PO-86-01-4 -- VAV System Volume Control Using Electronic Strategies

Air volume can be measured reliably with conventional electronic differential temperature techniques. Controlling the actual outside-air minimum volume independent of the variable supply fan delivery is necessary to meet minimum ventilation and positive building pressurization requirements. Simulated exhaust-fan flow signals can be added electronically and subtracted from return-fan and outdoor-air make-up volumes to balance the airflow requirements for buildings, maintaining a desired space static pressure. Energy can be saved by admitting only the required outside-air volume and by controlling the return-air volume for variable exhaust requirements, resulting in lower return-fan brake horsepower. This paper discusses control techniques applied to systems installed in the Utah area during 1984 and 1985.

Units: Dual