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Part Number 550-141-916/1001
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Part Number 550-141-916/1001
LG B-6 t o LG B-2 3 Series 2 – Control Supplement
II
Ga s p ip in g
1. Size gas piping considering —
a. Diameter and length of gas supply piping.
b. Number of fittings.
c. Maximum gas consumption (including any possible future expansion).
d. Allowable pressure drop from gas meter outlet to boiler. For pressure drops, see
ANSI-Z223.1 – latest edition. Canadian installations must comply with B149.1 or
B149.2 Installation Code.
2. Size natural gas piping from Table 3, below. Size piping to provide proper inlet pressure to
gas valve when operating at rated input.
a. Inlet gas pressure to manual main shut-off gas valve —
minimum 7" W.C. standard (5" on special order) – maximum 13" W.C.
b. If pressure to gas valve exceeds 13" W.C., install positive dead-end lockup gas pressure
regulator upstream of hand valve.
c. To obtain approximate cubic feet per hour, divide input (BTU/HR) by 1000.
3. Remove gas supply knockout disc from jacket panel.
4. Follow good piping practices.
5. Pipe joint compound (pipe dope) must be resistant to corrosive action of liquefied
petroleum gases. Apply sparingly only to male threads of pipe joints.
6. Install drip leg at inlet of gas connection to boiler. Where local utility requires,extend drip
leg to floor.
7. Install ground joint union when required for servicing.
8. Support piping by hangers, not by boiler or its accessories.
9. Purge all air from supply piping.
10. Before operating boiler,check boiler and its gas connections for leaks.
Do not check for gas leaks with an open flame – BUBBLE TEST. Failure to
use bubble test or test for leaks can cause severe personal injury, death or
substantial property damage.
a. Close manual main shut-off valve during any pressure testing at less than 13" W.C.
b. Disconnect boiler and gas controls from gas supply piping during any pressure test
greater than 13" W.C.
11. Set gas pressure switch as follows or to local inspector’s requirements (LGB-21 through
LGB-23 only):
a. High – 14" W.C.
12. Canada only - manual main shut-off valve must be identified by installer.
Pipe
Size
1 ¼"
1 ½"
2"
2 ½"
3"
4"
*Pipe length, in feet (Natural Gas capacities, listed in MBH)
Table 3
10
20
30
40
50
75
100
150
250
380
710
1,130
2,000
4,100
Natural gas supply pipe sizing
1,050
1,600
3,050
4,800
8,500
17,500
730
590
500
440
360
305
1,100
2,100
3,300
5,900
12,000
890
760
670
545
460
870
1,400
2,500
5,100
1,650
2,700
4,700
9,700
1,450
2,300
4,100
8,300
1,270
2,000
3,600
7,400
1,020
1,650
2,900
6,000
*Include measured length of gas supply piping and allowance in feet for number and size of fittings.
4
Part Number 550-141-916/1001
UniversalControlSystem –Naturalgas
III
Wirin g
For your safety, turn off electrical power supply before making any electrical
connections to avoid possible electrical shock hazard.
1. All wiring must be installed in accordance with the requirements of the National Electrical
Code and any additional national, state or local code requirements having jurisdiction. All
wiring must be N.E.C. Class 1.
2. The boiler must be electrically grounded in accordance with the National Electrical Code,
ANSI/NFPA No. 70-latest edition. Use 105 °C. thermoplastic wire, or equivalent, if any of
the original wire must be replaced (except for pilot spark, sense and ground wires).
3. Canadian installations must conform to CSA C22.1 Canadian Electrical Code Part 1 and
any local or provincial codes.
4. Supply wiring to the boiler must be No. 14 gauge or heavier. Install in conduit.
5. A separate electrical circuit with a fused disconnect switch (15 amp. recommended) should
be used for the boiler.
Sequence of operation
1. Operating control begins start-up sequence.
a. Limit control contacts are closed.
2. Pilot-proving module energized.
On failure to sense pilot flame or main flame, control will wait 5 minutes
then retry for ignition.
a. Pilot solenoid opens.
b. Pilot ignition spark begins.
c. Pilot ignites.
d. Pilot proves.
3. Main flame-proving module energized from pilot-proving module.
a. Secondary gas valve opens.
b. Main gas valve opens to low fire position.
c. Main burners ignite at low fire.
d. Main flame sensor proves low fire carryover.
e. Main gas valve opens to high fire position.
f. Main burners increase to high fire.
4. Dual base assembly (LGB-13 through LGB-23) - operating control energizes controls for
both base assemblies at the same time. See steps 1 through 3 above.
5. Boiler shuts down when operating control is satisfied.
Part Number 550-141-916/1001
5
LG B-6 t o LG B-2 3 Series 2 – Control Supplement
III
Wirin g
– continued
SCHEMATIC WIRING DIAGRAM
STEAM
LIMIT CIRCUIT
WATER
LIMIT CIRCUIT
HIGH
LIMIT
CONTROL
OPERATING
CONTROL
LOW WATER
CUT-OFF
LOW WATER
CUT-OFF
MAIN FLAME
PROVING MODULE
PILOT PROVING
MODULE
MV
MV/PV
MV
MV/PV
(NOTE 7)
PV
PV
TEMPERATURE
GND(BURNER)
GND(BURNER)
(NOTE 8)
G
G
OPERATING/LIMIT
COMBINATION
CONTROL
24V (GND)
24V
24V (GND)
24V
THESE TERMINALS
TO BE JUMPERED
WHEN L.W.C.O. IS
NOT USED
JUNCTION
BOX
MAIN FLAME
SENSOR
(NOTE 7)
WIRE NUTS (4)
PILOT
(NOTE 9)
SENSE
SPARK
SENSE
SPARK
FROM TRANSFORMER
FROM TRANSFORMER
TO LIMIT CIRCUIT
UNIVERSAL
SPARK
IGNITION
CONTROL
SERVICE SWITCH
(BY OTHERS)
HIGH GAS
PRESSURE
SWITCH
(WHEN USED)
(NOTE 5)
TERMINAL
BLOCK
WIRE TIE CLIP
TRANSFORMER
R
1
2
R
H
PRE-WIRED PANEL
FROM
FUSED
DISCONNECT
BK
FIRING RATE CONTROL
(WHEN USED)
W
BL
120
V.A.C.
24
V.A.C.
BK
PILOT SOLENOID
VALVE
N
C
MV
PV
BL
MV
PV
BL
W
MV/PV
MV/PV
W
MAIN GAS VALVE - TWO
STAGE COMBINATION
VALVE W/REGULATOR
SECONDARY
GAS VALVE
W
BK
NO. 1 BASE WIRING
WIRE NUTS (3)
(SIZES 6 THRU 23)
EQUIPMENT
GROUND
(NOTE 10)
MAIN FLAME
PROVING MODULE
PILOT PROVING
MODULE
MV
MV/PV
MV
MV/PV
(NOTE 7)
PV
PV
GND(BURNER)
GND(BURNER)
G
G
(NOTE 8)
24V (GND)
24V
24V (GND)
24V
MAIN FLAME
SENSOR
(NOTE 7)
PILOT
(NOTE 9)
SENSE
SPARK
SENSE
SPARK
UNIVERSAL
SPARK
HIGH GAS
PRESSURE
SWITCH
(WHEN USED)
(NOTE 5)
IGNITION
CONTROL
TERMINAL
BLOCK
WIRE TIE CLIP
1
2
R
PRE-WIRED PANEL
BK
FIRING RATE CONTROL
(WHEN USED)
R
C
W
BL
BK
120
V.A.C.
24
V.A.C.
PILOT SOLENOID
VALVE
MAIN GAS VALVE - TWO
STAGE COMBINATION
VALVE W/REGULATOR
MV
PV
BL
MV
MV/PV
W
PV
BL
W
MV/PV
SECONDARY
GAS VALVE
W
TRANSFORMER
WIRE NUTS (2)
BK
NO. 2 BASE WIRING
(SIZES 13 THRU 23)
LOW VOLTAGE FIELD
HIGH VOLTAGE FIELD
LOW VOLTAGE FACTORY
HIGH VOLTAGE FACTORY
ELECTRICAL SHOCK HAZARD, CAN CAUSE SEVERE INJURY OR DEATH.
DISCONNECT POWER BEFORE INSTALLING AND/OR SERVICING.
IGNITION/SENSING CABLE
NOTES:
5. STANDARD EQUIPMENT FOR LGB-21 THRU LGB-23.
MV/PV
1. ALL WIRING MUST BE INSTALLED IN ACCORDANCE WITH:
A. U.S.A. - NATIONAL ELECTRICAL CODE AND ANY OTHER NATIONAL, STATE, OR LOCAL
CODE REQUIREMENTS.
B. CANADA - C.S.A. C22.1 CANADIAN ELECTRICAL CODE PART 1 AND ANY OTHER
NATIONAL, PROVINCIAL, OR LOCAL CODE REQUIREMENTS.
MAIN GAS VALVE TERMINAL.
CONTROL MODULE TERMINAL.
6.
TERMINAL ON MAIN GAS VALVE IS A SINGLE TERMINAL (COMMON)
FOR LOW AND HIGH FIRE OPERATORS.
7. REFER TO CONTROL SUPPLEMENT FOR GROUND LEADWIRE ATTACHMENT.
IF ORIGINAL GROUND LEADWIRE AS SUPPLIED WITH THE APPLIANCE MUST BE REPLACED,
TYPE 125 C OR ITS EQUIVALENT MUST BE USED.
2. ALL WIRING EXTERNAL TO BOILER JACKET MUST BE:
A. U.S.A. - N.E.C. CLASS 1.
B. CANADA - C.S.A. C22.1 C.E.C. PART 1.
IGNITION CONTROL
PANEL TERMINAL.
8. WIRES ARE FACTORY INSTALLED TO CONTROL PANEL, BUT MUST BE FIELD
CONNECTED TO GAS VALVES AND FIRING RATE CONTROL TERMINALS (WHEN USED).
TRANSFORMER TERMINAL.
3. IF ORIGINAL WIRE AS SUPPLIED WITH THE APPLIANCE MUST BE REPLACED, TYPE 105 C OR
ITS EQUIVALENT MUST BE USED. EXCEPTION, SEE NOTE 7.
9. PILOT LEADWIRES ARE NOT FIELD REPLACEABLE. REPLACE PILOT ASSEMBLY IF NECESSARY.
FACTORY WIRED TO CONTROL -
FIELD WIRED TO GAS
VALVE OR FIRING RATE CONTROL.
10.
DENOTES FIELD INSTALLED CHASSIS GROUND.
4. REFER TO CONTROL COMPONENT INSTRUCTIONS PACKED WITH BOILER FOR
APPLICATION INFORMATION.
11. ALL CONTACTS SHOWN WITHOUT POWER APPLIED - OFF SHELF CONDITION.
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Part Number 550-141-916/1001
UniversalControlSystem –Naturalgas
EQUIPMENT
GROUND
(NOTE 10)
Figure 3
Wiring diagram
LADDER WIRING DIAGRAM
H
N
120 V.A.C.
HIGH
LIMIT
CONTROL
SERVICE SWITCH
(BY OTHERS)
OPERATING
CONTROL
LOW WATER
CUT-OFF
PRIMARY
R
C
24 V.A.C.
PRIMARY
R
24 V.A.C.
MAIN GAS VALVE HIGH FIRE
OPERATOR (NOTE 6)
FIRING RATE CONTROL
(WHEN USED)
MV
MV
MAIN GAS VALVE LOW FIRE OPERATOR
MV/PV
MV/PV
PV
MV/PV
PV
GND
(NOTE 6)
(BURNER)
PV
MV/PV
24V
(GND)
SECONDARY GAS VALVE
24V
MAIN FLAME SENSOR
SENSE
SPARK
NO. 1 BASE
MAIN FLAME PROVING MODULE
MV
MV/PV
PILOT SOLENOID VALVE
PV
HIGH GAS
PRESSURE
SWITCH
(WHEN USED)
(NOTE 5)
GND
(BURNER)
24V
(GND)
2
24V
1
PILOT FLAME SENSOR
SENSE
SPARK
PILOT BURNER
(NOTE 9)
NO. 1 BASE
PILOT PROVING MODULE
MAIN GAS VALVE HIGH FIRE
OPERATOR (NOTE 6)
FIRING RATE CONTROL
(WHEN USED)
MV
MV
MAIN GAS VALVE LOW FIRE OPERATOR
MV/PV
MV/PV
PV
PV
MV/PV
GND
(BURNER)
(NOTE 6)
PV
MV/PV
24V
(GND)
SECONDARY GAS VALVE
24V
MAIN FLAME SENSOR
SENSE
SPARK
NO. 2 BASE
MAIN FLAME PROVING MODULE
MV
MV/PV
PILOT SOLENOID VALVE
PV
GND
(BURNER)
24V
(GND)
2
24V
1
PILOT FLAME SENSOR
HIGH GAS
PRESSURE
SWITCH
SENSE
SPARK
(WHEN USED)
(NOTE 5)
PILOT BURNER
(NOTE 9)
NO. 2 BASE
PILOT PROVING MODULE
Intermittent Pilot
A United Dominion Company
Universal Control System
Steam or Water
6 thru 23
LGB
Weil-McLain
500 Blaine St.
Michigan City, IN 46360-2388
Natural Gas
550-101-131/0798WM
PART NUMBER
Part Number 550-141-916/1001
7
LG B-6 t o LG B-2 3 Series 2 – Control Supplement
III
Wirin g
– continued
Wiring Procedure
1. Determine right or left electrical supply wiring.
2. Attach electrical junction box(es) to inside jacket end panel. Screws and nuts are provided.
For dual base boilers,use offset nipples (provided) to connect junction boxes together,
then hang junction boxes by screwing top box to boiler jacket.See Figure 4,below.
3. Attach control transformer(s) to junction box(es).
4. Drill 1/8" hole in interior jacket panel midway between ignition control panel and left jacket
panel. Mount wire support clip using sheet metal screw (furnished).
5. Complete wiring per wiring diagram, Figure 3 (pages 6 and 7).
“Hot” side of line voltage to boiler must be wired directly to limit circuit,
then fed to transformer primary(ies). Dual Base:“R”terminal of
secondaries are to supply power to bases independently of each other. Do
not wire“R”terminals together.
6. Install pilot proving and main flame proving ground connections as shown in Figures 1
and 2 (page 3) and Figure 3 (pages 6 and 7). Route wires through wire support clip.
7. Canada only - attach chain between junction box(es) and transformer with S-hooks.
Figure 4
Junction box assembly
Screw Holes
dual base boilers
Junction Box
to Mount
Ba se 1
Junction Box
to Ja cket
Offset Nipples
(2)
Junction Box
Ba se 2
911BGLr0
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Part Number 550-141-916/1001
UniversalControlSystem –Naturalgas
IV
Op e ra t in g in s t ru c t io n s
Part Number 550-141-916/1001
9
LG B-6 t o LG B-2 3 Series 2 – Control Supplement
V
Ve rific a t io n t e s t in g
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.
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.
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.
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.
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.
10
Part Number 550-141-916/1001
UniversalControlSystem –Naturalgas
VI
Pa rt s lis t
– continued
Figure 5
Parts
drawing
8
9
7
12
14
3
1
4
5
11
13
10
6
2
91601
Part Number 550-141-916/1001
11
LG B-6 t o LG B-2 3 Series 2 – Control Supplement
Weil-McLain
500 Blaine Street
Michigan City, IN 46360-2388
12
Part Number 550-141-916/1001
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