Weil-McLain LGB-6 EN - Manual (Page 10)

10
LGB-6 to LGB-23 Series 2 – Control Supplement
Part Number 550-141-916/0304
V
Verification testing
Before starting boiler for the first time and at least annually (during annual inspection and
start-up), follow the procedures below to verify boiler controls are operating correctly and
that automatic gas valve properly shuts off gas flow. Failure to verify boiler operation
could result in severe personal injury, death or substantial property damage.
Replace any defective components. Do not attempt to operate boiler or leave boiler in
operation if any component is found to be defective or to operate incorrectly. Failure to
comply could result in severe personal injury, death, or substantial property damage.
Leak test automatic
gas valve
1. Close manual test firing valve.
2. Open the service valve and gas hand valve.
3. Install a hose barb into a pressure tap downstream of the first automatic gas valve.
Allow any accumulated gas in the line to vent off. Then connect a U-tube manometer.
If the valve seals properly, there should be no gas pressure present. Remove manometer
and hose barb and replace pipe plug in pressure tap.
4. Connect the manometer downstream of the second automatic gas valve. Temporarily
remove the power leads to the first automatic gas valve. Then connect 24 volt power to
the first automatic gas valve terminals to open it. If the second valve seals properly,
there should be no pressure at the manometer.
5. Remove the temporary power supply to the automatic gas valve. Reconnect its power
leads. Remove the manometer and plug any open pressure taps.
6. Follow Operating Instructions to place boiler in service.
Verify boiler control
sequence
1. Follow the Operating Instructions in this Supplement to start the boiler, but do not
open the manual test firing valve . Open all other manual gas valves as instructed.
Leave the manual test firing valve closed.
2. The automatic pilot burner should light.
3. After the pilot lights, the boiler controls should activate the automatic gas valves. Use a
voltmeter to verify voltage to automatic valves.
4. With no gas flow to the manifold, the boiler ignition controls should turn off the
automatic gas valves after main flame ignition trial. Use a voltmeter to verify voltage to
automatic valves is turned off.
Manual test firing
valve
This boiler is equipped with a manual test firing valve — the manual gas valve piped
between the gas manifold and the first automatic gas valve in the gas train. Closing the
manual test firing valve allows verification of proper boiler operation without allowing
gas flow to the manifold and allows leak testing of the automatic gas valves. Follow the
procedures below.