708 Generic 550kPa Pressure Limiting Valve, Plastic, 1/4 Inch Quick Connect, Universal Water Filter and Fridge Water Line Part

Item 708 is a compact 550kPa pressure limiting valve with a plastic body and 1/4 inch quick connect fittings. It suits water filter systems, ice and water fridge lines and other small bore water connections where mains pressure can run higher than the equipment is designed for. This is a generic universal part, so it is not tied to any one brand of filter or fridge.

Why fit a pressure limiting valve to a water filter

Mains water pressure varies through the day and can spike well above normal, especially overnight or when nearby taps shut off quickly. Filter housings, push-fit fittings and fridge inlet valves are built for a certain working pressure, and repeated spikes can lead to cracked housings, weeping joints or a burst line under the sink. A pressure limiting valve sits in the supply line and holds the downstream pressure to no more than 550kPa. If you have had unexplained leaks at your filter or fridge connection, high pressure is worth ruling out.

Part details

• Limits downstream pressure to 550kPa
• Plastic valve body
• 1/4 inch quick connect fittings
• Universal fit for 1/4 inch tube on filter and fridge lines
• Generic aftermarket part

Installing the valve

Turn off the water supply and open a tap downstream to release pressure. Fit the valve on the inlet side, ahead of the filter or fridge you want to protect, with the flow arrow pointing towards the equipment if the body is marked. Cut the tube square, push it firmly into each fitting until it stops, then restore the water slowly and check for leaks. Connections to the mains supply may need a licensed plumber.

Questions about this part

Will this fit my 6mm tube?

The fittings are 1/4 inch quick connect, which is about 6.35mm. Metric 6mm tube is slightly smaller and may not seal reliably in a 1/4 inch fitting, so use 1/4 inch tube or a suitable adaptor for a leak free joint.