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3509 Bayliss MK7 Hydraulicheck Vent Opener (C3509)



Heavy-Duty Control

The Bayliss Hydraulicheck solar vent opener is the best choice for large roof vents and side-hinged wall vents. A built-in hydraulic damper prevents the vent from being wrenched open by high winds. The damper only allows gradual opening as called for by the solar-powered piston. Two return springs provide positive closing action. Dimensions and lifting capacity are identical to the MK7 standard unit.

About Bayliss Solar-Powered Vent Controls
These "top of the line" solar vent controls will open and close greenhouse vents automatically without electricity. Bayliss vent openers convert energy from the warmth of the sun into mechanical energy to open vents. The hotter it gets, the wider the vents are opened.

Bayliss solar vent openers are made from the best corrosion resistant materials: brass, stainless steel and satin anodized aluminum. They are designed to give many years of service, are covered by a 2-year guarantee and can be repaired should the need arise.

The Standard Bayliss can exert a force of 14 lbs. at the point where it is attached to the vent. A threaded adjuster bolt can set the Bayliss to start opening the vent at temperatures between 55º and 75º F. Maximum opening of 12" is reached at approximately 20º F above the starting temperature.
Openers can be installed in a series on a long vent to replace worn out electric vent motors. The adjuster bolt can equalize the loading so the lifters work in unison.

Easy to install with screws: top arm to vent, bottom arm to greenhouse frame. Illustrated directions included. Standard openers are about 12" long and fit neatly up close to the vent.

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To dis-engage opener:
To disable the the Bayliss opener when needed due to heavy winds or winter weather, simply unscrew the Threaded (knurled) Adjuster, remove it completely and keep the adjuster in a safe place for later use. The vent must be tied securely. You may put a zip-tie around the opener just up from the mounting brackets to lock the vent shut. When ready to engage the vent opener, cut the ties, re-install the Threaded Adjuster. Check to be sure screws are firmly attaching vent opener to the vent frame each season prior to use.

See Also
3510 Bayliss MK7 Replacement Power Tube (C3510 55 75)

Learn More About
3509 Bayliss MK7 Hydraulicheck Vent Opener (C3509)

General Product Information:
Designed for aluminum or timber framed vents measuring up to 2 square feet, lifting a load of up to 14lbs, providing a maximum opening distance of 12 inches and can be set to start opening at approx. 55° F. Supplied with full fixing kit and instructions. The Hydraulicheck is supplied in a satin anodized finish.
The addition of a small hydraulic damper which has been named “Hydraulicheck” to the Mk7 Autovent, offers the best answer yet provided to the problem of wind damage of lightweight vents. It only allows the vent to be opened slowly but it can shut quickly. Whilst the Mk7 Triple Spring model offers an adequate degree of protection in most cases, the Hydraulicheck fitting is advisable in areas where severe conditions are encountered.

Dimensions: 11” x 2-1/2” x 3”
Color: Satin Anodized Finish (silver)

Shipping Information:
Standard shipping charges apply.

The Hydraulicheck is designed to allow the vent to only open slowly but to close quickly. Because the Autovent is normally fitted when the vent is closed, this restriction should present no difficulty.
It is permissible to remove the springs from the unit prior to fitting it to the vent but the springs should be refitted before setting is carried out.
Please remember that the vent can only be opened slowly when a hydraulicheck is fitted so please do not use excessive force when opening the vent by hand prior to fitting the hexagon adjuster.
Apart from this, the Autovent should be fitted and set as per the printed instruction leaflet.

Preparing the unit for fitting:

  1. Remove the Autovent unit and fixings pack from the box.
  2. Place the Autovent unit in a cool place fro half an hour, - a refrigerator is ideal. This will allow the wax in the power tube time to contract as it cools.
  3. When the Autovent unit is cool, remove from the refrigerator and place the steel piston rod (See Fig. 8), against a hard surface and push it firmly back into the tube. The Autovent is now ready to fit.
  4. Because the design of greenhouse vents varies considerably, it is impossible to illustrate every type of fitting. Choose the fitting method most suitable from those shown in the Installation Diagram listed above.
    The Autovent should be fixed as near as possible to the middle of the vent so that it will not twist. See Fig. 1.
    To ensure that the Autovent is not overloaded and that head room or growing space is not reduced. It is most important that the gap between the straight link and the glass in the vent is the same at both ends when the vent is closed. See Fig. 2.
When the Autovent has been fitted, take the knurled adjuster screw from the fixings pack and slip it over the piston rod. If necessary, open the window with one hand and screw the knurled adjuster into the swiveling block until the Autovent unit holds the window open 1/8” when you lower it slowly and take your hand away. Setting is best carried out when there is no wind blowing through the window and when the temperature measured by a thermometer placed or hung by the Autovent unit indicates the temperature at which you wish the vent to start opening.
If you wish the Autovent to start opening the window at a higher temperature, screw the adjuster out of the swiveling block and vice versa, but make sure that at least four threads on the adjuster screw are engaged.

Other Information:
The Hydraulicheck is designed in such a way that it will not open in cold or windy weather. It is fitted with a strong stainless steel spring to hold it steady, but in high winds other windows and doors should be kept closed.
At full stretch on a hot still day the Hydraulicheck will give a maximum opening of approximately 12”. It should not be harmed by low temperatures and can be left on the window throughout the year.
If there is an existing vent stay, this should be removed or fastened in such a way that it cannot stop the Hydraulicheck from working.

Common Recommendations:
To determine the weight of your vents, you will need a pole and a scale. While holding the pole step on the scale and note your weight. Next, place the scale under where the vent is located, stand on the scale and push the vent open fully with the pole. Note the weight as you are lifting the vent. The difference between the first weight and the second weight will determine how much the vent weighs.
If the weight of the vent exceeds the weight load capacity for the vent opener, two vent openers may be recommended.
If two vent openers are used for one vent, it is very important that the vent openers are operating at the exact same temperature. If not, the vent frame may end up getting slightly bent.

Replacement Parts:
Replacement Cylinder Item # 3510.

For further information, please contact Charley's Customer Service at 1-800-322-4707.

This item is backed by Charley's 100% guarantee. If you are not completely satisfied, return your purchase in the condition you receive it, within 30 days, for a refund, exchange or credit - whichever you prefer. If any product is found to be defective within the first year, it may be returned or exchanged for full credit.