Bosch Appliances 24I RSF manual Commissioning The Appliance, Summary

12. Commissioning The Appliance

12.1SUMMARY

The appliance is dispatched with the controls set to provide a maximum output for domestic hot water and central heating of

23.4kW (80,000 Btu/h). The appliance automatically modulates to satisfy lower heat loads.

Domestic Hot Water and Central Heating Systems. Check that both the mains water supply and central heating systems have been fully flushed out at installation.

Gas Service. The complete system, including the meter, must be inspected and tested for soundness and purged as indicated in BS 6891.

12.2APPLIANCE AND CENTRAL HEATING SYSTEM PREPARATION

Remove the cabinet front panel.

Check that the electrical supply and the gas service to the appliance are off.

Check that all the water connections throughout the system are tight.

Open the system valves at the appliance. Open all the radiator valves, fill the system and vent each radiator in turn.

Remove the inner casing cover as described in section 14.3(b). See Fig 24.

Fig. 24. Appliance casing and control equipment fixings.

Inner casing	Side casing
	fixing
cover
	screws (4)
screws (4)

Facia panel fixing screws (2)

Bottom facia panel fixing screws (3)

The automatic air vent will vent the appliance. Check that the air vent cap has been removed. See Fig. 25.

Check that the pressure relief valve operates by turning the knob anti-clockwise until it releases. Water should be expelled from the discharge pipe. See Fig. 26. Lower the control box to gain access. Refer to Section 14.3(c).

Set the Expansion Vessel Pressure

The charge pressure of the expansion vessel as dispatched is 0.5 bar, which is equivalent to a static head of 5 metres (17ft). The charge pressure must not be less than the static head at the point of connection. A Schraider type tyre valve is fitted to the expansion vessel to allow the charge pressure to be increased if necessary.

Set the System Pressure

Fill the system until the pressure gauge shows 2.5 bar (37 lb/ins2) and check for water soundness. Release water from the system using the relief valve test knob until the initial System Design Pressure is obtained, up to a maximum of 1.5 bar.

Initial System Design Pressure (bar) = Expansion Vessel Charge Pressure +0.3 (bar).

Fig. 25. Appliance components and fixings (upper assembly).

Flue hood	Flue Gas	Fan assembly
	Test Point
		fixing screws (4)

Overheat thermostat

Auto air vent

Combustion chamber

cover fixing clips (2)

Burner fixing screws (2)

Note: 1 bar is equivalent to 10.2 metres (33.5 ft) of water.

Set the movable pointer on the pressure gauge to coincide with the indicating pointer giving a permanent record of the set system pressure.

If the pressure indicated on the pressure gauge is greater than

2.6bar when operating at the maximum central heating temperature, an extra expansion vessel must be fitted to the system as close as possible to the appliance central heating return connection.

The appliance (as dispatched) can accommodate a system volume of about 100 litres. Refer to BS 7074 Part 1. If the system volume is in excess of that accommodated by the expansion vessel fitted to the appliance then an extra vessel must be fitted as close as possible to the central heating return connection of the appliance.

Any extra vessel fitted must be pressurised to the same figure as the integral vessel. If the expansion vessel fails then the specified replacement must be fitted.

Fig. 26. Pressure relief valve.

Pressure relief valve.

(Turn knob anti-clockwise to test).

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