Bosch Singular 4000 User Manual page 13

5. Remove the boiler front cover by loosening the 2 Phillips screws securing it
to the case.
Figure 24
6. Open the drain valve.
Figure 25
7. Remove the strainer from the bottom of the boiler.
Singular Combi Boiler - BTC 439003302 A (2021/03)
Figure 26
8. Close the drain valve when the water is completely drained.
9. Remove the cold water inlet fi lter.
10. Allow the residual water to drain from the boiler.
11. When the water is completely drained, reinsert the cold water inlet fi lter and
close the drain valve.
F ollow the steps in reverse order to refl l the boiler. Be careful not to lose
the drain plug.
User Manual
| 13