I'm modeling a building with multiple zones per floor. Each floor is
supplied by two identical air handlers supplying 26,000 cfm each. I
would like to model it as a single system. Should I:
1. Model a single AHU with 26,000 cfm and assign it a multiplier
of 2 (system sizing ratio)
2. Model a single AHU with 52,000 cfm without the sizing ratio
(sizing ratio 1).
3. Model both air handlers (would prefer not to).
Vikram Sami, LEED AP
Vikram,
When you use a sizing ratio of 2, you're oversizing the system by 100%
while the loads stay at 1/2 of what they should be. This is not what you
want.
Depending on the system type, using a single unit with 52,000 cfm can
affect the results because of the different load diversity.
Kamel Haddad