Zehnder HRV Installation Issues
We have a Zehnder ComfoAir 350 installed in our pretty good house. The unit itself is great, but a few mistakes were made during installation. One of them has been bothering me since installation in 2016.
The drywall around the 125mm steel duct for the return diffuser (Zehnder UK calls them “extract valves”) were cut too large and the resulting hole was not able to be covered by the return diffuser. This diffuser is a combination adjustment for the return air flow and a trim piece to cap the steel duct. It is the portion that you see on the ceiling. To remedy this, the installer glued on a wide plastic flange from a ceiling can light onto the return diffuser. They did an okay job of it, but it doesn’t match perfectly. The other issue, which is a Zehnder issue, is that when you use the Zehnder return diffuser filter, it covers the rubber seal, which doesn’t allow the diffuser to grip onto the steel tube very well and therefore it doesn’t sit flush against the ceiling, it leaves a gap.
Wondering if anyone has had these issues and what they did to remedy them or am I the lucky one?
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