Engine Cooling and Cabin Air Conditioning Systems — Specifications (Audi A4 B7)

Table of contents: Refrigeration unit ↓ Engine cooling system ↓ Climate system ↓

Coolant type and volume - see Specifications to Chapter 1

Test pressure of the engine cooling system, bar - 1

Excess opening pressure of the safety valve in the expansion tank cap, bar — 1.4÷1.6

Temperature of beginning of opening // full opening of thermostat,°C

Mechanical thermostat 87 // 102
Electric thermostat 105// —

Thermostat valve stroke, mm

Mechanical thermostat - not less than 8
Electric thermostat - not less than 7

Resistance of the heating element of the electric thermostat at 25°C, Ohm — 14÷16

Refrigeration unit

Refrigerant type - R135a*

Type of refrigeration oil - PAG refrigeration oil

Amount of refrigeration oil**, g

8-cylinder engines - 130 ±10
Other engines - 130 ±10

Amount of refrigerant (models A4 // RS4)**, g — 500 // 440 ±20

Pressure in refrigerant lines (bar) with ignition off depending on temperature

15°C — 3.9
20°C — 4.7
25°C — 5.6
30°C — 6.7
35°C — 7.8
40°C — 9.1
45°C — 10.5

* Mixing of R 134a and R12 refrigerants is not permitted.

* * If the data provided contradicts the data indicated on the nameplate in the engine compartment, the latter should be used as a guide.

Tightening force of threaded connections, Nm

Engine cooling system

Coolant drain plug in the engine thermostat housing

4.2 l (S4) — 25
4.2 l (RS4) — 4

Drain plug on the front coolant hose of the 4.2 L engine (RS4) - 10

Radiator shroud fasteners

Thread M5 // M6 — 4.5// 11

Panel bolts - 2

Fastening the fan to the radiator shroud