HAMWORTHY HEATING LTD
WARMWELL
500001091/F
Gas Pressure Switch Location
Key:
I
- Gas Pressure Switch
II
- Main Gas Valve
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
11.5 BOILER CHECKS PRIOR TO LIGHTING
IMPORTANT!
Check that link LK9 has been removed from the
main PCB. Refer to Figure 11.1 (p26) and
Section
11.4
(p24).
Ensure that the gas supply is connected but turned
to the ‘OFF’ position. Remove the cover on the low
gas pressure switch and connect a multi-meter
across terminals ‘C & NO’ - to measure circuit
continuity.
Connect a manometer suitable for 50mbar to the
pressure tapping on the switch body and gradually
turn ‘ON’ the gas supply. The switch should operate
at approximately 20mbar - noted on the multi-meter.
Turn ‘OFF’ the gas supply and undo the pressure
test point on the gas valve inlet and allow the gas
pressure to fall. The switch should operate at
approximately 20mbar - noted on the multi-meter.
11.5.1 Gas Pressure Adjustment
After approximately 30 minutes of normal firing,
connecting a manometer to test point on the
manifold should check the manifold gas pressure.
Minor adjustments to the appliance governor may
be necessary to correct for site gas pressure
conditions.
NOTE:
The above is a first order check. Final
setting must be made using a gas meter.
11.5.2 Combustion Checks
A flue gas sampling point is provided in the front
boiler casing (see Figure 11.0 p25). 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.
I
II
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Summary of Contents for Warmwell 120
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