How to Replace a Toilet Inlet Valve Diaphragm (UK)
Fit a new diaphragm on Torbeck, Fluidmaster and Ideal Standard fill valves without replacing the whole valve.
TorbeckFluidmasterIdeal Standard
When a diaphragm fixes it
Weeping fill valve that runs slowly — diaphragm has hardened. Full flow issues — usually not the diaphragm; replace the whole valve.
Fit
Isolate. Twist off top cap of valve. Lift out diaphragm. Fit new one. Reassemble and test.
Frequently asked questions
- Is it worth replacing the diaphragm or the whole valve?
- <3 years old — replace diaphragm (£2). >3 years — replace whole valve for reliability.
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