Section 4: installation information
Page 12
4.1 Boiler Location
The Grant External Vecta wood pellet boiler must be installed
externally, either against the building or ‘free standing’ some distance
away from the building. Refer to Section 7.7.
If the ‘free standing’ option is chosen, then the boiler flue system must
be at least 2,300mm away from any buildings or structure that are
higher than the flue outlet. Refer to Section 7.7.
If this distance cannot be achieved, then the External Vecta boiler will
have to be located with the back of the enclosure close to or against
the building and the flue system extended such that the terminal is
above the eaves of the roof. Refer to Section 7.7.
The Grant External Vecta boiler must be positioned such that
sufficient clearance is provided for maintenance, servicing and filling
the pellet hopper. In the particular, the following minimum clearances
are required around the External Vecta:
•
Front: 850mm (to open the hinged front door to commission or
service the boiler)
•
Left hand side: 400mm (to access the PCB, water and
condensate connections)
•
Right hand side: 150mm (to access pellet hopper for filling with
pellets)
•
Rear: 30mm
The Grant External Vecta boiler must stand on a solid, level, non-
combustible surface capable of supporting both the weight of the
boiler when full of water and the pellet hopper is full of pellets. Refer to
Section 2 for weights.
Grant recommends a prepared concrete standing (at least 150mm
thick) with a smooth finish on the top extending beyond the enclosure
base at least 100mm all around. Refer to Section 2.4 for boiler
dimensions.
4.2 Regulations
Installation of a Grant Vecta wood pellet boiler must be in accordance
with the following:
•
National Building Regulations and any local Byelaws.
•
Model Byelaws and the Water Supply Regulations.
The installation should also be in accordance with the latest edition of
the following standards and codes of Practice:
•
BS 715:2005 Metal flue pipes, fittings, terminals and accessories.
•
BS EN 12828:2003. Heating systems in buildings. Design for
water-based heating systems
•
BS EN 12831:2003. Heating systems in buildings. Method for
calculation of the design heat load.
•
BS EN 14336: 2004. Heating systems in buildings. Installation
and commissioning of water based heating systems.
•
BS 7593:2006 Code of Practice for treatment of water in heating
systems.
•
BS 7671:2008 Requirements for electrical installations, IET wiring
regulations.
•
ONORM M7137 standard should be used as a guideline for DIY
bulk storage units.
Failure to install and commission the appliance correctly will
invalidate the boiler guarantee.
nOtE
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4 installation information
4.3 Heating System
Before starting any work on the boiler or fuel supply please
read the Health & Safety information given in Section 17.
!
WaRninG
To achieve the maximum efficiency possible from the Grant Vecta
condensing wood pellet boiler, the heating system should be
designed to the following parameters:
Radiators
•
Flow temperature 70°C
•
Return temperature 50°C
•
Differential 20°C
Size the radiators using a mean water temperature of 60°C.
Design system controls with programmable room thermostats, or
use weather compensating controls, to maintain return temperatures
below 55°C.
the boiler should not be allowed to operate with a return
temperature of less than 40°C when the system is up to
operating temperature.
nOtE
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The use of a pipe thermostat is recommended to control the return
water temperature when using weather compensating controls.
Underfloor Heating
• Flow temperature 50°C
• Return temperature 40°C
• Differential 10°C
In underfloor systems it is essential that the return temperature must
be maintained at or above 40°C to prevent internal corrosion of the
boiler water ‘primary’ jacket.
Open Vented Systems
the presence of ‘pumping over’ in an open vented heating
system connected to the Grant Vecta boiler will invalidate the
product guarantee.
nOtE
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Open vented systems must be correctly designed and installed.
The open safety vent pipe must be positioned to prevent ‘pumping
over’ (i.e. the discharge of water from the open safety vent pipe into
the feed and expansion cistern under the pressure created by the
circulator).
For detailed information on the correct design of open vented heating
systems, and the correct location of the open safety vent pipe, refer to
the CIBSE Domestic Heating Design Guide.
