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Separate ERV intake and exhaust or tandem?

Jeremy Turner | Posted in General Questions on

We are installing an ERV in a new house and the hvac contractor has suggested using a tandem intake/ exhaust vent that looks like the attached sketch. The ERV installation manual allows this as well as two separate vents with a minimum of 6 ft between them.

These will be installed about 12 feet above ground level. It looks like there is a possibility of cross contamination with the tandem unit. Should I ask for two separate vents?

Any advice will be appreciated.

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  1. GBA Editor
    Martin Holladay | | #1

    The unit in the illustration is designed to minimize cross-contamination of the air streams, and it will work.

    However, this type of fitting is designed for homes where it's impossible to have two separate penetrations (one for fresh air intake, and one for exhaust). If you can accommodate two separate penetrations, that approach is always preferable.

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