20 | Maintenance (only by qualified contractors)
Remove the front cover
▶ Loosen the 2 fixing screws from the front (Fig. 18, ).
Remove the front
▶ Remove the front.
▶ Fit the appliance so that it sits vertical.
Periodic maintenance works
▶ Check the proper operation of all the safety, regulation and
▶ If it is dirty:
– Dismantle the combustion chamber.
– Clean the chamber by applying a jet of water in the
lengthwise direction of the flaps.
NOTICE: Damage to the appliance.
Damage in the combustion chamber.
▶ Do not apply a jet that is too strong or
aimed in a direction other than that
▶ If the dirt persists, dip the sheets in hot water with
detergent and clean carefully.
▶ Regions with average/high water hardness: descale the
inside of the combustion chamber and the connection
▶ Fit the combustion chamber using new joints.
▶ Inspect the burner each year and clean it if necessary.
If it is very dirty, (grease, soot):
▶ Dismantle the burner.
6 720 819 528 (2016/02)
▶ Use a brush and clean the surface of the flutes.
▶ Blow the flutes using a jet of air.
▶ Close the water valve inlet.
▶ Loosen the cold water tube.
▶ Use a key and carefully pull the water filter.
▶ Replace the water filter.
▶ Loosen the fixing screw of the control box.
▶ Release all the connections to the control box.
▶ Open the control box.
▶ Replace the fuse.
▶ Re-tighten all the connections.
▶ Read the chapter 3 "Operating Instructions" and the
chapter 7 "Tuning".
▶ Check the gas control (burner pressure).
▶ Check tightness of the flue circuit (with the front fitted).
▶ Check that there are no gas or water leaks.
Replacement of fuses (control box)
Start-up after completion of maintenance
Therm 4000 S