Heavy-Duty Greenhouse Window Vent Opener - Automatic Solar Heat Sensitive Kit, Supports Up to 15kg Load with Twin Double Springs

Very good quality product. No I don’t have a stress when I go to work or on holidays who will open and close my greenhouse. Works like it should. Opening when +17 or get direct sun, and close back when temperature drops down. Highly recommend for everyone who has a greenhouse.

Instructions were bobbins. I recently installed a genuine Vitavia vent. The instructions were bobbins for that too. This vent is better than the genuine Vitavia item, easier to install and half the price.

No sign of leakage from the cylinder. So supposing that you get the same product as I did two years on, it's pretty good.My main criticism is that the product delivered is not as shown in the entry, where the cylinder sits out of the way roughly parallel to the glass. Instead, the cylinder sticks down quite a way so I will have to be careful not to catch it with my head.On the positive side, the different product comes with different instructions complete with a diagram that shows the cylinder sticking downwards. Criticism of the instructions in earlier reviews therefore no longer applies - I found them clear, with plenty of diagrams and descriptive text. It took me a bit less than an hour from opening the box to having the product fitted. In retrospect, it would have been quicker to remove the pane of glass below the hinged bit to give access to fit the lower part of the assembly and enable me to drill holes without great care.One reviewer suggested putting the cylinder in the fridge before fitting it. Another option is to stand on a small step ladder and open the window until the holes line up. The potential snag with this approach is that if you slip, the end of the cylinder could go through the glass. Again in retrospect, I could have avoided that risk by putting a paper clip temporarily through the upper hole in the collar before fitting the split pin in the lower hole.It was thoughtful of the supplier to provide a spare screw of each type and a spare split pin. They are, indeed, easy to drop and lose - particularly the split pin. To be on the safe side, I slipped a colourful bag tie through the hole at the end of the split pin to make it easier to spot it on the ground.

I found the instructions useful plus watching the Video helped too. Mine didn't work on 1st attempt. I contacted the manufacturers and the were swift to respond. Advising to put it in the fridge. Which I had already done. So I popped it into the freezer for 20 Mins and push the ram gently and it went back into the cylinder. So my advise would be try the fridge route 1st. If that doesn't work. Try a short time in the freezer. By the time I had refitted it. It was too cool outside for it to want to open. So with fingers crossed I waited for next morning. Hey presto it works.

As with most any window opener the temperature at which it opens is fixed, and how much the window opens is none linear.It is really too early to review this item properly given that many of these window openers fail after a period of time, however to date, this one has proved to be reliable and does the job.I find that having the expander tube inside the greenhouse works well, detecting the heat of the sun through the greenhouse glass thus giving a better opening adjustment to the heat inside the greenhouse. Other tubes have the expansion tube in the opening, thus if you get a breeze that is cold, the window does not open properly and the greenhouse overheats.3 star only because a long enough period has not passed to assess this properly, but going by present data, I would make it 5 star.Ideally I will need to have a bottom vent installed, to allow circulation of air, cooler air in, with the window opener on top and some way of opening the vent in synchronisation with it. Given that the arm tilts when the window opens, I will probably use a pulley system so that this opens the bottom vents at the same time as the window. :)

very good

Bought two of these to replace similar units on a 20 year old greenhouse which had stopped opening. One of the two had to be replaced immediately because of a manufacturing defect (to be honest can't remember exactly what now). Apart from that was initially happy - the openers were easy to fit and opened well when the greenhouse became hot.Now after just over two and a half years one of the units has failed - looks as though one of the spindles on the pivot close the cylinder has broken. Presumably poor manufacturing or materials used is to blame. Contacted the seller but they refused to replace because the guarantee is only 12 months. Strange how the original units lasted almost 20 years! My advice is to avoid these.

Wish I had read these reviews before I attempted to fit this item. I too spent over an hour trying to fit this thing. The problem was that I followed the written instructions - DO NOT DO THAT! Follow the figures only so that you completely assemble the item and then it will be easy to fit. DO NOT mount the window operator before you have completed the steps illustrated in figures 4 and 5. I tried to do these steps after the operator was mounted and found it really difficult because you have to reach upwards with the operator close to the glass, so not much room and not enough room to use tools except a screwdriver. This should have been, and would have been, a five minute job if I had followed the figures instead of the written instructions. I mean this is the third autovent I have installed so it's not as if I lack experience but I thought that I should follow the written instructions anyway, big mistake, should have just done it my way. During my messing around trying to put the cylinder in the contraption one of the nuts holding the cylinder collar, item 3, came loose and fell off three times. After the third time I couldn't find it so have to hope it will still work with one nut. Please read and learn - assemble the whole thing COMPLETELY before you attach it to the vent. No idea if this thing works, don't care anymore, don't know who wrote the instructions but they have obviously never fitted this item.