Thermostatic Mixing Valve (TMV)

What is Thermostatic Mixing Valve work?

Get to know the regulation

Under Part 5 of the Plumbing Regulations 2018, Thermostatic Mixing Valve work is the repair, alteration, maintenance and testing of a thermostatic mixing valve.

Thermostatic Mixing Valve work does not include:

  • (a) the construction, installation, replacement or commissioning of a thermostatic mixing valve.
  • (b) the construction, installation, replacement, repair, alteration, maintenance, testing or commissioning of a tempering valve.

What competencies and experience do you need?


To be eligible to apply for registration in Thermostatic Mixing Valve (TMV) work, you must:

  1. Already be registered or licenced in the class of Water supply work, and
  2. Have completed the unit of competency: Commission and maintain hot and heated water temperature control devices (CPCPWT4023A or CPCPWT4023), and
  3. Successfully complete the VBA exam for this class
    • If you have successfully completed the prescribed unit listed above at Master Plumbers in 2014 or later, you most likely have already completed the VBA exam and do not need to sit it again if you have.


To be eligible to become licenced in this class, you must be:

  • Licenced in the class of Water supply work, and
  • Eligible to hold or currently hold registration in this class.