Changing System fromVAV System w/ Reheat to CAV w/ No Reheat

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I am attempting to change my VAV system w/ reheat to a CAV system w/ no
reheat. I believe I have accomplished the change to constant volume by
changing the 'fan control' of the AHU to 'constant volume'. How do I remove
any reheating from the previous VAV system? Do I change the reheat delta T
to zero?


Robert Des Rosiers, LEED-AP

Robert Des Rosiers's picture
Joined: 2011-09-30
Reputation: 0


1. Go to Fans/Flow Parameters/Set 'Min Flow Ratio' to 1. This will make sure that the air volume does not vary.

2. Go the the Heating tab under Coil Cap / Control, set the Zone Heat Source to 'Not Installed' then right click on Reheat Delta T and select Restore Default. That'll make the Reheat Delta T option grayed out. Now specify the Hot Deck Max Leaving Temp-- can be the same as Zone Entering Max. Supply Temp., it is the maximum temperature of air leaving the heating coils.

3. The other option would be to change the system type to Reheat Fan System and don't specify any reheat-as per 2 above.

Hope it helps.

Best regards,

Gaurav Mehta

Gaurav Mehta2's picture
Joined: 2011-09-30
Reputation: 0