Replacement Solar Powered Vent Opener Cylinders

Replacement Solar Powered Vent Opener Cylinders

Replacement cylinders for Bayliss Automatic Vent Openers and other brands


Looking to replace the cylinders in your Automatic Vent Openers (AVO)? If you’ve noticed that your AVO’s are not functioning correctly, it’s likely time for a replacement cylinder. Please note that this listing is for replacement AVO cylinders only.

For complete Automatic Ven Openers please view this listing.


MK7 Triple Spring Automatic Vent Opener

Our standard automatic vent opener for BC Greenhouses. The perfect option for your roof vent openers or double side vents. With three springs to help pull the vents shut and deal off your greenhouse. Sold in packs of 2.

Opening Range

55F (13C) to 70F (21C)

Super Heavy Automatic Vent Opener

Our Super Heavy AVO is designed specifically for double glass roof vents and can handle up to 35 lbs. of attached weight. Sold Individually.

Opening Range

60 F (16C) – 75F (24C)

Orchid Wax Automatic Vent Opener

The Orchid Wax AVO is the perfect vent opener for your hothouse environment, allowing your greenhouse to warm up a little more than our other options before engaging the vents. Sold in packs of 2.

Opening Range

70F (21C) – 85F (30C)

MK3 Automatic Vent Opener – Old Style

The MK3 unit was made during the 1970s and early 80s from cast aluminum and was colored silver, green, and sometimes orange

Only sold in packs of 2.

Check out our BCG Roof Vent Cylinder Brochure or watch our video below for instructions on how to replace your cylinder.


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