3.4
INJECTORS
To access, remove burners as detailed in Section 3.3.1. Undo injectors using a spanner. Soak in a
suitable solvent to remove debris and wipe with a soft rag.
DO NOT USE metal implements to clear an injector orifice. Check seals are clean before refitting
and that this is carried out in the correct order. Refer to Section 1.6.
After replacement, check burner performance is in accordance with Sections 1.8 and 2.3.2.
3.5
THERMOCOUPLE
To remove, proceed as follows -
a) Remove control panels as detailed in Section 3.2.
b) Undo tubing nuts at pilot assembly and gas control.
c) Manoeuvre thermocouple clear.
d) Replace in reverse order.
When replacing a thermocouple, coil excess in a similar manner to original and take care not to
bend capillary sleeving to less than 12mm radius.
Take care not to overtighten valve connection.
3.6
GAS TAP
To access, remove control panel assembly as detailed in Section 3.2.
To remove a gas control, proceed as follows:-
a) Undo nut that secures burner feed pipe to control.
b) Undo pilot tubing nut.
c) Remove fixings that secure control to float rail.
d) Manoeuvre control to enable thermocouple removal.
e) Withdraw control.
When replacing a control, ensure sealing gasket is in a serviceable condition and check gas
tightness.
Set/check LOW FLAME as detailed in m) - q) below. To clean and lubricate a tap, proceed as follows:-
Plugs and bodies are machined in pairs and parts are not interchangeable. Always clean one tap at
a time.
f)
Remove fixings which retain front securing plate whilst holding plate against internal spring pressure.
g) Carefully withdraw plate with operating spindle.
h) Withdraw exposed rod, spring, brass washer and sealing washer. Take care not to lose any of
these small parts.
k) Withdraw plug and clean with a soft rag at the same time as control body mating. Ensure grease
does not block plug hole or tap body holes - this will affect gas flow. Regrease plug sparingly with
an approved heat resistant grease. Re-assemble strictly in reverse order and take care with central
pin assembly. i.e. fit pin spring first followed by brass washer and sealing washer. When
inserting into plug, ensure sealing washer locates snugly in recess at plug hole bottom.
When re-assembling operating spindle, the niting pin should engage within plug slot. When
replacing control, ensure sealing gasket is in serviceable condition and check gas tightness. Take
care not to bend thermocouple capillary to less than 12mm radius.
m) LOW FLAME setting can be adjusted by means of a screw on control front
(refer to Figure 2)
. If
necessary, adjust flame by following procedure:-
n) Turn adjusting screw fully anti-clockwise.
p) Light burner and turn to LOW setting.
q) Observe flame and if necessary turn screw very slightly to obtain a satisfactory condition. Turn
anticlockwise to increase flame and vice-versa. Aim to achieve 80% of maximum flame. On
multiple burner units, all burners must be adjusted in a similar fashion. Check basic flame
stability and that cross-lighting at low flow is satisfactory.
