Note. Repairs may only be carried out in specialized service centers that have the necessary equipment for work on the refrigerant circuit and qualified personnel. An assistant is required to remove and install the heater/air conditioning module. For easy access to the expansion valve, the casing and, if necessary, the suction hose should be removed on some engines.
Disconnect the negative terminal from the battery. Cars with air conditioning - disconnect the refrigerant lines from the expansion valve.
Danger! The coolant temperature of a warm engine can exceed 100°C. The cooling system is under pressure - risk of burns! Before starting repair work, release the pressure and allow the coolant to cool.
Mark coolant hoses "1" and "4".
Note: The heat exchanger is designed for the refrigerant to flow in a specific direction, so it is important not to mix up the hoses when connecting.
Clamp the cooling system hoses. Push out clamps "2" and "3". Disconnect coolant hoses "1" and "4" from the heater heat exchanger.
Attach short hose "1" to the upper nipple. Place container "2" under the lower nipple "3". Carefully blow out the remaining coolant from the heat exchanger into container "2" using a blow gun. Close the open holes of the pipes and nipples with clean plugs. Remove the front panel and the central support of the front panel.
The heater and air conditioning module is secured to the central support with three "arrow" screws (4 Nm). Remove the central air duct to the rear deflector under the central console. Lift the rear footwell deflector under the front seat and pull it back.
Disconnect connector "3" from the supply fan control unit "J126".
Having folded back the bracket "arrow" disconnect the connector "5" from the airbag control unit "J234". Cover the carpet of the floor and the airbag control unit "J234" with a liquid-impermeable film, on which is laid highly absorbent paper.
Carefully disconnect the drain hose "2" from the heater and air conditioning module.
Remove the heater and air conditioning module "1" from the brackets on the water drain box shield. Release the cable channel "3". Disconnect the wiring harness "2" from the "arrow" fasteners. Remove the heater and air conditioning module.
Installation
Installation in reverse order.
Note: To install the heater and air conditioning module, you will need assistance from a 2nd mechanic.
Install heater module "2" onto brackets "1" and "3".
Note: During installation, the brackets remain in the vehicle.
Tighten the heater and air conditioning module/support mounting screws in the sequence "1", "2" and "3" (4 Nm).
Text taken from this website: SkodaBook.ru
When installing, ensure that the drain hose "3" is positioned correctly. The "arrow" retainer of the fitting must enter the guide "2". If a clamp was used to secure the drain hose "3", replace it with a new one.
Drain hose "3" must pass under the harness of the airbag control unit "J234" pos. "4". Fill with coolant. Fill the coolant using a stand for servicing air conditioning systems. Connect the Tester, simplify and clear the event recorder. Finally, check the operation of the heater module and air conditioning system.