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TMV Mixing Valves

Thermostatic Mixing Valves – TMV Valves

Thermostatic mixing valves or TMV valve is a mechanical device installed on hot and cold water supply pipework upstream of wash hand basins, sinks, baths and shower units. The TMV valve mixes the hot water usually at 60°c and the cold water down to a safe desired tap outlet temperatures typically between 39°c and 43°c

The installer or maintenance engineer sets the outlet temperature using the thermal cartridge within the valve body which is blended using the wax capsule and piston. Most TMV valves have a safety shut down in the event of the loss of the cold water supply to prevent the outlet temperature becoming too hot and scalding the user


Its very important to have TMV valves fitted where vulnerable users of the hot water basins, sinks, baths and showers. People with a reduced ability or sense may not perceive risk which may result in scalds.  Young children and older people have thinner skin and can scald much easier.

Below is a the exposure times for partial thickness burns from hot water

Should TMV valves be maintained?

Yes.  It’s a requirement of BuildCert TMV2 Scheme that all TMV2 approved valves shall be verified against the original set temperature result once a year. Its also forms part of the L8 obligations and for health care, HTM04-01 requirements

So regular in service maintenance tests are required especially for schools, care homes and health service properties.

Evans Maintenance service, maintain and repair or replace TMV mixing valves in many properties using calibrated digital thermometers.  We calibrate the outlet temperature to the desired temperature, clean and flush the non-return valves and check their operation. We also check where fitted the safety slam shut functionality of the valve

Areas We Cover

Anglesey Caernarfon Cheshire Chester | Deeside | Llandudno Llangollen North Wales | Powis Rhyl Shrewsbury Shropshire Warrington Wirral Wrexham

Why not give us a call and we can discuss your requirements or if you would like to schedule and engineers visit

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