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Bayliss MK 7 Vent Opener

Suitable for use on nearly all greenhouses this Bayliss MK7 is an extremely reliable, British made, automatic vent opener.
The bayliss Mk7 vent opener is operated by a stainless steel cylinder containing a mineral wax which expands with heat; this pushes a piston causing the vent to open. As the temperature falls the wax contracts and a strong stainless steel spring closes the opener.


£39.85
SKU VEMK7
Bayliss guarantee their openers for 2 years but if anything should go wrong after that replacement cylinders are readily available and easy to fit.

For roof vents weighing up to 14lbs, approx.30" x 30" (76cm x 76cm).

Bolts on to aluminium greenhouses (fixings supplied) - for wooden greenhouses it is attached by wood screws (not supplied).

Fitting neatly close to the glass the opener does not protrude into the greenhouse (so you don't bang your head!), as the window opens the auto opener is pulled into the window hole.

Satin anodised aluminium unit approx. 11˝" (29cm) long which will lift a roof vent weighing up to 14lbs (6kg).

Can be set to start opening the vent at any temperature between 12-25ş Centigrade/55-75ş Fahrenheit, and gives a maximum window opening of 12" (30cm).

Supplied complete with comprehensive installation instructions.

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Fixing Tip

When fitting the Autovent within your greenhouse, the correct preparation beforehand makes fixing simple.

Remove the Autovent unit and fixings from its box.

Place the Autovent unit in a cool place for half an hour - a refrigerator is ideal. This allows the wax in the power tube to contract as it cools.

When the Autovent unit is cool, remove from the refrigerator and place the steel piston rod against a hard surface and push it firmly back into the tube.

The Autovent is not ready to fix in place.


Click Here to see full and comprehensive fitting instructions for this Bayliss Vent Opener.