andrews Flexistor 1000, Installation Manual

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13
Installation & Commissioning
General installation
Pipe fittings
All pipe connections to the Andrews Flexistor are made via BSP female parallel threaded pipe
connection directly to the unit.
Cold water supply
A 2”cold water supply is recommended, however, if a smaller supply exists which provides
sufficient flow this may be used. More flow noise may be experienced from small bore pipes due
to the increased water velocity through them. A minimum flow rate of 100l/min is required for the
Andrews Flexistor range of cylinders
High flow cold water control pack (Low and high pressure)
The control pack consists of a pressure reducing valve with integral strainer, check valve, core
unit and expansion relief valve. The pressure settings are adjustable for the low or high pressure
valve sets. For the“low” pressure valve set the pressure reducing valve can be set between 1.5
and 6 bar. For the “high” pressure valve set the pressure can be set between 5 and 10 bar. For
optimum performance the following installation instructions should be complied with.
Note: The expansion vessel pressure must be set in accordance with the inlet pressure set on the
pressure reducing valve by the installer. Set the Expansion Vessel pressure before pressurising
the cylinder.
Installation
Flush supply pipe work before connection to remove all flux and debris prior to fitting the inlet
controls. Failure to do this may result in irreparable damage to the controls and will invalidate the
warranty.
The pressure reducing valve can be fitted in any orientation to suit the installation as long as it is
fitted in the correct flow direction. Check the flow arrows on the side of the body.
The expansion relief valve should be installed with the discharge pipe work in either the horizontal
position or facing downwards, if the discharge pipe is facing upwards debris may be deposited on
the seat of the valve when in operation.
The blank plastic plugs in the body of the pressure relief valve are pressure gauge connections to
enable pressure monitoring to be carried out, should the system develop a fault. It is recommended
that these be accessible (the pressure reducing valve has two – only one need be accessible).
Expansion relief discharge pipe work must be connected to a safe visible discharge point via a
tundish and the pipe work must have a continuous fall. If site conditions allow, the expansion relief
discharge pipe work can be connected to the T&P valve discharge pipe work before the tundish.
Pressure reducing valve
The pressure reducing valve can be connected anywhere on the cold water mains supply prior
to the Andrews Flexistor unit. There is no requirement to site it close to the unit, it can be located
at a point where the mains supply enters the premises if this is more convenient but you must
install a non-return valve just after the reducing valve for ease of maintenance. The pressure
reducing valve incorporates a adjustable pressure reducer / strainer. The valve can be fitted in
any orientation to suit the installation, however, ensure that the valve is installed with the direction
of flow arrows (stamped on the side of the brass body) pointing towards the Andrews Flexistor
cylinder