User guide

22
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 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 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 supply 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 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 in the Maintenance section.
The installation of thermostatic mixing
valves must comply with the requirements
of the Water Supply (Water Fittings)
Regulations 1999.