Burp Valve screws into 1 1/2" and 2" Bulkhead Fitting (sold separately) Relieves the air and water that can build up under pond liners. This is a spring loaded device that opens at around 90 PSI. Then when the pressure is relieved the valve will close back again. A minimum pond depth of 5ft is recommended to get enough pressure for this item to work. The hydrostatic relief valve threads into a 1-1/2" bulkhead fitting. A hydrostatic relief valve (commonly referred to as a burp valve) is placed at the bottom of an in-ground pond or swimming pool. Its purpose is to open when excessive ground water pressure builds up allowing the ground water into the pool. These valves are most important during construction or when the pool needs to be drained. While the pool is empty, there is nothing weighing the pool down. It is at this time the pool vessel is most vulnerable. Without a hydrostatic relief valve, high ground water pressure could lift the pool out of the ground. The hydrostatic relief valve is installed upon installation of the pool, or when renovation work is being done. It is secured into one of the main drain ports.
