My toilet's flushing system is hissing...

Bills do like to come around end of the month, don't they?  I got a shock the other day when my water bill arrived, it's $100 more than the average.  I checked the bill details and found out the sewage charge is way more than usage.

Let me guess, this could be due to

• People in the house is peeing and shitting more often
• The sewage meter is malfunctioned
• Somewhere is leaking!!

I called a local plumber (which I found his contact from TrueLocal) and got the second shock.  They're going to charge $60 on arrival to the property (even though they're based in a neighbouring suburb), $20 for every 20 minutes.  It would take them at least 1 - 2 hours to carry out leak investigation and fixing.

Looking at my dry wallet, I decided to fix it on my own, the most suspicious thing would be the hissing sound coming out from the toilet's flushing system.  The hissing noise will stop if I twist the screw a bit tighter.  But when water refills the tank, the noise starts again.  Googling the issue leads me to exchange of a flapper in the outlet valve of the flushing system.

Steps to do to confirm a leak:

1. When the water tank is filled, turn off the water supply where the minitap is normally situated below the flushing system.
2. Come back after 15 - 30 minutes, check if the water level has dropped.

In my case, the water tank has gone empty.  Right, leaking issue half solved!  In order to let the professionals to identify the exact problem, I disassembled the outlet valve and brought it to Bunnings.  Have the wrong size of flapper substituted (it's still leaking!), I then drove to Caroma service centre and bought another flapper (price is < $2.00).  Once it's fitted into the outlet valve properly, all fixed!

TIL

• water company charges any amount of water coming in and going out of the property 
• not all flappers can fix a leaking valve, even though they look very similar.

Step-by-Step Guide

Turn off the water supply

Take out the middle (yellowish) outlet valve, the right  cylinder is the inlet valve

The outlet valve structure, flapper is shown as the black rubber plate at the end to prevent water from flowing into the toilet bowl

Replace it, the old one may look bigger as it has inflated along the years.  The new flapper as seen in the packaging is the wrong one that I've bought from Bunnings

Remember to slightly turn the platform that holds the flapper clockwise until they're firnly attached.  Install it back, mission accomplished!!