Before purchasing a replacement piston firstly check that piston rod is located in the hole in the top block.
The rod is designed to disengage in windy conditions and may need to be reset manually. If the piston has stopped working you may be able the slide the piston assembly out from the bottom block by loosening the m6 bolt in the block.
Earlier models prior to 2007 have a smaller diameter hole in the bottom block that will not allow the piston assembly to be withdrawn. In this case a new complete ridge autovent will need to be purchased.
If the placement of your piston is correct and is still not working the piston will need to be replaced. These are available to purchase for £20 each. As the pistons are filled with an organic wax compound there is no specific expiry date however we do offer a 2 year warranty.
If you are unsure as to whether or not you need a replacement piston please feel free to call us on 01829 271888. One of our team will be happy yo assist you.