Flow Through Kit - New Range

Unvented Accessory

Speedflow, Powerflow, Superflow


Flow through expansion vessels help to prevent any build-up of harmful bacteria by ensuring that water keeps flowing through the system. They are increasingly being specified and required by local water companies in healthcare, public and hygiene sensitive settings including schools, hospital, offices and council buildings.

Flow through expansion vessels can be used with all unvented water heaters including Speedflow, Powerflow and Superflow.



• Designed to allow flushing through the vessel by taking water flowing through the system and pushing it inside the vessel
• Helps to prevent contamination or stagnation
• Reduces the opportunity for bacteria to develop
• Includes flow through anti-legionella valve and T- piece
• Valve connects to the expansion vessel
• Incorporates isolation shut-off valve to allow maintenance of the expansion vessel
• Plug allows the system to be drained
• Vertical orientation
• Easy to fit
• WRAS approved

For Speedflow flow through expansion vessel kits add suffix FT to the kit code e.g. SF3FT

For Powerflow & Superflow (kit included with the unit) add suffix FT to the product code e.g. PF30SFT

Technical Specification

Water System

For use in potable water systems


Valve: Brass body incorporating spherical valve

T- piece: Brass


Maximum working pressure 10 bar

Maximum operating temperature 65°C

Plumbing Connections

Connects to 15mm copper pipework


The expansion vessel must be installed vertically with connections at the base. The water divertor paddle in the valve must be aligned as per the product instructions


For expansion vessel dimensions see either Speedflow accessories page or Powerflow or Superflow product page.



Standard Warranty

5 years parts or replacement

Data Tables

Product CodeDescription
SF3FT2L expansion vessel, check valve, flow through valve and T - piece
SF4FTAs SF3FT plus pressure reducing valve
DescriptionHeight (mm)Width (mm)Depth (mm)
Flow through valve and T - piece (combined)1156550