Check The Gas Inlet Pressure; Checking Flue Integrity; Fan Pressure Test - Bosch Condens 5000W Installation And Maintenance Instructions Manual

6.2

Check the gas inlet pressure

NOTICE:
▶ Ensure that the gas inlet pressure is satisfactory with all other gas
appliances working.
▶ Do not continue with the other checks if the correct gas inlet pressure
can not be achieved.
Check the gas supply working pressures in the system conform to the
readings shown in the following table:
Natural Gas Pressure
at the meter/regulator
1.13kPa
LPG Pressure
at the meter/regulator
2.75kPa
Table 17 Gas supply working pressures
6.3

Checking flue integrity

The integrity of the flue system and performance of the boiler can be
checked via the flue.
▶ With the boiler case on and the boiler running at maximum.
▶ Insert the analyser probe into the air intake.
▶ Allow the readings to stabilise and check that:
– O is equal to, or greater than 20.6%
2
– CO is less than 0.2%
2
▶ If the readings are outside these limits then this indicates that there
is a problem with the flue system or combustion circuit.
2
1
Fig. 65 Flue integrity test
[1] Air intake sample point
[2] Flue gas sample point
Bosch Condens 5000W – 6 720 646 195 (2018/10)
at the gas control valve
1.1kPa minimum
at the gas control valve
2.75kPa
6720646195-11.1Wo
6.4

Fan pressure test

This test is to determine if the heat cell requires cleaning/attention.
Setting the boiler to maximum
1. Press and hold service button for more than 10 seconds.
2. Set the CH temperature to maximum.
– The service button will illuminate continually and the blue power
indicator will pulse 5 times.
– The boiler will stay in this mode for 15 minutes unless the service
button is pressed again.
1.
2.
Fig. 66 Set the boiler to maximum
Fan pressure measurement
▶ Remove the cover and connect a digital manometer to the fan
pressure test point.
Fig. 67 Fan pressure test point
Servicing and spares
37