We are remodeling two floors of a high-rise office tower. A 100% OA VAV introduces OA into the mechanical room for each floor where it is mixed with return air. An AHU in each mechanical room distributes the mixed air to the floor using a VAV system.
With this arrangement, I want to confirm that installing an air flow monitor on the two OA VAVs (or simply showing that the fan is "on" per LIR #2099) and installing CO2 sensors in all densely occupied spaces fulfill the monitoring requirements of this credit.
Ante Vulin
Sustainability ManagerYR&G
80 thumbs up
June 3, 2013 - 3:17 pm
The system you describe is not a 100% OA CV system as specified in CIR #2099, so a "fan on" sensor or transducer is not appropriate. For the configuration you describe, the ventilation rate can potentially be determined through monitoring of return, outdoor and mixed air temperatures (before the coil) as well as supply air flow.