DVD Check Valve Suitable for HVAC Applications

DVD Valves has launched the DVD swing check valve with dashpot, for use in applications or projects that have a risk of surge, such as heating, ventilation and air-conditioning (HVAC) systems. The company claimed that if an application has a risk of surge, it is not wise to use standard swing check valves. This is because in case of a surge, water columns that are flowing back can hit the check valve fast, which can burst down the entire system.

In the DVD check valve, the dashpot makes the door of the valve close very quickly until some critical point, leaving a small gap for some water to pass through the valve, and then slowly seals the door tight. The dashpot acts like a cushion in case the door shuts down suddenly.

Using this solution, a small amount of water, which does no harm to the system, is let through the valve, dropping the surge. The check valve seals tight when surge conditions disappear. A key application for the product is HVAC systems. In addition to surge and water hammer prevention, the check valve also decreases the amount of noise generated by the system. DVD is producing check valves with dashpot at a range of O300-1,000mm.

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