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temperature takes account of the allowable
temperature tolerances inherent in thermostatic
mixing valves and temperature losses in metal
baths.
It is not a safe bathing temperature for adults
or children.
The British Burns Association recommends 37
to 37.5°C as a comfortable bathing temperature
for children. In premises covered by the Care
Standards Act 2000, the maximum mixed water
outlet temperature is 43°C.
The thermostatic mixing valve will be installed in
such a position that maintenance of the TMV and
its valves and the commissioning and testing of
the TMV can be undertaken.
The fitting of isolation valves is required as close
as practicable to the water supply inlets of the
thermostatic mixing valve.
Commissioning notes for Thermostatic Mixing
Valves
The first step in commissioning a thermostatic
mixing valve is to check the following:
The designation of the thermostatic mixing valve
matches the application.
The supply pressures are within the valves
operating range.
The supply temperatures are within the valves
operating valve.
Isolating valves (and strainers preferred) are
provided.
If all of these conditions are met, proceed to
set the temperature as specified in section:
‘Commissioning’
.
Important!
The mixed water temperature at the
discharge point must never exceed 46°C
It is a requirement that all TMV2 approved
valves shall be verified against the original
set temperature results once a year. When
commissioning/testing is due the following
performance checks shall be carried out.
Measure the mixed water temperature at the
outlet.
Carry out the cold water supply isolation test by
isolating the cold water to the TMV, wait for five
seconds if water is still flowing check that the
temperature is below 46°C.
If there is no significant change to the set outlet
temperature (±2°C or less change from the
original settings) and the fail-safe shut off is
functioning, then the valve is working correctly
and no further service work is required.
Notes!
If there is a residual flow during the
commissioning of the valve or the annual
verification (cold water supply isolation test), then
this is acceptable providing the temperature of
the water seeping from the valve is no more than
2°C above the designated maximum mixed water
outlet temperature setting of the valve.
Temperature readings should be taken at the
normal flow rate after allowing for the system to
stabilise.
The sensing part of the thermometer probe
must be fully submerged in the water that is to
be tested.
Any TMV that has been adjusted or serviced must
be re-commissioned and re-tested in accordance
with the instructions given in this guide.
The installation of thermostatic mixing valves must
comply with the requirements of the Water Supply
(Water Fittings) Regulations 1999.
Summary of Contents for Miniduo
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