Installation
surance or local codes require, go to a "lockout”
mode. Lockout will require manual reset of the
flame safeguard.
4. After completing this test, turn off the boiler and
reconnect the wire to the main gas valve. Replace
the control panel faceplate.
4
.4.2 Test of Low Water Cutoff
The boiler is furnished with a flow-switch-type low
water cutoff in the outlet nozzle.
1. Make sure the boiler is off.
2. Turn the system pump off, stopping water flow in
the system. Do not shut the pump off while the
boiler is operating.
3. Turn the boiler back on. It should
not
operate,
and a red indicator for "Low Water" or "Water
Flow" should be illuminated.
Perform appropriate tests on any external probe-type
low water cutoff.
4
.4.3 Test of High-Limit Control
The boiler is furnished with a high-limit cut off.
1. With the main burner operating, turn down the
temperature setting on the "high-limit" thermostat
until the main burner shuts off. The high-limit
switch must be reset manually after testing.
This check should also be made for the "Operating
Temperature" control. (The green "Heat" indica-
tor will go out.) (See the “Installation and
Owner’s Manual,” page 8 for Lo-Hi-Lo units.)
2. Readjust thermostats to desired operating t
perature and set high-limit temperature, typic
20
°
F above operating temperature.
em-
ally
4.4.4 Test of Gas Pressure Switch
Reset
Figure 4-6 Gas Pressure Switch
The boiler is furnished with a low gas pressure switch.
1. Slowly close the manual shutoff valve (on the
natural gas supply) while the burner is operating.
The low gas pressure switch should shut down the
main burner before combustion problems are en-
countered. When the gas pressure switch opens,
the "Low Gas" or "Gas Press" indicator will illu-
minate.
2. Reopen the manual shutoff valve. The "Low Gas"
or "Gas Press" indicator should remain on until
the low gas pressure switch is reset.
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Summary of Contents for TBIG-03
Page 20: ...Gemini Twin Fuel Gas Fired Boiler 8 1 1 Wiring Diagram Lo Hi Lo 18...
Page 21: ...Parts and Technical Support 8 1 2 Control Logic Diagram Lo Hi Lo 19...
Page 22: ...Gemini Twin Fuel Gas Fired Boiler 8 1 3 Wiring Diagram On Off 20...
Page 23: ...Parts and Technical Support 8 1 4 Control Logic Diagram On Off 21...
Page 24: ......