Does the vent have to be installed by a professional for the warranty?

Yes. Under Duco's warranty terms, the warranty lapses if the vent is not installed by a recognised installer.

The installer fills in the warranty card on the day of installation, or you keep an invoice showing the installation date. If you install the vent yourself, you cannot claim Duco's warranty in case of a defect. We supply the vent made to measure; you install it yourself or have a professional do it.