INSTALLATION AND OPERATION INSTRUCTIONS
4-6
SL 20-115 MODULATING GAS BOILER
4.2.1 Fan and gas valve removal instructions
1.
turn off electric power and gas supply to the boiler.
2.
ensure boiler cools down to ambient temperature. do not drain the boiler
unless freezing conditions are expected during this procedure.
3.
remove front cover, then remove boiler upper-front cover by removing the
two yellow thumbscrews at the top right and left corner of the boiler. no tools
are required.
4.
a ladder or step may be required to have a clear vertical view of the work
area. do not attempt to reach from the front without a clear view, as damage
to connectors, screws or refractory may occur.
5.
unplug both electrical connectors from the fan.
6.
unplug the electrical connector from the gas valve by removing the 1/4”
connector attaching screw.
7.
Position the harnesses out of the way of the heat exchanger lid.
8.
unplug the clear tube from the swirl plate pressure reference port.
9.
Disconnect (flare-fitting) nut on gas supply line.
10.
remove the 2 hex socket screws plus 2 hex nut screws that attach the fan to
the fan coupler.
11.
With the gas valve and swirl plate still attached, remove the fan by
pulling straight out ensuring that no wires are caught. Place the removed
components in a clean, dry area.
12.
if the fan is being replaced: With a permanent marker or equivalent, make
an alignment mark between the fan and swirl plate adapter and remove the
screws that attach the gas valve/swirl plate assembly to the fan.
4.2.2 Fan and gas valve re-installation
1.
if the gas valve has been removed, reattach it to the swirl plate.
2.
re-attach gas valve and swirl plate assembly onto fan observing the
alignment marks made during disassembly.
3.
ensure that fan (orange) gasket is in place.
4.
re-install fan-gas valve assembly onto fan coupler, tightening the 2 hex
socket screws and 2 hex nut screws by hand then an extra 1/2-1 turn.
5.
re-plug both upper and lower fan harness connectors.
6.
re-plug gas valve connector and tighten up retaining screw.
7.
if a new gas valve is being installed, remove the protective cover from the
gas inlet now.
8.
Re-attach the gas supply line JIC connector (flare-fitting nut).
9.
re-connect clear pressure reference tube onto swirl plate port.
10.
open up gas valve and check for possible leaks.
11.
return electric power to the boiler and perform start up routine.
12.
Check for gas or fumes leaks after 10 minutes of continuous operation.
Fan mounting screws
Fan/Burner Gasket
Gas valve connection block
Fan motor electrical connectors
Gas valve electrical connector
Fan pressure sensing tube