- Joined
- Apr 15, 2023
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- 2,249
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i run passive sshz just with exhaust fan and filter..i also have a box on the in-line side with 3 hepa filters so i need a little more cfm to draw air in.I run the fan on 1/4 to half on controller and takes a 1.30secs to exchange the air on warmer days and bout a minute during winter.so instead of having a lessor smaller cfm fan turned up more making more noise it makes sense to have a bigger exhaust fan.less wear on the fan .

















































