Mira Montpellier Installation, Operation, Maintenance Manual page 23

2. Thermostatic mixing valves only operate correctly when all components have
been serviced and have been tested for correct performance. If any component
is faulty, including the thermostat the valve will not operate correctly and
could allow full hot water to pass through the valve.
3. As with all other thermostatic mixing valves, the critical sensing element in
the Mira Crescent together with other "critical components" are contained
within the service free cartridge and will exhibit wear over a period of time and
usage.
Thermostatic Mixing Valve Performance Records
It is recommended that the user maintains a log of the in-service tests described herein,
together with a record of any service work carried out and the replacement of critical
components. It is also recommended that any maintenance personnel sign the user
log in respect of all thermostatic mixing valves examined on each attendance at the
user's premises. Refer to 'Recommended content of Maintenance Log' on page
30.
The designed minimum service life of cartridges used in all Mira products is 5 years
providing the Mira Montpellier is operated with the recommended operating conditions
and within the recommended operating parameters. However, when supply conditions
and/or usage patterns do not conform to the recommended operating parameters
and/or the recommended operating conditions, the cartridge and other critical parts
may need to be replaced more frequently ('recommended operating conditions' and
'recommended parameters' are defined on page 7 of this Product Manual under the
headings of 'Normal Operating Conditions' and 'Operating Parameters').
Important! In healthcare applications such as hospitals, aged person facilities,
residential care homes, etc. and in any other applications where the user is similarly
at risk, irrespective of supply and usage conditions or the evidence of in-service
tests, the critical components should be replaced at intervals of no more than 3
years.
Performance Check
Six Monthly
Exercising the Thermostat: If the valve has not been in regular or recent use the
thermostat should be exercised before any other checking. When user adjustment
of the blend temperature is available the exercising of the thermostat can be achieved
as described in COMMISSIONING. For valves with locked temperature control it
is necessary to isolate and restore each supply in turn a few times.
Blend Temperature: check for correct blend setting and/or maximum preset
temperature. Reset as necessary.
23
(Log Book)