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VISCOSITY - TEMPERATURE CHART
AUXILIARY PUMP
(see BT 8511/6 and BT 8513/7)
In some cases (excessive horizontal distance, vertical distance or high viscosity and always when using the burners in
the dense “D” version) it is necessary to fit the unit with a “loop” feed system using an auxiliary pump, thus avoiding
direct connection of the burner pump to the tank.
In this case the auxiliary pump can be started as a function of burner start-up and stopped when the burner stops.
Carry out auxiliary pump electrical connections by connecting the coil (230 V) which controls the pump relay switch to
the “N” terminals (control box input terminal block) and “L1” terminals (downstream from the motor relay switch).
Always observe the following:
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the auxiliary pump must be installed as close as possible to the liquid to be sucked.
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the head must be adequate for the system in question.
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a flow-rate at least equal to burner pump flow-rate is recommended.
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connection piping must be sized as a function of auxiliary pump flow-rate.
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Never electrically connect the auxiliary pump directly to the burner motor relay switch.
