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Pipe Sizing / Materials / Push Fit
To achieve even distribution of the available supply of hot and cold water, it is
important in any mains pressure system, that the piping in a dwelling should be sized
in accordance with BS EN 806:1-5: BS EN 8558:2011. This is particularly important in
a large property with more than one bathroom.
However, the following rule of thumb guide lines should be adequate for most smaller
property types as long as water pressures are within the recommended range.
1. A 15mm copper or equivalent external service may be enough for a small 1
bathroom dwelling (depending upon the flow rate available), but the minimum
recommended size for new dwellings is 22mm (25mm MDPE).
2. The internal cold feed from the main incoming stop tap to the BoilerMate SP
should be run in 22mm pipe. The cold main and hot draw-off should also be run
in 22mm as far as the branch to the bath tap.
3. The final branches to the hand basins and sinks should be in 10mm and to the
baths and showers in 15mm (1-meter minimum).
4.
We would recommend that best results for a balanced system are achieved by
fitting appropriate flow regulators to each hot and cold outlet. This is particularly
relevant where the water pressures are above the recommended water pressure
range. Details of suitable flow regulators are provided in Appendix A.
All the recommendations with regard to pipework systems in this manual are generally
based on the use of BS/EN Standard copper pipework and fittings.
However, we are happy that plastic pipework systems can be used in place of copper
internally as long as the chosen system is recommended for use on domestic hot
and cold water systems by the manufacturer and is installed fully in accordance with
their recommendations. This is particularly important in relation to use of push fit
connections when using the optional flexible hose kits - see installation section of
this manual.
It is also essential that if an alternative pipework material/system is chosen the
manufacturer confirms that the design criteria of the new system is at least equivalent
to the use of BS/EN Standard copper pipework and fittings.
Secondary circulation
If the length of the hot water draw off pipework is excessive and the delivery time
will be more than 60 seconds before hot water is available at the tap, you may wish to
consider using trace heating to the hot water pipework such as the Raychem HWAT
system. Also, a conventional pumped secondary circulation system (shown below)
can be used with any model of the BoilerMate SP.
INSTALLATION
DOMESTIC HOT WATER
BoilerMate
Inline filter &
flow regulator
Single check
valve
Single
check
valve
Pump isolation
valves
Cold water inlet
Plate heat exchanger
Hot water outlets
Pipework length and
diameter to suit
property demands
Pipework length and
diameter to suit
recirculation flow rate
approx 1-2 l/min
Cold water sensor
Control
stat
Flow switch
Potable water
expansion vessel
Secondary
circulation
pump
A pipe thermostat is incorporated in the circuitry which cuts the supply to the pump
when the water in the return pipe reaches the set temperature. Ensure the hot water
temperature is set correctly to avoid excessively hot water at the outlets and long
pump run times.
Secondary circulation pipework must be
insulated to prevent energy loss in both heated
and unheated areas.
Bath Hot Water Temperature
Bath hot water supplies should be limited to a
maximum of 48°C using an inline blending valve.
Pipe Separation
It is important that the cold-water pipework
is adequately separated/protected from any
heating/hot water pipework to ensure that the
water remains cold and of drinking water quality.
Tap outlets
Aerated taps are recommended to prevent
splashing.
Showers
Any type of shower mixing valve can be used
as long as both the hot and cold supplies
are mains fed. However, all mains pressure
systems are subject to dynamic changes
particularly when other hot and cold taps/
showers are opened and closed, which will
cause changes in the water temperature at
mixed water outlets such as showers. For
this reason and because these are now no
more expensive than a manual shower we
strongly recommend the use of thermostatic
showers with this appliance.
The shower
head provided must also be suitable for
mains pressure supplies.
However, if it is proposed to use a ‘whole body’
or similar shower with a number of high flow/
pressure outlets please discuss with the Gledhill
technical department.
Shower Pipework
The hot water supply to a shower-mixing valve
should be fed wherever practical directly from
the BoilerMate SP or be the first draw off point
on the hot circuit. The cold supply to a shower-
mixing valve should wherever practical be fed
directly from the rising mains via an independent
branch. The shower must incorporate or be fitted
with the necessary check valves to provide back-
siphonage protection in accordance with the
Water Regulations.
Bidet Supply
The supply of hot and cold mains water directly
to a bidet is permitted provided that it is of the
over-rim flushing type and that a type ‘A’ air gap
is incorporated.
Содержание BOILERMATE OV PP
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