Unmet Hours

VAV works like CAV?

I'm trying to simulate an AHU, which modulates its fan speed due to the sensible heat gains from the zones. The AHU should use its own heating and cooling coil without any reheat in the zone (there is no other HVAC equipment there, like FanCoils or radiators)

As far as i know, for this purpose i should use VAV instead of CAV, but when check the fan's Mass Flow Rate it's linear - not modulating at all...

Am I understanding wrongly these systems?

Fan should have flow control to manage how it’ll function, but current Openstudio does not provide enough flow control. You can try “Warmest Zone Supply Temp and Flow Reset” and set Strategy: FlowFirst – This is only flow control that I see in OS. Temperature control can be placed to other node.

image description