Vaillant Evaporator 14 kW 0020031973

The evaporator is the heat-absorbing coil in the refrigerant circuit of a Vaillant heating appliance, rated at 14 kW. It is manufactured by Vaillant under part number 0020031973 and is listed for the VWS 141/2. Its role is to take up heat from the surrounding medium so that it can be raised to a usable temperature elsewhere in the circuit.

• Heating output falls away and the appliance no longer reaches its usual flow temperature.
• Frost or ice builds up across the evaporator coil and does not clear during a defrost cycle.
• Refrigerant pressure faults or low-pressure lockouts appear on the appliance controls.
• Visible corrosion, mechanical damage or oil staining on the coil or its connections.
• Unusual noise or vibration from the unit while the refrigerant circuit is running.

• Confirm the appliance model and serial number against the manufacturer's parts list.
• Check that the part number on the existing component matches 0020031973.
• Verify the 14 kW rating is correct for your appliance variant.
• Work on the refrigerant circuit requires the appropriate F-gas competence and equipment.