Heater unit - overhaul

1 With the heater unit removed from the vehicle, remove the two securing screws and withdraw the heater matrix from the casing (see illustrations).

19.1a Remove the securing screws . . .
19.1a Remove the securing screws . . .

19.1b . . . and withdraw the heater matrix
19.1b . . . and withdraw the heater matrix

2 Cut the heater casing gasket in line with the casing joint, then use two suitable screwdrivers to prise off the retaining clips and separate the casing halves. Withdraw the lower part of the casing to the side.

3 Remove the air flap valves, then press the control levers from the casing. Note that the “up/down” control lever can only be removed when the marks are aligned as shown (see illustration).

19.3 Heater “up/down” control lever must be aligned as shown before removal
19.3 Heater “up/down” control lever must be aligned as shown before removal Note that the cross marks are for right-hand drive vehicles

4 Clean all components and hose through the matrix to remove any debris. If necessary use a chemical cleaner to clear the inner passage of the matrix. Renew the components as necessary.

5 Reassembly is a reversal of dismantling.

    See also:

    General information
    1.6 litre engine The 1.6 litre CVH engine was introduced in September 1991, to replace the 1.6 litre SOHC engine used previously in the Sierra range. The engine is broadly similar to the 1.8 litr ...

    Engine electrical systems
    General information and precautions General information The electrical system is of the 12 volt negative earth type, and consists of a 12 volt battery, alternator with integral voltage regulator, ...

    Fuel system - depressurising
    Warning: The fuel system will remain pressurised after the engine is switched off. Comply with relevant safety precautions during this operation and refer to the “Safety First” Section at the beg ...