Opel Frontera UBS. Manual - part 894

When the engine warming up, the warmed engine
coolant is sent out into the heater core. The heater
system supplies warm air into the passenger
compartment to warm it up.
Outside air is circulated through the heater core of
the heater unit and then back into the passenger
compartment. By controlling the mixture of outside
air and heater core air, the most comfortable
passenger compartment temperature can be
selected and maintained.
The temperature of warm air sent to the passenger
compartment is controlled by the temperature
control knob. This knob acts to open and close the
air mix door, thus controlling the amount of air
passed through the heater core.

The air select knob, with its different modes, also
allows you to select and maintain the most
comfortable passenger compartment temperature.
The air source select lever is used to select either
“FRESH” for the introduction of the outside air, or
“CIRC” for the circulation of the inside air. When
the lever is set to “FRESH”, the outside air is always
taken into the passenger compartment. When
setting the lever to “CIRC” position, the circulation
of air is restricted only to the inside air with no
introduction of the outside air and the air in the
passenger compartment gets warm quickened.
However, the lever is normally set to “FRESH” to
prevent the windshield from clouding.

1A – 2 HEATING AND VENTILATION

GENERAL DESCRIPTION

HEATER

Side def hose

Vent box

Upper center vent duct

Lower center
vent duct

Blower assembly

Control lever assembly

Evaporator
assembly

W/A/C

W/O A/C

Duct

Heater unit

Lap vent nozzle

Vent box

Side def hose

Defroster nozzle

Rear heater duct

A/C - Air Conditioning

This illustration is based on LHD

This illustration is based on LHD

Temperature control knob

A/C switch (W/A/C)

TEMP

A / C

Fan control knob(Fan switch)

Air source select lever

Air select knob

HEATING AND VENTILATION  1A – 3

The vehicle has cable-control-type to control by
cable the mode and temperature of the heater unit
and the mode door for the air source of the blower
assembly.

The fan control is used to control the amount of air
sent out by the resistor at four levels from “LOW”
to “HIGH”.

CONTROL LEVER ASSEMBLY

VENTILATION

Set “AIR SOURCE SELECT LEVER” to “FRESH”
position and turn on the blower fan. Heating can be
done in this lever position, sending in fresh air from
outside.

The blower fan also serves to deliver fresh outside
air to the vehicle interior to assure adequate
ventilation.

1A – 4 HEATING AND VENTILATION

AIR SELECT KNOB

The air selector knob allows you to direct heated air
into the passenger compartment through different
outlets.
1.

Vent - In this position, air is discharged from
the upper air outlet. Air quantity is controlled
by the fan control knob.

2.

Bi-Level - In this position, air flow is divided
between the upper air outlets and the foot air
outlets, with warmer air delivered to the floor
outlets than the air delivered to the upper air
outlets.

3.

Foot - In this position, air flow is delivered to
the foot while sending approx. 30% of total
amount of air to the windshield

4.

Def/Foot - In this position, air flow is delivered
to the foot, while sending approx. 40% of total
amount of air to the windshield.

5.

Defrost - In this position, most of the air is
delivered to the windshield and a small
amount is delivered to the side windows.

Moving the air source select lever to the “CIRC”
position provides quickest heat delivery by closing
the blower assembly mode door. In this position,
outside air is not delivered to the passenger
compartment.

AIR SOURCE SELECT LEVER

The intake of outside air and the circulation of inside
air are controlled by sliding this lever left or right.

FAN CONTROL KNOB

This knob controls the blower motor speed to
regulate the amount of air delivered to the defrost,
foot, and ventilation ducts:
1.

Low

2.

Medium Low

3.

Medium High

4.

High

TEMPERATURE CONTROL KNOB

When the temperature control knob is in the
“COLD” position, the air mix door closes to block
the flow of air to the heater core.

When the temperature control knob is in the

“HOT” position, the air mix door opens to allow air
to pass through the heater core and heat the
passenger compartment.
Placing the knob in an intermediate position will
cause a lesser or greater amount of air to reach the
heater core. In this mode the passenger compart-
ment temperature can be regulated.

Heater core

Heater unit

TO VENT OUTLET

Air mix door

VENT MODE

TO FOOT

TO VENT OUTLET

BI-LEVEL MODE

FOOT MODE

TO FOOT OUTLET

TO DEF OUTLET(LHD)

DEF/FOOT MODE

TO FOOT OUTLET

TO DEF OUTLET

DEF MODE

TO DEF OUTLET

:  COLD AIR

:  HOT AIR

:  TEMP.CONTROLLED AIR

Full hot switch

Ceramic heater

Heater unit

HEATING AND VENTILATION  1A – 5

CERAMIC HEATER

When the fan control knob (fan switch) turns on with the temperature control knob set to “FULL HOT” (full
hot switch “ON”), the ceramic heater in the heater unit gets hot, thus causing the heater blow temperature
of diesel vehicle to get high to improve the heating performance (Since the engine coolant temperature of
diesel vehicle is low, its blow temperature is also low.).

Glow plug

Full hot switch

Fan switch

Thermo switch

Less than 80°C (177.8°F)

CERAMIC HEATER

“ON”

CERAMIC HEATER

“OFF”

OFF

ON

OFF

OFF

OFF

ON

ON

ON

This illustration is based on RHD