JOB REF: Client: HVAC Pressurisation Calculator Length Width Height What is the size of the "room" to be pressuri 4 m 2.5 m 3 What is the pressure we require in the "room" 50 PA How many air changes do we require? 12 Per Hour Vent Size? 200 mm 200 mm How Many Vents? 2 QTY Q = 2610 x A x (DP)1/2 (Q is "Leakage" Rate) Source: ASHRAE 1999 Applications We need to deliver 106.1251 Litres per second to maintain a pressure of 50 PA in the "room" with the vents specified This equates to 12.74 Air Changes Acceptable? NO! YES! Additional Info Calc If the HVAC supplier supplies 135 L/sec The pressure in the house will be 63.60416 PA given the dims of the hous 12 Air Changes Per Hour Requi 100 L/Sec throughput
