Quark and Louball, thanks for the posts. The issue has been resolved by changing all 4 fan motors in "A" to 3/4 hp motors, allowing a change in drive pullies from 3" to 3 1/2" (per fan mfr. recommendations.) The resulting increase in fan RPM boosted each fan's performance...
I work at a research facility which uses several greenhouse facilities. There are two greenhouses side by side with nearly identical volumes. One ("A") is a gabled design and the other ("B") a semi-quonset (curved roof) design. Both are 30ft. in width and 100ft. in length...
