A Thermostatic Mixing Valve (sometimes called a TMV) is a valve that blends hot water with cold water to produce an even temperature thus ensuring there is constantly safe outlet temperature, preventing scalding.

Thermostatic Mixing Valves are used to protect people especially customers, the elderly, people with a disabilities and young children, from the scalding effects of water that is too hot. They also reduce the risk of disease spreading in your water supply as hot and cold is mixed at the right temperature just prior to coming out of the tap.

An extremely important function of a TMV is if the supply of cold or hot water is lost, the water flow will shut down immediately, preventing scalding, burning and dangerous reactions from moving too quickly away from a too hot or too cold water stream resulting in injury.

Approximate contact times to receive a third-degree burn:

  • At 70°C – 1/sec adult – 0.5/sec child
  • At 60°C – 5/sec adult – 1/sec child
  • At 55°C – 30/sec adult – 7/sec child
  • Below 50°C – approx. 5 mins adult/child

Due to the potential for serious burns at 60°C, there is a compliance requirement to ensure a safer temperature at the tap. AS3498 is the standard used for TMV installation and testing and it requires the delivery of hot water for personal hygiene to be delivered from the tap at a maximum of 50°C to prevent burns. For early childhood centres, schools, aged care, corporate facilities or other specific businesses with customers at risk like hairdressers or beauty salons the maximum temperature at the tap must be 45°C.

At Watertight Group we provide correct installation, maintenance and annual testing of your Thermostatic Mixing Valves (TMVs) to ensure that they are operating correctly, protecting you, your business and your customers and staff. Our highly experienced team are qualified to service and carry out an annual TMV testing and maintenance program on all forms of TMV’s.

In many industries including aged care facilities, installation and yearly certification of thermostatic valves is a compliance and legal requirement. The TMV Testing Requirements according to the Australian Standard (AS4032.3) states that a TMV shall be inspected and maintained at least every 12 months and the replacement of thermostat and o-rings every 5 years. NSW Health Act 2010 requires hospitals to test TMV’s every 6 months to ensure scald prevention.

Book Watertight Group today for these facilities:

  • Hospitals and medical centres
  • Hairdressing and beauty salons
  • Disabled amenities/facilities
  • Childcare and early learning centres
  • Aged care and retirement facilities

Our expert plumbers and tailored scheduled maintenance programs keep your operations running as efficiently and smoothly as possible and prevent small and large scale problems from occurring, saving you unnecessary insurance claims, lost productivity and safety issues. We can work around your patients, guests, customers, students and staff to ensure your facility is not affected by any down time from our works. Watertight Group provide these services across all areas including: Sydney CBD, Greater Sydney areas, Illawarra region, ACT, Goulburn, Central Coast and other regional NSW areas).

Testing and maintenance program

Contact us today to create a specific annual TMV testing and maintenance program for your business. We can provide you with a location or condition asset audit. We can GPS where all your valves are located. As part of our quality guarantee you will never have to worry about forgetting your test again. Watertight Group will send you a reminder for testing and arrange a convenient time to carry out testing ensuring we do not hold up the productivity of your business, school, entertainment, health, aged care or corporate facility.

For more information on TMV testing and maintenance, get in touch with our professional team by calling 1300 745 758 


Andrew W, Property Manager


Canterbury Bankstown Business Chamber Corporate Member

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