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PLANNeD MAINTeNANCe
Malfunction of the DMV is almost always progressive in nature and will be detected
by the use of proper temperature checking and maintenance routines.
Certain types of system can result in the DMV having excessive ‘dead-legs’ of
pipework, or auxiliary cold water supply added to the mixed water from the mixing
valve. Such systems can disguise the onset of thermostatic mixing valve malfunction
and should not be used.
We recommend a preventative maintenance procedure based on site conditions
and the risk to the user. All results must be recorded in a log book.
Healthcare
Healthcare applications are hospitals, aged person facilities, residential care homes,
etc. and any other applications where the user is similarly at risk.
Ultimately, the user or attendant must exercise diligence to make sure that the delivery
of warm water is at a stable, safe temperature. This is particularly important in such
procedures as supervised bathing where patients are unable to respond immediately
to unsafe temperatures.
Irrespective of supply and usage conditions or the evidence of in-service tests, the
critical components listed in the table below, should be replaced at intervals of no
more than 5 years.
Note!
During the replacement of critical components, it may be necessary to replace
other non-critical components.
Critical Components
Pack Number
Description
463.31
DMV Solenoid manifold (Open)
463.07
Thermistor pack