 gals/hour
 -16ºDB, -17ºWB  10.1 gals/hour  7.5 gals/hour

Calculations assume 2000 cfm of outdoor air with indoor design condition of 72/54. Airxchange® energy recovery components assumed to have effectiveness of 70%