IBC SL 20-160 G3, Installation And Operating Instructions Manual

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3-5
STARTUP AND COMMISSIONING
SL 10-85 G3, SL 14-115 G3, SL 20-160 G3, SL 30-199 G3 MODULATING GAS BOILERS
Figure 44: Gas Valve and Pressure Reference System
3.4.1 Gaining access to the combustion chamber
1. Remove the fan and gas valve assembly. See “Fan and gas valve removal
instructions” on page 4-5 of this manual.
2. Disconnect the igniter cable, and move it out of the way.
3. Remove the two screws that secure the igniter to the lid.
4. Carefully remove the igniter by sliding it straight up.
5. Remove the igniter gasket, and place the parts on a clean dry area.
6. Remove the 6 hex nuts that attach the heat exchanger lid to the heat exchanger with
a 10 mm open-end wrench or socket.
7. With a permanent marker, make an alignment mark between the lid, gasket, and heat
exchanger.
Before removing the lid, it is important to be positioned directly above it to ensure a
straight-up extraction. Failing to do this may result in refractory damage.
8. Slowly lift the lid-burner assembly off the heat exchanger. The refractory should
remain in place in the combustion chamber shoulder. Note that there is less than
a 1/8” (3 mm) clearance between the burner walls and the refractory. Care must
be observed to ensure minimal contact between these parts to prevent refractory
cracking.
9. Place the lid with the burner attached on a clean dry area.
10. (To help later in re-assembling) With a permanent marker or equivalent, make
an alignment mark on the refractory, lining it up with the same mark made earlier
between the lid and heat exchanger.
11. Carefully remove the refractory, and place it in a clean dry area.