Commissioning
Commissioning notes for
Thermostatic Mixing Valves
The first step in commissioning a
thermostatic mixing valve is to check
the following:
1. The designation of the thermostatic
mixing valve matches the intended
application.
2. The supply pressures are within the
valves operating range.
3. The supply temperatures are within the
valves operating range.
4. Isolating valves (and strainers preferred)
are provided.
If all these conditions are met, proceed to
set the temperature as stipulated in the
maintenance section.
The mixed water temperature at the
terminal fitting must never exceed 46ºC.
It is a requirement that all 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 supply to
the TMV wait for five seconds, if water is
still flowing check that the temperature
is below 46ºC.
If there is no significant change to the set
outlet temperature (+/-2ºC 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 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
that 2ºC 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 in the
maintenance section.
The installation of thermostatic mixing
valves must comply with the requirements
of the Water Supply (Water Fittings)
Regulations 1999.
20
Need help? Give us a call on 0844 701 6273 and speak to one of our trained advisors.
