Weighted Anti-Vacuum Valve, 3/8″ BSP

This is the weighted version of the Rancilio-style anti-vacuum valve. A brass hex cap sits over the stem and adds weight so the valve seats firmly as the boiler heats. It screws into a 3/8″ BSP port and stops the boiler pulling a vacuum as it cools down.

Why the weight matters

The cap helps the piston drop shut quickly and stay closed at low pressure, which cuts down on the hiss and water spitting some machines show while warming up. The body, cap and piston are brass, with an O-ring seal on the boiler side.

Specifications

Anti-Vacuum Valve 3/8″ with Weight Thread: 3/8″ BSP male
Anti-Vacuum Valve 3/8″ with Weight Material: Brass
Anti-Vacuum Valve 3/8″ with Weight Top: Hex weight cap
Anti-Vacuum Valve 3/8″ with Weight Seal: O-ring piston
Anti-Vacuum Valve 3/8″ with Weight Ref. number: 1523651 (supplier)
Anti-Vacuum Valve 3/8″ with Weight Pack: 1 valve

Machines it suits

According to the old listing it fits Rancilio Classe 7 E/S, Classe 9 S and USB, Xcelsius and Epoca E/S machines. Compare it with your old valve: if there is no cap, pick the plain anti-vacuum valve. A worn 3/8″ boiler safety valve is another common fault on older machines.

Boiler parts are best fitted with the machine cold and drained; our Melbourne repair service can fit it for you. Browse more spare parts.