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Bayliss MK 7 Hydraulicheck Vent Opener

An extremely reliable automatic vent opener with unique features.
The Bayliss Hydraulicheck Vent Opener has a small hydraulic damper which causes the vent to open slowly but to close very quickly making the opener suitable for use on greenhouse roof vents in exposed areas, the unique damper will prevent the vent from being wrenched open in high winds and subsequently damaged.


£68.95
SKU VEMK7H
For roof or side windows in severely exposed positions 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!).

Satin anodised aluminium unit approx. 11˝" (29cm) long which exerts a load of 13lbs (6kg) i.e. it will lift a vent weighing up to 26lbs (12kg).

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

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.

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

Supplied complete with comprehensive installation instructions.

Learn more
To avoid excessive temperatures it's important to have an adequate number of vents in the greenhouse. Ideally the vent area should be a fifth of the floor area - a combination of roof and side vents will improve airflow.


To Learn More About How Automatic Vent Openers Work Click Here

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