Bayliss XL Autovent - Automatic Greenhouse Window Opener - Temperature Sensitive Solar Vent Opener

Bought to replace a broken window system in an old metal greenhouse. It's been commented as 'easy to install' whilst this is true, it is not difficult, it IS fiddly. The instructions are very clear and very good, it can be fitted on a lip present in metal framed greenhouses or screwed into a wooden greenhouse frame. We have metal so I can only really comment on this. So, it uses a metal lip on the hinged window and a metal lip on the frame below this window. It basically makes a 'vice' between the metal lip and a metal plate you 'screw' onto the contraption. You are tasked with creating this vice on one side of the item and tightening it into place and then flexing it to get the vice on the other side. It basically needs you to put pressure on the spring and to hold and tighten the vice at the same time. It would absolutely be easier with four hands, so if you think you might struggle, borrow a friend for a few minutes. But the time needed to fit it, is very much so, about 4 to 5 minutes (not including half an hour in the fridge so get the gas chamber easy to fit- you don't want it expanding in the heat as you work on it - covered in the instructions). Easy to install, but a bit fiddly if you're by yourself. It arrived quickly, installed quickly and we noted the next day in the variable warmth of early May, it was working, both to open and close carefully. Very happy with the product, opens a lot wider than the one we had before (it was about 10 years old) and the tomatoes seem to like it. Be careful when you tighten the hinge to close it using the end screwing system at the final stage of the process, the metal was a bit sharp and again, quite fiddly to get fingers in, use a tool or wear gloves or it may scratch your knuckles/fingers as you turn it.

Looked at a few options before settling on this one. Wanted an opener for my small palram lean to green house, the important attribute was the piton being incorporated into the scissor sections and not protruding as with other brands as this would foul on the limited room and clearance. I had it fitted with the easy clamping system in 10 minutes, it is pretty easy but also a bit fiddly. If you’re a handy diyer or played with mecano as a kid you’ll find it simple enough. I Chilled the piston as per instructions, fitted it and adjusted things and then watched in amazement as it slowly opened the window as and when the sun warmed things up a bit. I checked at end of day and it’s closed down again. Time will tell but so far pleased with it, might add some pictures in time. Hoping the plants will get optimal warming but not get cooked compared to me manually guessing a good setting for the window and door as I remember to do it. Chose this one for the neat and clever design, it’s a known make so should be good for spares in the future, plus it’s made in Britain, also a #1 best seller.

Have used these exact same openers in the past with older greenhouses and had absolutely no problems fitting them. With my new greenhouse however came close to cracking the glass as bolts protrude slightly too far, luckily realised in time before any damage done. As greenhouse has the appropriate holes for fixing an opener decided to fit it properly using bolts rather than the supplied clamp plates. Opener itself operates perfectly. In summary I'd recommend these so long as you're careful when fitting.

I have had these fitted on my greenhouse windows since 2023, and they have never failed to open, no problems,

Watching the vent open and close on the greenhouse is like magic. It's such a simple idea, but it works brilliantly. I like that the piston on this one doesn't hang down as most of the others do. It's inline with the bracket, so you aren't going to hit your head on it and break it or hurt yourself. The device feels robust. I don't know what the life of a cylinder is, but replacements are relatively inexpensive and could be fitted without detaching the device. Installation was a doddle. I did it on our aluminium greenhouse while the children were getting dressed for school (having put the piston in the fridge overnight). If you're installing it into an aluminium greenhouse, put the instructions down and watch the video on the listing or search on YouTube. There's a short video that is really very clear. For a wooden greenhouse, it's the same but you screw it into place. I'm so impressed that I bought another for the other vent. :-)

Whoever it was who stared long enough at their greenhouse window and said i know i will fill a piston with wax and when it melts and sets it will open and close the window deserves a special acknowledgement in practical science. Such a simple device yet so cleverly thought out as to not require electricity. Just fitted the Bayliss XL to one of my greenhouses as I can't monitor it everyday or manually open and close the window which will stress the health of my tomatoes, cucumbers, chilliles, squashes etc. After unpacking it I immediately sliced a good cut to my finger from the super sharp edges of the lower bracket arm (the upper bracket arm is not sharp) so be extra careful or wear gloves or use a burr tool to remove the sharp edge of the metal. Installation was just a little bit of organised thought, orientation, checking fit etc. the clamps fitted nicely to the aluminum flap on the window. For the top bracket connecting to the window itself the 2 bolts were a bit long and pressed too close to the glass pane once tightened, so I had to improvise about 3-4mm of stacked washers to keep the small pressure point of the end of the bolts away from the glass which could get cracked or smash the window pane (maybe auto-vent companies could supply a few washers to go with the bolts to help). I didn't have to put the wax piston in the fridge prior to installing as luck would have it it was hail and snow cold today, but tomorrow it is to be 15 degrees outside and probably 40 degrees in my greenhouse, welcome to the new norm of UK weather 2024! Time will tell how well it functions and how durable it is but overall I am happy about having an auto-vent system, a clever solution to a big greenhouse problem, for a good price and fast delivery. If it Works well I will be buying more as I have 5 large aluminium greenhouses that need them, possibly a louvre auto-vent too.

5 STAR PRODUCT BUT 3 STAR INSTRUCTIONS. I HAD TO USE FIXING RAIL SYSTEM ON MY NEW ALUMINIUM/POLYCARBONATE GREENHOUSE TO GET IT FITTED USING NUTS I HAD THAT FITTED THE SUPPLIED BOLTS. THE ROD THAT SCREWS INTO THE PISTON WAS FIDDLY TO GET IN AND YOU NEED TO SCREW IT IN QUITE A WAY CLOCKWISE BEFORE YOU CAN THEN RE-ADJUST IF NEED BE. ONCE FITTED THOUGH IT IS A GENIUS PRODUCT; SIT BACK AND WATCH IT OPEN AND CLOSE ON ITS OWN. I CALL IT THE WEATHER WINDOW - YOU DONT NEED TO CHECK THE FORECAST NOW, JUST LOOK OUT AT THE WINDOW !

These are not the first ones I have bought. They operate very well and the ones well already have are still working fine after many years. For me the only problem is that they won't close when it rains on a very hot day as they are temperature controlled not humidity controlled