4
Hoval STU Wood Pellet Boiler
Installation and Use.
The installation of the boiler and stoker must be in accordance with the relevant British Standards, I.E.E. Regulations and the by laws of
both the Local Authority and the local Water Authorities.
A flat level fire proof floor should be provided - the location should permit the provision of a satisfactory flue system and adequate air supply.
The STU Wood Pellet Boiler is designed and approved for use as a heat generator for hot water heating systems with flow temperatures
up to 85°C and a maximum working pressure of 3 bar. The boilers have been tested and certified by TÜV and they comply with the
requirements of the European standard for boilers for solid fuels BS EN 303-5 (Note: BS EN 303-5 is limited to boilers with outputs of
300kW or less, however for outputs exceeding 300kW the boilers are tested using the procedures as set out in BS EN 303-5 and fully
meet the required standard). The STU boiler has an automated pellet delivery system and is not designed for "hand" or manual feeding
of wood pellets under any circumstances.
Sample nameplate
Hoval Limited, Northgate Newark. Notts NG24 1JN
Tel: 01636 672711 Fax: 01636 673532
Boiler Model :
STU WOOD PELLET
Type :
STU 200
Serial No :
K
Year of Manufacture :
2010
Output (wood pellets) :
200 kW
Input (wood pellets) :
253 kW
Maximum Heat Output :
200 kW
Flue Temp (wood pellets) :
180
o
C
Operating Temperature : Min 60 Deg C Max 90 Deg C
Working Pressure :
3.00 bar
Test Pressure :
5.55 bar
Water Content :
824 Litres
Electrical Connection :
3ph / 50Hz / 400V
This appliance must be installed in accordance with the rules in force and used
only in a sufficiently ventilated space. Consult instructions before installation and
use of this appliance.
Fuel Quality Requirement
The design of the boiler, stoker, pellet handling system and store is dependant on using the correct quality wood pellet fuel.
The pellets should be formed from clean or virgin timber where they are held together with the natural resin and binders (or lignin) in the
wood fuel. The fuel MUST NOT contain halogenated organic compounds or heavy metals as a result of treatment with wood preservatives
or coating.
Specifications of wood biomass fuels can be found at BS EN303-5 Table 8 Test fuels.
Compressed wood (C) and / or CEN/TS14961, Solid biofuels Fuel specifications and classes.
Hoval suggests that the following fuel specification (As Recieved) for use on the STU wood pellet boiler,
Calorific Value net basis CV:
Minimum 17,000 kJ/kg (4.72 kWh/kg).
Moisture Content M10:
Moisture Content is no more than 10%.
Ash Content A1.0
Ash Content is no more than 1%.
Size D06
:
Pellet Diameter either 6mm preferred (8mm may be acceptable).
Pellet Length:
Typical pellet length 20-30mm.
Fines Content F1.0:
As Loaded into Delivery Vehicle Fines (-3mm material) no more then 1%.
Sulphur S0.05:
Sulphur Content no more than 0.05%.
Mechanical Durability DU97.5:
Fuel Delivery
Wood Pellet fuel to be delivered by specialist vehicle as utilised by the appointed fuel supplier to site. Fuel delivery via bulk blower vehicles
fitted with suitable low-pressure blowers. Hoval do not recommend or endorse any particular fuel supplier or manufacturer however it is
recommended that fuel is ALWAYS supplied against a specification and the supplier concerned operates well maintained vehicles and
fully trained delivery drivers to ensure that the boiler and fuel transfer system are presented with well sized wood pellets that are free
from any contamination.
A nameplate will be attached to one of the side casing panels
of the boiler. This plate includes the serial number identifying
the boiler.
