AHU Outside Air getting sucked in
AHU Outside Air getting sucked in
(OP)
Hello,
While the OA damper is closed, outside air is getting sucked into the AHU
Return fan is controlled by CFM offset method and the return air damper is controlled inversely to OA and EA dampers.
There is a building static pressure sensor that controls the EA damper.
I'm not sure what else to check so any help will be appreciated.
Thanks in advance,
Hoons
While the OA damper is closed, outside air is getting sucked into the AHU
Return fan is controlled by CFM offset method and the return air damper is controlled inversely to OA and EA dampers.
There is a building static pressure sensor that controls the EA damper.
I'm not sure what else to check so any help will be appreciated.
Thanks in advance,
Hoons





RE: AHU Outside Air getting sucked in
i truly dislike to list number of possible scenarios until you give us more data.
RE: AHU Outside Air getting sucked in
RE: AHU Outside Air getting sucked in
Is your unit leaking and the supply fan pulling from the unit cracks?
Has the AHU dampers been commissioned? Just becasue your drawings say the dampers should be controlled that way, doesnt meen they are.
knowledge is power
RE: AHU Outside Air getting sucked in
System has not been commissioned yet.
RE: AHU Outside Air getting sucked in
Is the return air ducted to the AHU or is it free return into the AHU room ?
HVAC68
RE: AHU Outside Air getting sucked in
What the problem if you get more fresh air?
RE: AHU Outside Air getting sucked in
the easiest way to verify it, rather than making complex measurements and interpretations, would be to remove exhaust air non-return damper. than, if you notice that air is sucked backwards through exhaust air duct, you know that task is to be delegated to control guy.
RE: AHU Outside Air getting sucked in
Dampers leak a bit if they are not Class 1A, it may also not be closed properly.
RE: AHU Outside Air getting sucked in
RE: AHU Outside Air getting sucked in
JMHO Bro.