*PLUMBERSSTOCK EXPERT* responded:
Hello there! Thank you for posting a question under the Sloan - WEUS-1000.1403 Urinal. There are a lot of reasons why this is happening. One would be because the diaphragm, which is located inside the flush head, needs replacing. Here at PlumbersStock, we have a wide range of Replacement Sloan Royal Diaphragms to choose from. You could check this Parts Sheet for reference. If you have a different urinal, please give us the made and the product number so we can further assist you. Thank you for choosing PlumbersStock.com. Have a great day!