Fuel Pipeline - Auxiliary Pump - baltur BT 15 N Manual De Instrucciones

FUEL PIPELINE
The following description covers the basic requirements to ensure effi cient operation. The unit is equipped with a
self-suction pump capable of sucking oil directly from the cistern also for the fi rst fi ll-up.
This statemet is only valid if the required conditions exist (refer to the table of distances and differences in levels
and the viscosity - temperature diagram).
To ensure effi cient operations, it is preferable to make suction and return pipes with welded fi ttings and to avoid
the use of threaded connections which often cause air infi ltrations and disturb pump operations and consequently
those of the burner. Where a removable fi tting is required, use the welded fl ange method with a fuel resistant
gasket inserted; this will ensure a perfect sealing. The attached tables show diagrams of the different types of
systems depending on the position of the tank with respect to the burner. The suction pipe should run up-slope
towards the burner to avoid possible formation of gas bubbles. Where more than one burner is installed in one
boiler room, it is essential that each burner has its own suction pipe.
Only return pipes can lead to a single manifold pipe with an adequate cross section leading to the cictern.
Never connect the return pipe directly to the suction pipe. It is advisable to properly insulate the suction and return Never connect the return pipe directly to the suction pipe
pipes to prevent cooling which would effect the unit's effi ciency.
Pipe diameters (to be strictly complied with) are listed in the following tables.
The maximum amount of vacuum that the pump can withstand when operating regularly and silently is 35 cm of
Hg; if this limit is exceeded, normal pump operations can no longer be guaranteed.
Maximum suction and return pressure = 1 bar.
When the viscosity of the fuel oil to be used exceeds the pumping limit, (see diagram) it is necessary to heat the
oil in order to ensure that it fl ows through the pipes.
Pre-heating in the cistern can be carried out with a steam coil or with a hot water coil.
The coil should be fi tted near to the suction pipe and must always be immersed even when the tank is at the mi-
nimum level. The extent of pre-heating should be decided after consulting the viscosity - temperature diagram.
The oil should be heated until its viscosity rate is under that defi ned for the pumping limit.
However, a slight pre-heating in the cistern is always advantageous even when using fl uid oils (3 ÷ 5° E).
If pre-heating is carried out with a steam or hot water coil, a considerable saving in electricity can be made; in
fact; the electrical resistances installed in the burner only higher the oil temperature when the thermal stage
corresponds to the difference in the arrival temperature at the pre-heater and the temperature at which the oil
becomes atomized. However, to avoid the formation of gas which would disturb pump operations, pre-heating in
the cistern of fuel oil (5° E at 50° C) should not exceed 30° C.
AUXILIARY PUMP
In some cases (excessive distance, difference in level or high viscosity), it is necessary to install a "loop-type"
supply system with an ancillary pump, which dispenses with connecting the burner pump directly to the cistern.
In this case, the ancillary pump can be put into operation when the burner is started up and cut off when it
stops.
The electrical connection of the ancillary pump is made by connecting the coil (230 V), which controls the pump's
relay, to terminals "N" (the control box's line unput terminal board) and "L1" (downstream the motor's relay).
It is important to comply strictly with the following provisions:
- The ancillary pump must be installed as near as possible to the fuel to be sucked.
- The head should suit the system in question.
- We recommend an output at least equal to that of the burner's pump.
- Connection pipes should be of a size to cope with the output of the ancillary pump.
- Always avoid connecting electrically the ancillary pump's motor directly to the burner's motor relay.
(see BT 8511/6 - BT 8513/7)
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98331 ed 2007/01