VAV box throttling range

[ickabod]

In a pneumatic VAV with a spring range of 8-13# and elec heat set at 13#, What should the output pressure of the t-stat be at room temperature? Thanks.

 

[stanlsimon]

there are some variables that need to be known in order to answer. Single pipe Air to tstat or two pipe, reverse or direct acting actuator, is the electric heat modulating or on/off. There should be a control drawing from Honeywell or Powers or whoever did the installation which would give the information you need.

 

[ickabod]

Two pipe reverse acting t-stat. Electric reheat on @ 13psi pressure independant normally open VAV. Damper actuator has a spring range of 8-13psi. Should the t-stat be calibrated for mid-spring range or the middle of control span 3-15psi?