Proqual Toilet Flapper (PQ-309): Stop a Running Toilet
By Maintenance Depot Plumbing Team · Last reviewed
Quick answer
The Proqual PQ-309 toilet flapper seals the flush valve at the bottom of the tank. Replacing a worn flapper is the most common fix for a toilet that keeps running.
A toilet that keeps running, or refills by itself every few minutes, is usually leaking past the flapper. The Proqual toilet flapper (PQ-309) is a simple replacement that can stop the waste.
Specs at a glance
| Spec | Detail |
|---|---|
| Product | Toilet flapper |
| Brand / model | Proqual PQ-309 |
| Function | Seals the flush valve between flushes |
Signs your flapper is worn
- The tank refills on its own ("phantom flushes")
- You hear water trickling into the bowl
- You have to jiggle the handle to stop the water
Quick dye test
Put a few drops of food colouring in the tank and wait 15 minutes without flushing. If colour appears in the bowl, the flapper is leaking.
How to replace a flapper
- Turn off the water at the stop valve and flush to empty the tank.
- Unhook the chain from the flush handle arm.
- Slide the old flapper's ears off the pegs on the overflow tube, or remove its ring.
- Clean the flush valve seat with a cloth or fine scrub pad to remove scale.
- Fit the new flapper and reconnect the chain with about 1/2" of slack.
- Turn the water on and test several flushes.
Still leaking?
- Check the chain length.
- Inspect the flush valve seat for cracks.
- Check the fill valve: water running into the overflow tube points to a fill valve problem.
Maintenance Depot stocks fill valves, flush handles and toilet outlet valves too.
Frequently asked questions
How do I test for a leaking flapper?
Add food colouring to the tank and wait 15 minutes. Colour in the bowl means the flapper leaks.
How long does a flapper last?
It varies with water quality, but worn, warped or hard flappers should be replaced.
Why does it still leak after a new flapper?
Check the chain length and the flush valve seat for scale or cracks.