Patterson-Kelley TBIG-03 - Manual (Page 10)

Gemini™ Twin-Fuel Gas-Fired Boiler
service power
shutoff switch
Figure 4-4 Service Power Shutoff Switch
(located inside the auxiliary panel at the back of the boiler)
General Warning
Warning! After checking controls by manual readjust-
ment, make sure they are always returned to their
proper settings.
NEVER attempt to operate a boiler that has failed to
pass all the safety checks outlined below.
4.4.1 Test of Ignition Safety System
high limit
reset
high limit/operating
temperature
adjustments
lo-hi-lo
controller "on"/"off"
switch
fuel
selector
switch
flame control
reset switch
propane
in-use
indicator
Figure 4-5 Lo-Hi-Lo Control Panel (faceplate opened)
high limit
reset
high limit temperature
adjustment
"on"/"off"
switch flame control
reset switch
operating temperature
adjustment
propane in-use
indicator and
fuel selector switch
(on side)
Figure 4-5a On-Off Control Panel (faceplate opened)
The boiler is provided with an ignition safety system.
1. Open the faceplate on the control panel. Discon-
nect wire # 17 (Lo-Hi-Lo) or # 26 (On-Off) at the
terminal block on the control panel. Disconnect-
ing this wire disables the main gas valve, ensuring
that gas cannot flow during the test.
2. Turn on the circulating water pump. With the
natural gas shutoff and secondary shutoff open
and the pilot gas cock open, turn the operating
temperature control until the boiler cycles “on.”
3. Observe the operation of the boiler. After all the
safety limits on gas pressure, water flow, and tem-
perature are satisfied, the blower will run and pre-
purge the boiler. When air flow is established, the
ignition transformer and pilot will operate. Both
functions will be indicated by separate green
lights on the control panel. If a satisfactory pilot
is established, the green "Ignite" light will extin-
guish and the pilot will remain on, alone, for 10
seconds. After 10 seconds, the green "Main Gas"
light will go on. (The main gas valve will not
open with the wire disconnected and gas cannot
flow to the burner). The "Pilot" will remain on,
along with the "Main Gas," for another 10 seconds
and then go out. Since the main flame cannot be
burning, at this point there will be no flame signal
and the flame safeguard programmer will assume
a "Flame Failure" and will either re-cycle through
the complete pre-purge and ignition cycle or, if in-
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