Worcester Greenstar Heatslave 12/18 Technical Information page 16

Plastic pipework
Plastic pipework must have a polymeric barrier.
Underfloor heating
•
Plastic pipework used for underfloor heating must be
correctly controlled with a thermostatic blending valve
limiting the temperature of the circuits to approx. 50ºC.
The pipework from the boiler to the blending valve must
be in copper or steel (protected from corrosion) if used in
a sealed primary water system.
Open vent systems and sealed systems
•
A minimum length of 1,000mm of copper or steel pipe
must be connected to the boiler after which plastic pipe
can be used.
Primary system/connections/valves
•
Do not use galvanised pipes or radiators.
•
All system connections, taps and mixing valves must be
capable of sustaining a pressure up to 3bar.
•
Radiator valves should conform to BS 2767:10.
•
All other valves should conform to BS 1010.
•
On new installations TRVs must be used on all radiators
except the radiator where the room thermostat is sited,
this must be fitted with lockshield valves and left open. All
boiler replacement installations should have TRVs fitted to
radiators at least within the sleeping accommodation.
•
Drain cocks are required at all the lowest points
on the system.
•
Air vents are required at all the high points
on the system.
Domestic water supply
Water Authority requirements
A direct mains water connection is accepted by Water
Authorities. However, it is recommended that reference
should be made to local requirements. In the event of any
difficulty contact the Worcester Technical Services
Department.
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Pipe sizing
An incoming cold water mains supply with a minimum 15mm
diameter is required. A 22mm copper hot water distribution
pipe to the first branch is recommended: thereafter 15mm
and/or 10mm to all draw off points. To achieve design flow
rates a minimum inlet working pressure of 1.5bar (12/18
model), 1.2bar (18/25 model) and 0.9bar (25/32 model)
is required.
Mains water connection
The cold water supply connection and general plumbing
layout should be in accordance with that shown in the
"System Layout" diagram on page 6. There should be no
device capable of preventing back flow of expansion water
unless separate arrangements for expansion water are made.
Wherever possible, the cold water supply to the appliance
should be the first tapping off the mains supply, in order to
minimise hot water flow reduction when cold services are
operated. The final 600mm of piping to the appliance should
be of copper only.
Flow balancing
As with all mains fed systems, the flow rate of water
obtainable from individual taps will vary in relation to the
number of taps operated simultaneously, and will depend
upon the cold mains supply to the property. Flow balancing
by the use of proprietary constant volume flow regulators or
'Ball-o-Fix' type valves may be required to avoid excessive
starvation of flow to individual taps.
Taps and water
Standard hot and cold taps and mixing valves to be used with
the appliance must be suitable for operating at mains
pressure. The use of lever operated taps being particularly
appropriate. In certain circumstances, anti-syphonage
arrangements will be necessary.
Shower
When a loose head shower with flexible hose is used over a
bath the hose must be fixed so that the head cannot fall
closer than 25mm above the top edge of the bath in order to
prevent the head from being immersed in the bath water.
Alternatively, the shower should incorporate or be fitted with
a double check valve at the point of flexible hose connection.
With fixed head showers no provision is necessary. The use of
a thermostatically controlled shower valve will give added
comfort and reduce the fluctuation of the temperature of the
water.
Bidet
The supply of hot and cold mains water direct to a bidet is
permitted, provided that the bidet is of the over-rim flushing
type. The outlet(s) should be unable to have any temporary
hand held hose attached.
Use in hard water areas
Under normal circumstances protection against scale is not
necessary with the Greenstar Heatslave range. However, in
exceptionally hard water areas (where temporary hardness
exceeds 200ppm) it may be beneficial to seek the advice of
the local Water Authority.
Boiler manufacture
The Greenstar Heatslave appliance is manufactured at our
modern factory at Clay Cross in Chesterfield. Stringent
in-house quality control ensures that the Greenstar
Heatslave appliance meets the highest standards of quality
and performance.
Clearances and siting (kitchen models)
The boiler does not require a constructional hearth.
The boiler should however be positioned on a non-
permeable solid base. Care should be taken to ensure that
the appliance is level.
The following clearances should be left for servicing:
•
Above 300mm
•
In front 600mm
•
Sides 5mm
•
Below –
Note: When fitted beneath a worktop, the necessary access
for servicing the appliance from above can be achieved by
using a removable worktop.
For external models, refer to page 12.
Electricity supply
The electrical connection to the boiler must allow complete
isolation of the appliance, preferably via a double pole
isolator with a contact separation of 3mm in all poles
supplying the boiler and controls only. A 5 amp fuse should
be fitted in the mains supply. The installation must be in
accordance with the relevant requirements of the IEE
Wiring Regulations. External equipment operated at 230
volts should not be installed, serviced or repaired under
adverse weather conditions.
Oil tanks
Tanks – general
Tanks should be located in the most unobtrusive position
possible, however thought should always be given to the
needs of safety, filling, maintenance and if necessary the
provision of a head of oil above the burner.
Reference must be made to OFTEC – Technical Information
note T1/133 covering the risk assessment of environmental
damage being caused by spillage from oil storage tanks,
this assessment must be completed by an approved OFTEC
technician to establish the type of tank necessary.
There should be a minimum distance of 600mm from the
tank and any foliage intended as a screen.
Oil storage installations fall into three classes –
Class 1, Class 2 and Class 3.
Class 1 – are those installations where the boiler does not
exceed 45kW or oil storage does not exceed 3,500 litres,
these installations are covered in BS 5410 : Part 1 : 1997.
Class 2 – are those installations where the boiler exceeds
45kW or the oil storage exceeds 3,500 litres, these
installations are covered in BS 5410 : Part 2 : 1998.
Class 3 – Large buildings and places of public
entertainment or assembly.
In England, the control of pollution (oil storage) (England)
regulations 2001 apply to storage over 200 litres for non
domestic properties or for any installation over 3,500 litres.
These appliances would generally fall into Class 1. If the
installation falls into class 2 or 3, OFTEC Book Three and
technical information sheet T1/136 must be consulted.
Size of tank
It is recommended that the minimum size of tank for the
Greenstar Heatslave boiler is 2,000 litres. However this can
be adjusted accordingly to the customer's requirements.
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