1 Fill valve
The cistern won’t fill or won’t stop filling
This valve lets water in after a flush. If it sticks shut, the cistern may refill slowly or stay empty. If it won’t shut, water can run into the overflow.
AquaFix plumbing services
Toilet cistern, fill valve and flush repairs
If water keeps trickling into the bowl after the flush, the cistern may be filling too high or letting water past its flush seal. A slow refill, a silent cistern and a button that does nothing each point us towards different checks.
Inside a typical cistern
Three parts, three different jobs
Match what you notice to the parts we would check. Toilet designs vary.
2 Flush valve
Water keeps running into the bowl
The valve releases the stored water when you flush. If the seal at the bottom won’t close, water can keep trickling into the bowl.
3 Flush button
The button is loose, stuck or does nothing
The button operates the flush through a cable, rods or another link, depending on the cistern. We check the control and the connection.
What you might notice
- Water keeps trickling into the toilet bowl
- If the inlet valve keeps letting water in, the level can reach the overflow and drain into the bowl on many modern toilets. If the level drops when the inlet shuts, water may be passing the flush-valve seal.
- The cistern does not fill, or fills very slowly
- We check the water supply to the cistern and the fill valve. The valve may be restricted or failing to open. A toilet can flush once from stored water and then fail to refill.
- The cistern refills by itself every few minutes
- Water may be leaking slowly from the cistern into the bowl. When the level drops far enough, the fill valve opens again. We look for where water is escaping before replacing a part.
- The push button or handle does not flush
- The control can become loose, stick or stop moving the mechanism. Depending on the cistern, it may use rods, a cable, an air tube or a lever.
- The flush is weak or only one button works
- We check the cistern water level, how the two buttons operate and whether the flush mechanism lifts as intended. If the bowl itself drains slowly or rises, we also consider a waste blockage.
What the parts do
- Fill valve or inlet valve
- This lets water into the cistern after a flush and shuts off at the correct level. A faulty valve can cause slow filling, no refill or water running into the overflow.
- Flush valve or siphon
- This releases water from the cistern when you flush. Some toilets use a siphon. With a flush valve, a seal that does not close properly can let water creep into the bowl.
- Button, handle and linkage
- These tell the flush mechanism to open. We check how the button or handle connects to the mechanism before deciding which part needs work.
- Concealed cistern
- A cistern behind a wall or furniture may be reached through a flush plate or access panel. A photo of the front helps us discuss the type and available access.
What we can do
We assess how the cistern fills, holds water and flushes. Where accessible and appropriate, we can replace compatible inlet valves, flush valves, seals or controls and check the refill and flush after repair.
Before you get in touch
Tell us whether water is running into the bowl or onto the floor, whether the cistern refills, and whether this is your only toilet. A photo of the toilet and flush button helps. Leave a fixed panel in place.
Planning your visit
What happens next
Describe the job
Send your postcode, what is happening and a photo if it helps. Tell us if water is still escaping.
Agree the visit
We confirm availability and explain the basis of any attendance or investigation charge before booking.
Agree and check the work
We explain what we find, agree any further work and check the affected plumbing afterwards.
Common questions
How can I tell a fill valve fault from a flush valve fault?
A fill valve that will not shut can send water down the overflow. A leaking flush seal can let the stored water level fall and cause repeated top-ups. We check the water level and how the fittings behave to tell them apart.
Is a puddle around the pan the same as a running cistern?
A trickle inside the bowl points us towards the cistern. Water on the floor can come from the cistern, supply or waste connection. If there is a leak outside the toilet, tell us when it appears.
Can you give me an estimate?
We discuss the work and the basis of any attendance or investigation charge before booking. Where the fault or access is uncertain, we may need to assess it first. We discuss any change to the agreed scope before additional work.
Tell us what needs attention
Have your postcode and a short description ready. If water is still escaping, call us.