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The blower is designed on the basis of:
g
The thermal power to be drawn from the heat
exchangers in order to achieve the right flow rate
g
The head loss in the circuit, in order to set the
pressure.
The ventilation power is adjusted by
a device that controls the blower speed.
Two types of adjusting devices are used:
g
Passive resistive devices that are adjusted
in steps and contain two or three resistors
corresponding to three or four speeds.
The resistors are made of wire coils or
mounted on a ceramic support.
g
Power transistors for continuous
adjustment.
The type of control device is determined
by the system architecture.
23
Single inlet blower
and integrated electronics
Double inlet blower
Blower with housing
Resistive types
Electronic types
Blower control
Blower Types