Weil-McLain LGB-5 - Manual (Page 5)

LGB LGB LGB LGB LGB-4 -4 -4 -4 -4 & 5 5 5 5 5 • Control Supplement • UCS • Propane
5 Part Number 550-141-919/0304
All wiring must be installed according to requirements
of the National Electrical Code and any national, state
or local code requirements having jurisdiction. All
wiring external to boiler jacket must be N.E.C. Class 1.
The boiler must be electrically grounded according to
the National Electrical Code, ANSI/NFPA No. 70 latest
edition. Use 105
o C thermoplastic wire, or equivalent, if
any original wire must be replaced. GND (burner)
lead wires must be 125
o C wire.
Canadian installations must conform to CSA C22.1
Canadian Electrical Code Part 1 and any local or
provincial codes.
Wiring to boiler must be No. 14 gauge or heavier.
Install in conduit.
A separate electrical circuit with a fused disconnect
switch (15 amp. recommended) should be used for the
boiler.
• Determine right or left electrical supply wiring.
• Attach electrical junction box to inside jacket end
panel. Screws and nuts are provided.
• Attach control transformer to junction box.
• Complete wiring per wiring diagram, Figure 2,
pages 4 and 5.
• Install ignition control ground connection as
shown in Figure 1 and wiring diagram, Figure 2.
• In Canada — attach chain between junction box
and transformer with S-hooks.
Wiring
procedure
Wiring
requirements
a. Pilot gas valve opens (provided Pilot Switch
Box is satisfied of flame on standing pilot).
b. Pilot ignition spark begins.
c. Pilot ignites.
d. Pilot proves.
e. Main gas valve opens.
f.
Main burners ignite.
3. Boiler shuts down when operating control satisfied.
Figure 2 Wiring diagram
For your safety, turn off power supply before making
electrical connections to avoid possible electrical shock
hazard.
Label all wires prior to disconnection when servicing
controls. Wiring errors can cause improper and
dangerous operation resulting in servere personal
injury, death or substantial property damage.
On failure to sense pilot flame, Ignition Control will
wait 5 minutes then retry for ignition. On failure of the
thermocouple to sense flame at the standing pilot, the
Pilot Switch Box will open the circuit, preventing
operation of the boiler and requiring the pilot to be
manually ignited before restarting.
"Hot" side of line voltage to boiler must be wired
directly to limit circuit, then fed to transformer
primary.
Sequence of
operation
1. Operating control begins start-up sequence.
a. Limit control contacts are closed.
2. Ignition control module energized.