Bosch Greenstar 12i Service Manual download pdf (Page 43)

SERVICE AND SPARES

6 720 644 743b (2011/08)

6.2 CHECK THE GAS INLET PRESSURE

Refer to section 5.5.1 for more information

B Check the gas supply working pressures in the system

conform to the readings shown in the table below:

Fig. 69 Natural gas pressures

Fig. 70 L.P.G. pressures

6.3 CHECKING FLUE INTEGRITY

The integrity of the flue system and performance of the

boiler can be checked via the flue turret sample points.

Fig. 71 Flue test points

B With the boiler case on and the boiler running at

maximum.

B Insert the analyser probe into the air intake test point.

B Allow the readings to stabilise and check that:

– O

is equal to, or greater than 20.6%

– CO

is less than 0.2%

B If the readings are outside these limits then this

indicates that there is a problem with the flue system

or combustion circuit.

Fig. 72 Flue integrity test

NOTICE:

B Ensure that the gas inlet pressure is

satisfactory with all other gas appliances

working.

B Do not continue with the other checks if

the correct gas inlet pressure can not be

achieved.

Natural gas

Allowed mbar pressure drop

meter/

regulator

across

pipework

boiler

inlet

across

boiler

gas control

valve

19 - 23 1 18-22 1.5 16.5 - 20.5

L.P.G.

32 - 45 2.5 29.5 - 42.5 1.5 28 - 41

mbar range

≤ Equal to or less than .....

Meter

Boiler inlet

Gas Control

valve

19 - 23 mbar

18 - 22 mbar

16.5 - 20.5 mbar

1 mbar

drop

1.5 mbar

drop

Natural Gas

< 2.5mbar

difference

6720644744-44.2Wo

Gas Control

valve

L.P.G.

< 4.0mbar

difference

Regulator

Boiler inlet

32 - 45 mbar

9.5

- 42

28 - 41 mbar

2.5 mbar

drop

1.5 mbar

drop

6720644744-45.2Wo

Flue gas sample point 1

Air inlet sample point 2

Tab. 26 Key to figure 71

6720643895-67.1Wo

6720643895-104.1Wo

1 2 ... 38 39 40 41 42 43 44 45 46 47 48 ... 71 72

Comments to this Manuals

No comments

Bosch Greenstar 12i Service Manual Page 43

Comments to this Manuals

Related products and manuals for Water heaters & boilers Bosch Greenstar 12i