Can I buy a non-return valve for my sprayer? 02 September 2020 13:27 Updated Yes, these can be purchased in garden centres or from our Consumer Service department by emailing email@example.com. Related articles Why is my sprayer losing pressure? Where can I buy spare parts? Why is my Knapsack Sprayer not pressurising? How can I locate a leak in my sprayer? Are your plastic lances as resistant as the aluminium ones?