Baxi Isolation Valve Top 7740204

The Baxi 7740204 is a top isolation valve manufactured by Baxi for use in its 800 series system appliances. It sits on the upper connection point of the appliance and allows the water circuit to be shut off locally, so the boiler can be drained, serviced or have components replaced without draining the wider heating system. The valve is operated by a screwdriver slot on the spindle and is a serviceable item that can weep or seize over time.

• Water weeping from the valve body, spindle or compression joint
• Damp staining or corrosion on the pipework directly below the valve
• The isolation screw is stiff, rounded or will not turn when the appliance needs isolating
• Scale or mineral build-up around the valve, restricting operation
• The appliance cannot be isolated cleanly before a service or repair

• Check the appliance GC number or serial number against the compatibility list to confirm this valve suits your model.
• Cross-reference the alternative part number 1795798 against any documentation supplied with the appliance.
• Have a suitable sealing washer or gasket to hand, as the existing seal may need replacing once the valve is disturbed.
• This part is fitted to a gas appliance; installation must be carried out by a Gas Safe registered engineer.