Inspection And Maintenance; Draining The Boiler - Bosch Singular 4000 Installation Instructions Manual

Installation Instructions

16 Inspection and Maintenance

Annual service and maintenance is required for the safe and long service life of the
appliance, for effi cient and economical operation, and to keep the environmental
impact as low as possible. Owners/operators are encouraged to sign a service and
maintenance contract with a trained and certifi ed installer for annual servicing and
maintenance of the boiler.
WARNING: ELECTRIC SHOCK HAZARD
 Always disconnect the appliance from the main power
supply before performing any work. Disconnect the
emergency shutoff switch or disengage the heating system
circuit breaker. Take measures to prevent accidental
re-connection.
WARNING: SCALD HAZARD WARNING: SCALD HAZARD WARNING: SCALD HAZARD
 The boiler may remain hot for few minutes after it is turned  The boiler may remain hot for few minutes after it is turned  The boiler may remain hot for few minutes after it is turned
off. Wait until the boiler has cooled down before cleaning to off. Wait until the boiler has cooled down before cleaning to off. Wait until the boiler has cooled down before cleaning to
prevent burns. prevent burns. prevent burns.
WARNING: EXPLOSION!
 Close the gas supply shutoff valve prior to working on the
gas train.
 Check for gas leaks after carrying out work on the gas train.
WARNING: RISK OF FLUE GAS POISONING
 Check for leaks after carrying out work on the venting
system.
NOTICE: INSUFFICIENT ANTIFREEZE CAN ACCELERATE CORROSION
 Frost protection level has to be checked annually during the
regular scheduled maintenance of the condensing boiler.
6 0 |

16.1 Draining the Boiler

To perform maintenance tasks or to prevent the boiler from freezing when it will not
be used for an extended period, the boiler must be drained.
To drain the boiler:
1. Press the button to turn off the boiler.
2. Disconnect the power supply to the boiler.
3. Turn of the gas valve.
Gas
Figure 93
4. Turn off the water supply valve on the inlet to the boiler.
Figure 94
Singular Combi Boiler - BTC 439003301 B (2021/07)
Cold water Hot water