How to perform a hot water meter accuracy test

Summary

We provide hot water for many apartment buildings from one shared system, called centralised hot water. Every apartment has its own meter, so you only pay for the hot water you use.

If something looks off on your bill, you can do a simple accuracy test to check. While this test won’t prove a fault, it’ll help you decide if you need to contact us for more help.

Could your hot water meter be faulty?

Hot water meters are simple devices, built to last, so major faults are rare. Most faults cause the meter to slow down over time, which means they record less hot water than you actually use.

To keep things accurate, we replace or repair meters if we find faults. If your bill went up after we installed a new meter, it usually means your old meter was running slow.

Where to find your hot water meter

Before you start the test, you need to find your meter. In most apartment buildings, meters are in a common area such as:

a hallway cupboard
the garage or basement
behind a wall or ceiling access panel
in the corridor on each floor.

Sometimes the meter is inside your apartment. Check under your bathroom vanity, the kitchen sink, or behind a hidden panel in the wall.

Tip: Gas or cold water meters can look similar to hot water meters. Match the meter number on the unit to the one on your hot water bill. If you can’t find it, contact us and we can give you the exact location and access details.

Stay safe while you test

Only try this test if you can stand flat on the ground next to your hot water meter. Have a quick look for spiders or other insects first.

Don't open any box, panel or door marked with a danger, no access or high voltage warning on it. Those signs are there to keep you safe. If you can’t get to your meter safely, immediately stop and contact us to check for a fault.

Step by step: The simple hot water meter accuracy test

You’ll need a 10 L bucket. Follow these steps to check if your meter is reading correctly:

Turn off every tap inside your apartment.
Go to your meter and take a clear photo of the meter number and the current reading.
Place the bucket under your kitchen or laundry tap.
Turn on the hot tap. If you have a mixer tap, push the handle all the way to ‘Hot’. Start filling straight away. You don’t need to wait for the water to run hot.
Stop the tap when you’ve filled exactly 10 L. You can let the water cool and use it to water plants.
Go back to the meter and take a second photo of the reading.

What your results mean

Now compare your two photos.

The meter numbers went backwards

If your meter numbers are going backwards, it could mean your tempering valve has a problem. The tempering valve controls how hot your water gets – and when it's faulty, water can flow the wrong way through the meter. This is called backflow, and it makes the meter count down instead of up.

Because backflow affects how accurately your meter reads, it's worth identifying and fixing the cause before we check whether your meter is reading correctly.

Just so you know, Origin looks after the meter itself. The pipes and plumbing on your side of the meter are your responsibility to maintain – but we're here to help you work out the next steps.

Here’s what to do next:

Get the backflow checked: You’ll need a plumber or gas fitter to inspect your plumbing. If you’re renting, let your landlord or property manager know so they can arrange it.
Keep us in the loop: Email your meter test photos to hello@origin.com.au or contact us and let us know your meter has moved backwards and you’re getting the potential issue looked into. The more detail you can share, the better.
Tell us once it’s fixed: Get back in touch when the issue is repaired. We’ll review your usage and work through any bill concerns with you.

The meter recorded no usage

If the meter didn’t move at all, it’s likely faulty and we’ll need to investigate. Email your test photos to hello@origin.com.au or contact us and let us know your meter recorded no usage from a meter accuracy test.

The meter recorded 10 L or less

Good news, your meter is likely working correctly. It isn’t over-recording your usage.

A reading under 10 L is also normal. Many apartments have a tempering valve, the part that controls how hot the water gets, which mixes in some cold water before it reaches your tap. So even when you fill a 10 L bucket from the hot tap, the meter only counts the hot water that came through, not the full 10 L.

If you still need help, visit our Help & Support page, email hello@origin.com.au or contact us.

The meter recorded more than 10 L

If the meter recorded more than 10 L, it might be faulty and we’ll need to investigate. Email your test photos to hello@origin.com.au or contact us and let us know your meter recorded more than 10 L of usage from a meter accuracy test.