There is no complication to testing your hot water at home in Australia. With a digital or probe thermometer one has all that is required: run the hot water for 30-60 seconds and put the instrument to the flow. In the majority of Australian households you will find the water coming from household and bathroom outlets is in the region of 50°C; storage systems are often set to 60°C as a means of keeping Legionella bacteria in check.
Damian Rockwell here. I have found that hot water issues do not tend to make much of an introduction. One day the tempering valve may be the most untrustworthy member of the household, the next the kitchen sink is lukewarm and the bathroom tap scalds. Put in the time for a proper test and it will tell you if you are dealing with normal variation, a matter of settings or something that calls in a licensed plumber.
Test Tap Temperature Safely
It is good practice to measure the hot water for the sake of comfort, to stave off burns and do some elementary troubleshooting. It provides information of value before you ring a plumber and there is no need to get to work on the hot water system or put your hands near any electricals. See the 2026 hot water temperature regulations for more information.
The way to do it is to test the water right at the hot water tap. Putting your hand in the stream is not advisable. Skin is not a very good thermometer and for those with less sensitivity, the elderly and children, a burn can occur before the heat registers.
A few simple steps
- Get a container that is clean and can stand the heat.
- With the tap turned fully on, put the thermometer probe in the middle of the stream, making sure it does not come in contact with the container.
- Let the water run for half a minute or so.
- Once the figure has stabilised, note it down.
- Then go to another outlet like the laundry or bathroom and do the same.
The point of running the tap is that water left in the pipe can be of a different temperature to what is coming from the system, which is more of an issue in a long house or where the hot water system is some distance from the bathroom.
Be steady with the container and do not let it splash. Above 50°C hot water will do damage to skin in short order. And if you see particles or the water has an odd smell or cloudiness, put a stop to it and seek professional opinion.
The Right Thermometer
You are better off with a dependable digital model. There is no call for anything from the laboratory but the device should be able to give you an accurate liquid reading from 0 to 100°C.
A food thermometer with a clean probe will do, as will a purpose made probe unit. An infrared on its own is not to be trusted with moving, shiny water.
Before you start
Have a look at the thermometer. The probe must be undamaged and in good order. If the maker puts forward a calibration or ice-water check, do not dispense with it.
When you are at the tap, hold the thermometer firm and keep your fingers clear of the hot water; take it out if the numbers go up for no reason. It is an aid, not a warrant for having a tussle with a boiling tap.
Make a note of the outlet and the temperature and when the tap was last used for your records. It may show a pattern with the bathroom running hot and the rest of the house normal.
Australian Temperature Limits
Requirements for hot water tap temperature in Australia are dictated by the plumbing regulations in force, the outlet and the nature of the premises, so one size does not fit all. For a typical domestic setup 50°C is the safety mark at sanitary outlets. In healthcare you might see 45°C given the propensity of patients to be scalded. Your licensed plumber or the authority can advise on what is called for.
| Part Of The System | Common Temperature | Why It Matters |
|---|---|---|
| Storage hot water system | 60°C or so | To deal with Legionella in the stored water. |
| Household hot water outlet | About 50°C | A good compromise between what is practical and the need to prevent burns in most domestic installations. |
| Healthcare outlet | About 45°C | Affords those at risk of burns extra protection. |
Such numbers are for reference only; they do not give licence to tinker with a system on one’s own. One has to take into account the plumbing work and the property itself when it comes to compliance. For an authoritative view of what the national building and plumbing requirements are, the guidance from the Australian Building Codes Board is a sound place to begin.
Then there is the matter of the pipework: as the water makes its way through it the temperature can vary a little. So a 48°C reading at one point and 50°C at another is not in and of itself a sign of trouble. But where there is a marked discrepancy or a sudden change, or the water is plainly scalding, then it warrants a look at.
Why 60°C in storage?
You will find many hot water systems store at 60°C yet put out something cooler. It is to guard against Legionella bacteria which can thrive in stagnant warm water and lead to serious illness should droplets be inhaled.
The tank must be at a temperature conducive to safe water management but the outlet requires control to forestall scalding. A tempering valve or thermostatic mixing valve is called for here.
How Mixing Valves Work
The tempering valve takes cold water and blends it with the hot from the storage before it gets to the tap, thus bringing the temperature down to a safer level without affecting the setting of the system.
A thermostatic mixing valve is more responsive in its regulation but does much the same. Proper installation and adjustment are essential; these are no ordinary tap fittings and a screw turned because the shower is on the chilly side can be a safety hazard.
It is a mistake to think that a 60°C reading at the tank means all the taps ought to be 60°C. They have different roles to play, one for hygiene of the stored water, the other for safe use.
Bathroom and Kitchen Readings
A test of a few outlets will show if the problem is house wide or confined to one part of the plumbing. Make a comparison of the laundry and kitchen sink with the bathroom tap under like conditions.
Do not be under the impression the shower is the same as the basin; mixers in a shower are often fitted with their own controls or flow restriction and will not behave in the same way. Measuring at the shower is not easy so put the thermometer out of reach of your feet and use a container you can rely on not to tip over.
Home Checklist
- A digital, probe or food thermometer will do.
- Let the hot water run 30 to 60 seconds at each tap before you put down the result.
- Test the bathroom, kitchen and laundry taps separately.
- Put children and pets aside for the testing.
- Make a note of any odd smells or noises, pressure variations or sizeable temperature differences.
There is no need to go to any lengths with this plan of access. Simply clear the space around the tap and have a stable surface for the container so you can shut the water off in a hurry. In a tight laundry or a damp bathroom sensible footwear with grip is in order and electricals should be well clear of any splashing.
Interpreting the Results
One reading is fine but a pattern is preferable. Do it twice at each outlet with a short cool down in between. Consistent results would suggest the system is in order. A big difference points to something amiss with the tap, mixer or branch pipe.
Take a bathroom tap at 57°C and a kitchen sink at 49°C for instance, there could be an issue with the valve or mixer in the bathroom. Should every outlet be 57°C and up, the tempering valve is in question. Below par across the board and the heating element, gas burner or thermostat may want some attention.
| Test Result | Possible Meaning | What to do |
|---|---|---|
| One outlet is running much hotter | Problem with local pipework, valve or mixer | Get a licensed plumber to inspect. |
| All outlets are too hot | Control or tempering valve problem | Do not consider the water safe, get professional input. |
| All outlets are on the cool side | Storage, thermostat or heating issue | An assessment of the hot water system is in order. |
| Sharp fluctuations in temperature | Something wrong with the system control or flow | Refrain from using the outlet in question until it has been seen to. |
One should be mindful of the difference between what is expected and what one gets in reality. The tap will not always come up to temperature in an instant and the initial reading could be water from the pipe. But a case of water going from comfortable to scalding is more than “the way old houses are”, it is a matter of safety.
Water That Feels Wrong Needs Fixing
Should the hot water be too hot, put the outlet out of service until you have gauged the risk. Make sure other members of the household are made aware of it, children and visitors in particular. Leave any adjustments to the tempering valve or hot water thermostat to those with the qualifications for it.
Conversely, do not be hasty in turning up the system if the water is underwhelming. A low figure might be due to excessive demand, an insulation issue or a defective burner, valve, heating element or thermostat. To raise the setting without first inspecting the controls is to invite the possibility of scalding water in some part of the house.
When To Cease Your Testing
There is no substitute for a licensed plumber if temperatures are erratic or readings are at variance with what they should be, or where a tempering valve is in question. One would also be wise to seek professional assistance following any alterations to the plumbing, a new hot water system or a shift in the demands of the household.
And call a plumber without delay over discoloured water, gas odours, electrical problems, a pressure relief valve in poor shape or any unusual banging. Under no circumstances take the cover off an electric or gas hot water system to see what the thermostat is doing; there are live components, gas combustion and perilous heat involved.
As for the 2026 hot water regulations, how they are interpreted can differ by state and industry, so do not put too much stock in online summaries. A plumber will be able to look at the installation and tell you what your home is subject to.
Some Frequently Asked Questions on Temperature
After putting a thermometer to a tap or two, one is apt to start thinking the whole house is against them. Here are the answers to the questions I get most.
What Is the Temperature of Sydney Tap Water?
You will not find a typical hot tap temperature that applies to all of Sydney. What you get is dependent on recent use, the length of pipe, the outlet and your storage system and tempering valve. Put the tap on for 30 to 60 seconds to test it instead of going by some city-wide average.
How Hot Should the Kitchen Sink Be?
The norm for a domestic kitchen is for the outlet to be around 50°C, though Australian plumbing rules and the specifics of the installation dictate this. Have a professional look at it if the water is well above the mark or hurts to put a hand to.
Shower Temperature: How Do I Check?
A clean probe thermometer and a heat-resistant container that is steady will do. Run the shower for half a minute or so, making certain the thermometer does not touch the container and that no one is in the way. If the temperature is prone to sharp swings the mixer may have to be replaced or put right.
Can I Test the Thermostat?
Test at the tap if you like but unless you are qualified, keep your hands off the system and the thermostat. An appropriately credentialed technician or plumber is the one to check the controls, heating and safety devices.
Is 60°C Safe at the Tap?
Not as a rule for a household outlet; at 60°C you can be badly scalded. While stored water is kept at about that level, a tempering valve ought to bring the temperature down before it comes to the tap.
Make It a Habit
It is good practice to test the hot water from time to time, provided it is done with care. Record the numbers from a couple of outlets with a decent thermometer and consider any unaccountable heat a safety problem.
Do it after any work has been done on the plumbing, or when a child comes to live with you, or the water seems to have changed its character. It takes only a few minutes and can put a licensed plumber on to a problem quicker.
