20
Maintenance
6 Dependant upon the results obtained from the first two series of tests; there are a number of
possible outcomes:
6.1 If no significant change in the mixed water temperatures (e.g. ≤ 1˚K) is recorded
between commissioning and Maintenance sections 1 or between commissioning and
Maintenance sections 5, the next in service testing should be carried out at a period of
24 to 28 weeks after initial commissioning.
6.2 If a small change (e.g. 1 to 2˚K) in the mixed water temperature is recorded in only
one of these periods, necessitating adjustment of the mixed water temperature, then
the next in service can be deferred to 24 to 28 weeks after commissioning.
6.3 If small changes (e.g. 1 to 2˚K) in the mixed water temperature are recorded in both of
these periods, necessitating adjustment of the mixed water temperature, then the next
in service test can be deferred to 18 to 21 weeks after commissioning.
6.4 If significant changes (e.g. > 2˚K) in the mixed water temperature are recorded in both
of these periods necessitating service work, then the next in service test should be
carried out at 18 to 21 weeks after commissioning.
7 The general principle to be observed after the first 2 or 3 in-service tests is that the intervals
for future tests should be set to those which previous tests have shown can be achieved
with no more than a small change in mixed water temperature.
8 In all areas periodic maintenance of the valve and associated fittings i.e. strainers, check
valves will ensure optimum performance levels are maintained.
Spares
A full range of spares are available for this product from Twyford.
PLEASE NOTE:
Only genuine spares should be used.
Please leave this Manual for the User
installation guide
TMV3
