INSTALLATION AND OPERATION INSTRUCTIONS
3-6
SL 80-399 MODULATING GAS BOILER
SL 26-260 G3, SL 40-399 G3 MODULATING GAS BOILERS
NOTE
The safety warning regarding
burner refractory on page 4-2 of
this manual must be observed.
Heat Exchanger Lid removed
Refractory removed
Burner and Heat Exchanger Lid
3.4.1 Gaining access to combustion chamber and
burner removal instructions
SL 26-260 G3
1. Remove the fan and gas valve assembly.
See “Fan and gas valve removal
instructions” on page 4-6 of this manual.
2. Disconnect the igniter cable, gas valve cable and the two fan plugs, and move them
out of the way.
3. Remove the two screws that secure the igniter to the lid using a # 2 Phillips
screwdriver.
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 8 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 or equivalent, make an alignment mark between the lid,
gasket, and heat exchanger.
8. 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.
9. 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
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.
10. Place the lid with the burner attached, on a clean dry area.
11. 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.
12. Carefully remove the refractory, and place it in a clean dry area.
13.
If the burner needs to be removed, gradually loosen the five screws that secure the
burner to the heat exchanger lid with a # 2 Phillips screwdriver. Then remove the
screws and the burner.
SL 40-399 G3
1. Remove the fan and the gas valve assembly. See “Fan and gas valve removal
instructions” on page 4-6 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 with a # 2 Phillips
screwdriver.
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. Loosen the lid fasteners located around the top edge of the heat exchanger, and
swing the bolts off the lid and let them hang down.
7. With a permanent marker or equivalent, make an alignment mark between the lid and
heat exchanger.
8. 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.
9. Carefully lift the lid-burner assembly straight up and out of the heat exchanger, being
careful not to damage the refractory.
10. Place the lid with the burner attached, on a clean dry area.
