Valves
Pipework Systems 
Housing Associations should check need for thermostatic mixing valves to prevent scalding, says Honeywell
Housing associations should act now to
ensure residents cannot be scalded by hot water, warns
Honeywell, the leading manufacturer of water valves and heating
controls. Regulations require that housing associations fit a
thermostatic mixing valve (TMV), which ensures scalding water
cannot be provided at the point of delivery, on showers, baths
and basins in dwellings for the elderly. In other dwellings,
associations should fit TMVs on baths and basins to comply with
Best Practice. The new scale-resistant Honeywell TM300,
certified to the new Buildcert TMV2 scheme, is acceptable in all
premises except those subject to the Care Homes Regulations
because they are used by the severely disabled; these require a
valve such as the Honeywell TM200VP, rated to the higher TMV3
standard.
The TM300 is scale-resistant and designed for “under-bath”
installation on both high and low pressure systems. It is one of
very few TMV2 valves certified for use with the full range of
bathroom appliances: bidets, showers, washbasins and bathtubs.
It employs a highly sensitive wax element which controls the hot
and cold water inlets to provide a safe uniform temperature
between 38 and 46 degrees C, as set by the installer. In
addition, it ensures safety by cutting off the hot water inlet
automatically if the cold supply fails.
Honeywell explains that the BuildCert TMV scheme recommends the
following maximum hot water temperatures for use in all
premises: 46 degrees C for bath fill; 41 degrees for showers and
washbasins; and 38 degrees C for bidets. However, while 46
degrees C is the maximum temperature for water from the bath hot
tap, it takes into account the margin of error inherent in TMV2
valves and temperature loss in metal baths, especially in cold
bathrooms. It is not a safe bathing temperature for adults or
children. The British Burns Association recommends 37 to 37.5
degrees C as a comfortable bathing temperature for children.
For more advice on regulating maximum hot water temperatures,
see Housing Corporation Standards 1.2.1.33a (general dwellings)
and 1.2.1.58 and 1.2.1.69 (dwellings for the elderly).
For details of Honeywell water control products call freephone
0800 7833 824, e-mail water.control@honeywell.com or write to:
Water Products, Honeywell Control Systems Ltd., Honeywell House,
Arlington Business Park, Bracknell, Berkshire RG12 1EB.
Email:
HVACProductsUK@honeywell.com