Iveco Daily Euro 4. Manual — part 220

2

CAB AIR-CONDITIONING

D

AILY

E

URO

4

”M. MARELLI” TYPE HEATER/AIR-CONDITIONER

UNIT

9

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

- Components

9

. . . . . . . . . . . . . . . . . . . . . . . . . .

HEATER UNIT

10

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

- Components

10

. . . . . . . . . . . . . . . . . . . . . . . . . .

PROCEDURE FOR EMPTYING AND REFILLING THE

AIR-CONDITIONING SYSTEMS WITH
R134A REFRIGERANT

11

. . . . . . . . . . . . . . . . . .

- R134A refrigerant recovery and refilling

station (99305146)

11

. . . . . . . . . . . . . . . . . . . . .

CONTROL FASCIA

12

. . . . . . . . . . . . . . . . . . . . . . . .

SAFETY STANDARDS

14

. . . . . . . . . . . . . . . . . . . . . .

OPERATION FLOW CHART

15

. . . . . . . . . . . . . . . .

RECOVERING REFRIGERANT

FROM THE VEHICLE SYSTEM

16

. . . . . . . . . . .

CREATING A VACUUM IN THE SYSTEM

18

. . . . . .

RESTORING OIL IN THE SYSTEM

20

. . . . . . . . . . . .

FILLING THE SYSTEM WITH REFRIGERANT

21

. . . .

CHECKING THE PRESSURES IN THE SYSTEM

23

. .

OPERATIONS PRIOR TO DISCONNECTING

THE STATION FROM THE SYSTEM

23

. . . . . .

LEAK FINDER FOR AIR-CONDITIONING

SYSTEMS WITH HFC R134A (9905147)

23

. . . .

CAB AIR-CONDITIONING

General

The purpose of the air-conditioning system is to make the cab comfortable as regards the following parameters:

- temperature and relative humidity of outside air;

- temperature and relative humidity in the cab.

The system subjects the air to thermodynamic transformations that affect its temperature, relative humidity and purity. This is
accomplished by:
- Ventilation, or introducing air taken from the outside (therefore with the temperature and humidity of the surrounding

environment) into the cab.

- Air-conditioning, or cooling and de-humidifying the air, with the possibility of heating it afterwards as preferred so as to

change the temperature and humidity in the cab.

VENTILATION

Description

Ventilation is the function of drawing in fresh air from the outside, cleaned of pollen and dust by a special filter, or recycling the
air in the cab.

This system is composed of a shell, designed to house the electric fan unit, air ducts, fresh air intake and recycled air intake. The
electric fan has several speeds to draw in and circulate large masses of air.

!

Before doing any work, you MUST observe the SAFETY rules given in section 10 “Steering system”

SAFETY STANDARDS TO OBSERVE WHEN WORKING ON VEHICLES EQUIPPED WITH
THE AIR-BAG SYSTEM

CAB AIR-CONDITIONING

3

D

AILY

E

URO

52279

Figure 1

AIR-CONDITIONING AND HEATING

Description

This is accomplished by integrating an air-conditioning and a
heating system.

This integration makes it possible to change the temperature
and humidity in the cab.

Air-conditioning

Air-conditioning is accomplished by taking advantage of the
high capacity of some gases to lower temperature
considerably in their phase of expansion, thereby making it
possible to absorb heat from the cab.

This condition is obtained by two different levels of pressure
(high, when the refrigerant fluid is in its liquid state, and low,
when the fluid is in its gaseous state) that are established and
maintained during operation of the system.

A. Refrigerant liquid inlet - B. Refrigerant liquid outlet - H. High-pressure circuit - L. Low-pressure circuit.

1. Condenser - 2. Three-level pressure switch - 3. Drier filter - 4. Compressors - 5. Heater/fan unit - 6. Evaporator -

7. Expansion valve - 8. Pollen filter.

Heating

Heating is accomplished by a radiator, in the heater unit, in
which the engine coolant circulates.

Special doors allow air to pass through the radiator only
when the heating function is activated.

The main components of the air-conditioning and heating
system comprise:

- compressor (4);
- condenser (1);
- drier filter (2);
- three-level pressure switch (3);
- expansion valve (7);
- evaporator (6);
- heater/fan unit (5);
- pollen filter (8).

L

AIR-CONDITIONING SYSTEM MAIN COMPONENTS AND FUNCTIONAL DIAGRAM

4

CAB AIR-CONDITIONING

D

AILY

E

URO

4

52281

52282

52283

Figure 2

Figure 3

Figure 4

The compressor is located between the evaporator and the
condenser. Its function is to:
- draw refrigerant fluid in the form of vapour at low

pressure and low temperature from the evaporator
through the inlet (2);

- compress the refrigerant fluid drawn up and introduce

it at high temperature and high pressure into the
condenser through the outlet (1).

The compressor is driven by the electromagnetic friction
device mounted on the compressor shaft.

The electromagnetic friction device is composed of an
electromagnetic coil (2), a pulley (1) and a front disc (3).

When the system is not running, the pulley (1) turns idle on
the bearing (4) since it is driven by the engine via the V-belt.

On

switching

on

the

air-conditioning

system,

the

electromagnetic coil (2) attracts the front disc (3) on the
pulley (1) that comes to be virtually keyed onto the
compressor shaft and makes it rotate.

The condenser is a heat exchanger located between the
compressor and the drier filter. Its function is to transform the
refrigerant fluid from its gaseous to its liquid state.

This transformation is made by the refrigerant fluid releasing
heat to the outside air. This is why the condenser is installed
on the vehicle so as, in the best conditions, to take advantage
of the air stream produced by the forward motion of the
vehicle.

553239

Compressor

553232

Condenser

CAB AIR-CONDITIONING

5

D

AILY

E

URO

MAIN COMPONENTS

Specifications and data

COMPRESSOR

Type

SCO 8 C

Displacement

cm

3

80 cm

3

Stroke

mm

33

Rev. No.:

Max

RPM

7800

Refrigerant

Oil type

ND - OIL 8

Refrigerant amount

kg

0.72

Oil amount

80

± 20 cm

3

Airtightness test

3.14 MPa

Pressure test

High

530 MPa

Low

250 MPa

ELECTROMAGNETIC FRICTION

Torque

min

26 Nm

Voltage rating

V

12

Absorbed pressure

W

max 35

Weight

kg

1.5

Belt

4k-type

Pulley actual diameter

mm

105