4-7
TROUBLESHOOTING
SL 26-260 G3, SL 40-399 G3 MODULATING GAS BOILERS
10. With the venturi mixing device still attached, remove the fan by pulling straight up
ensuring that no wires are caught and that the gas line remains in place. Place the
removed components in a clean, dry area.
11. Note how the venturi mixing device is positioned on the fan before removing it from
the fan. Remove the three Phillips head screws to separate the venturi mixing device
from the fan.
12. Attach the venturi mixing device to the new fan.
4.2.2 Fan and gas valve re-installation
SL 26-260 G3
1. If the gas valve was removed from the venturi, ensure the gasket is in the proper
position.
2. Attach the gas valve to the venturi mixing device with the brass coupler nut.
3. Re-install the fan and gas valve assembly onto the lid using the four 8 mm hex bolts
removed earlier.
• Ensure the black gasket is installed between the fan outlet and the lid.
• Tighten by hand plus an extra 1/8 of a turn the 4 hex bolts.
• Test for leaks around the fan and lid gasket.
4. Re-attach both fan harness connectors.
5. Re-attach the gas valve connector.
6. If a new gas valve is being installed, remove the protective cover from the gas inlet
now.
7.
Re-attach the gas supply line JIC connector (flare-fitting nut).
8. Open up the gas supply, and check for possible leaks.
9. Return the electric power to the boiler, and perform the startup routine.
10. Check for gas or fume leaks after 10 minutes of continuous operation.
SL 40-399 G3
1. If the gas valve has been removed, reattach it to the corrugated gas line.
2. Re-attach the venturi mixing device to the new fan, observing the alignment marks
made during disassembly.
3. Ensure that the fan gasket is in place (between the heat exchanger lid and the fan).
4. Re-install the fan and venturi assembly onto the heat exchanger lid, tightening the
four hex nuts by hand plus an extra 1/2 turn.
5. Plug in both the upper and lower fan harness connectors.
6. Plug in the gas valve connector.
7. If a new gas valve is being installed, remove the protective cover from the gas inlet
now.
8. Re-attach the gas inlet block onto the gas valve, ensuring that the O-ring seal is in
place. If this O-ring is lost, it must be replaced with a factory supplied O-ring.
9. Tighten by hand plus an extra 1/2 turn in cross sequence the 4 gas inlet block screws.
10. Open up the gas supply valve, and check for possible leaks.
11. Return the electric power to the boiler, and perform the startup routine.
12. Check for gas or fume leaks after 10 minutes of continuous operation.
