How do I fix a cistern that is noisy when filling?
Try turning the water tap connecting water to your toilet – reducing or increasing the flow of water may quieten the noise. If the water flow is too high, you may be experiencing noise from water hammer, as the pipes jolt from the sudden influx of water. If the water flow is too low, you may experience a whistling noise as the water tries to pass through a small gap. Another issue could be dirt or grit getting stuck in the inlet valve, which can cause a noise as the valve opens and closes. Try turning off your water supply to the toilet, remove the inlet valve, and clean the headseal washer. If the noise continues (and you have an older inlet valve), it may be that the rubber washer has deteriorated. In this case, you may need to replace your headseal washer, or the inlet valve.
