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Operation
2 - OPERATION
*
Set-point
– is the temperature figure which is desired inside the vehicle, adjusted by the operator (driver).
This air conditioning model offers different options of control. Identify the
controller visually and, after that, choose the compatible working instructions.
2.1 - OPERATION GENERAL INFORMATION
Spheros air conditioner controllers are usually installed on the driver’s
instruments dash. The controllers are composed of a display and a keyboard,
used to operate the equipment.
The display shows the operator the number regarding the internal temperature
of the vehicle.
It is also used to visualize the operation status and programming the
Set-Point
*
temperature.
The internal temperature is detected by a temperature sensor located at the
(see item 3.1)
Important: the air conditioner will only work when the vehicle’s engine is on.
It’s always recommended to turn the air conditioner off before turning off the
vehicle.
Note: Before turning on the air conditioner verify the conditions of the compressor
belts, located together to the vehicle’s engine (see item 3.1)
2.1.1 - TURNING THE CONDENSER ON
The condenser engines, as well as the compressor, will only be activated
when the air conditioner is working on the “Cooling Mode”.
2.1.2 - TURNING THE EVAPORATOR ON
The velocity control from the evaporator blower is automatically adjusted
according to the temperature programmed and the temperature inside the
vehicle.
When the internal temperature reaches close to set-point, the velocity of the
blower is reduced and when the internal temperature gets distant from set-point,
the velocity of the blower increases automatically.
For equipment installed in city line vehicles, where the cooling need is greater,
the ventilation works only on high velocity.
2.1.3 - TURNING THE COMPRESSOR ON
The compressor operates only on “Cooling Mode”, and will start operation 10
seconds after the condenser is turned on.
For safety reasons the controllers present a time histeresis set in 30sec. to
restart the compressor every time it is turned off.
2.1.4 - PROTECTION SYSTEM
The devices are equipped with an electrical system that monitors its work
pressures. The pressure switch** performs this monitoring.
When a failure in the equipment occurs and the work pressures suffer any
alteration, the controller receives a signal from the pressure switch and the
display will show a failure code (see failures on item 2 – Operation). For safety
reasons, the compressor will be automatically turned off.
Note: The working pressures are constantly monitored even when the air
conditioner is off.
** Pressure Switch
– safety device that protects the components from the air conditioning system
against high and low pressure.
