The relief valve will open when the pressure exceeds a pre set valve. If the valve is opening when it is not expected to it may have failed and need to be replaced.  Always check the water system  pressure before replacing the valve.

Thermostaticmixing valvetemperature setting

Pressure and Temperature Relief (P & T Relief) Valves are safety controls which ensure that the temperature of the water in a pressurised unvented water heater cannot exceed 99° C in the event that the normal thermostatic controls fail.

ThermostaticMixing Valve15mm

These valves may be used to guard against over-temperature and over-pressure hazards wherever water is stored in unvented containers. This is a requirement of Australian Standard AS 3500-4.

ThermostaticMixing Valvetap

Use the Resideo Pro App to install T6 Pro Smart Thermostat in homes, which will associate those homes to your company. Then you'll be able to select which homeowners see your logo based on the pricing per household (consumer will not be charged).

The AM100 series of mixing valves from Resideo accurately adjust, maintain, and limit the hot water temperature to a desired setting selected by the user. More usable hot water is available with a AM-1 mixing valve from Resideo, as it raises the water heater storage temperature setting and limits mixed outlet water temperature to a safe level.