BENSON OUHA 100, Инструкция по установке и эксплуатации

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BENSON OIL UNIT HEATER
9
For heaters with a rated input of more than
60 kW — 540 cm
2
plus for each kW of rated
input over the 60 kW threshold an additional
4.5 cm
2
High Level (Outlet)
For heaters with a rated input of less than
60 kW — 4.5 cm
2
per kW of heat input
For heaters with a rated input of more than
60 kW — 270 cm
2
plus for each kW of rated
input over the 60 kW threshold an additional
2.25 cm
2
Alternatively mechanical input (not extract)
ventilation may be used in association with
either mechanical or natural extract , and
with a ventilation flow rate of 3.24m
3
/h per
kW of total rated input
Where mechanical extract is used to
complement the above then the extract rate
shall be 2.06m
3
/h per kW of rated heat input
Mechanical ventilation systems where fitted
must be provided with safety interlocks to
prevent heater operation in case of air flow
failure
2.4.3 Ventilation Openings and Grilles
Ventilation openings and grilles must
communicate directly with the outside air, be
of negligible resistance and shall be sited so
that they cannot easily be blocked of flooded
3.0 Fuel
The heaters are set for single pipe operation
The bypass plug is provided separate with
the burner for conversion to two pipe see
Riello manual
Three methods of fuel supply can be used to
supply fuel to the heaters
(a) Two pipe system
(b) Gravity Feed
(c) Pressurised ring main
Two pipe system
This is used where the oil storage tank is
lower than the pump.
Access for the fuel feed to the burner should
be via a suitable tapping made in the top of
the tank, and the fuel feed pipe should
extend to not less than 100mm above the
bottom of the tank. A non return valve with a
metal to metal seat should be fitted,
especially if the return pipe work is
terminated at a level above the draw off tube.
The non- return valve must be removable for
service and maintenance purposes, and the
return pipe from the pump must therefore be
extended down into the tank to the same
level as the suction pipe. The use of a Fuel
Deaerator in this type of installation will
reduce the need of a return pipe back to the
tank
Caution
The Deareator must be fitted the burner
side of the inlet fuel filter
Maximum lift should not exceed 3.5 metres,
and the vacuum should not exceed 0.4 bar.
Each heater must have a separate fuel
supply.
Note
It is strongly recommended that the separate
manual concerning the operational details of
the burner supplied with the heater as part of
the information package is studied prior to
installation
Gravity feed system
For installations where the oil tank is 200mm
or more above the level of the fuel pump the
principle of gravity feed may be used.
The draw off point for the supply to the
burner must not be positioned any lower than
100mm above the bottom of the tank.
Where a return valve is fitted this must be
tamper proof to prevent inadvertent
operation.
Each heater must have a separate fuel
supply
Pressurised ring main system
This system is used to supply a number of
units from a common storage tank.
A booster pump is used to provide the
pressure to push the oil around the ring main
and back to the tank. Pressure reducing
valves should be fitted on the delivery pipe to
each heater to ensure that the delivery
pressure at the heater is less than
6 psi .