All non return valve will allow a stream of water from the pool to flow in one direction but will prevent any flow back from exiting the pipe. Due to an NRV, a person cannot return to the pool after swimming or diving all the way from the opposite end.
Connect the flow of the return hose to the NRV at the overflow, the return hose then goes inside the pool with the power of the pump. The NRV will stop any water from going back the way it came.
NRV 50mm for pool heating allows water only one way, so your heater is maximized efficiency. Designed to maximize efficiency, these effective non-return valves have a one-way valve that lets water run through the center of the three-dimensional NRV which lets the water out but no one in.
This saves you money in your heater’s running costs as you are no longer using and wasting Heat.
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