andrews L24/31, Installation Manual, Operation And Service Manual

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SERVICING SECTION 6
GAS CONTROL
VALVE
STANDARD
RANGE
GAS CONTROL
VALVE
HI-FLO RANGE
BURNER
ASSEMBLY
HI-FLO RANGE
35
The burner assembly should be checked and cleaned annually.
NOTE! Models L62/309 and L54/399 are fitted with an anchor bracket between the
burner manifold and heater body. Take out 2 screws to remove.
1. Turn gas control valve knob to OFF and disconnect union joint from gas service cock.
2. Disconnect thermostat connections (black, red and white wires) from gas control valve.
3. Remove two screws and slide out burner assembly.
4. Disconnect pilot tube and thermopile connections from gas valve. Remove two screws
and withdraw pilot/thermopile assembly.
5. Unscrew two wing nuts and remove draught shield. Remove four screws and
disconnect manifold from burner tray.
6. Clean burners by brushing internally and externally and by blowing through with
compressed air. Do not remove individual burners from the burner tray.
7. Remove the burner and pilot injectors and clean with acetone. CLEAN ORIFICES
WITH WOOD SPLINTER. DO NOT USE SHARP METALLIC OBJECTS.
8. Re-assemble in reverse order but note:
i) The flueways and combustion chamber must be cleaned first.
ii) Use an approved jointing compound when re-fitting burner injectors.
9. Light heater in accordance with lighting instructions. All gas joints must be checked
using leak detection fluid. Turn off and seal any leakages. DO NOT EXAMINE WITH A
NAKED FLAME.
10. Re-light the heater and set the thermostat to the user's requirements.
The gas control valve should be checked and service by a qualified person, fully
conversant with this item.
The gas control valve should be cleaned and checked.
Remove any debris from the valve inlet filter using a soft brush or by blowing
with low pressure air.
After servicing, check:-
1. Soundness of any gas joints broken or disturbed and seal any leaks.
2. Burner pressure/gas rate at maximum thermostat setting.
3. Operation of heater is correct. Reset controls to user's requirements.
Fig 27.