HAMWORTHY HEATING LTD. PUREWELL AUTOMATIC IGNITION 500001035/G
33
11.5.2 Combustion Checks
A flue gas sampling point is provided in the front boiler
casing (see Figure No. 7). To check combustion take
a flue gas sample from each module test point and
for reference CO
2
measurements should be between
8.0% and 11.5% or 9.0 to 4.0% O
2
(dependant upon
model). Normal CO levels should not exceed 200ppm.
NOTE:
All the above measurements refer to
dry flue
gas
samples.
Gas Pressure Switch Location
Key: I - Gas Pressure Switch
II - Main Gas Valves
Gas Pressure Switch - Wiring Schematic
Gas Pressure Switch Adjustment
With the cover removed, turn the M3 nut clockwise to
increase the set point and vice-versa. Seal the
adjuster after setting.
15.0 RECOMMENDED SPARES
MECHANICAL ITEMS
PART No.
Low Gas Pressure Switch................... 339009477