Installation; Suitable Plumbing Systems; General - Mira Select Flex Installation And User Manual

inStallation

Suitable Plumbing Systems

Gravity Fed:
the thermostatic mixer must be fed from a cold
water cistern (usually fitted in the loft space) and
a hot water cylinder (usually fitted in the airing
cupboard) providing nominally equal pressures.
Mains Pressurised Instantaneous Hot Water
System (Combination Boiler):
the thermostatic mixer can be installed with
systems of this type with balanced pressures.
(recommended Minimum Maintained Pressure:
1.0 Bar).
Unvented Mains Pressure System:
the thermostatic mixer can be installed with an
unvented, stored hot water system.
Pumped System:
the thermostatic mixer can be installed with an
inlet pump (twin impeller). The pump must be
installed in a suitable location and in accordance
with its instructions.

General

installation must be carried out in accordance
with these instructions, and must be conducted by
designated, qualified and competent personnel.
the installation must comply with the "Water
Supply Regulations 1999 (Water Fittings)" or any
particular regulations and practices, specified by
the local water company or water undertakers.
Note! Make sure that all site requirements
correspond to the information given in section:
'Specifications'. For type 2 and type 3 Valves
see also supply conditions in section: 'Type 2 and
Type 3 Valves'.
1. the mixer must not be installed in an area
where it may freeze.
2. For stud partitions alternative fixings may be
required.
3. 'Full bore' isolating valves must be installed
close to the mixer for ease of maintenance.
4. Pipework must be rigidly supported and avoid
any strain on the connections.
5. Pipework dead-legs should be kept to a
minimum.
6. decide on a suitable position for the mixer.
the position of the mixer and the shower
fittings must provide a minimum gap of 25 mm
between the spill-over level of the shower tray/
bath and the showerhead (refer to illustration).
this is to prevent back-siphonage. For further
information on the installation of your shower
fittings, refer to the fittings installation and
user guide.
Note! Only use shower fittings recommended
by the manufacturer or supplier.
hose retaining ring
Important! a hose retaining ring should be
fitted to prevent the showerhead from dropping
below the spillover level of the shower tray/
bath, which could lead to contamination from
back-siphonage. this hose retaining ring
should meet the majority of user requirements
for shower installations with flexible outlet
fittings. however, there will be occasions
when the hose retaining ring will not provide a
suitable solution. in these instances an outlet
double checkvalve, e.g. the Mira dcV-h, must
be fitted. The inclusion of the Mira DCV-H
will increase the required supply pressure
typically by 10 kPa (0.1 bar), refer to section:
'Accessories'.
7
25 mm Minimum
Spill-over
level