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VAV works like CAV?

asked 2016-04-13 10:02:46 -0500

Peter Horvath's avatar

updated 2016-04-13 11:03:40 -0500

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?

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answered 2016-04-13 11:23:46 -0500

lutinfr's avatar

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.

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Thank you for your response, but i'm using e+ under DesignBuilder platform - sorry for not informing you.

Peter Horvath's avatar Peter Horvath  ( 2016-04-27 09:25:58 -0500 )edit

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Asked: 2016-04-13 10:02:46 -0500

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Last updated: Apr 13 '16