Weil-McLain LGB-5 - Manual (Page 2)

LGB LGB LGB LGB LGB-4 -4 -4 -4 -4 & 5 5 5 5 5 • Control Supplement • UCS • Propane
2 Part Number 550-141-919/0304
1. Remove all burners from base box assembly. Remove 3.95 mm natural gas main burner orifices in manifold.
Install 2.40 mm propane main burner orifices. Use pipe dope sparingly only on male ends. Use pipe dope
compatible with propane gases. Do not overtighten orifices.
2. Install pilot burners. See Figure 1. Follow Table 1 for electronic pilot burner and standing pilot burner (Q327)
locations on manifold.
3. Install gas controls and ignition control as shown in Figure 3 on page 7 or Figure 4 on page 8. Use Propane
Control Carton, Number 4 and 5.
4. Attach pilot switch box to interior jacket panel (see Figure 3 or 4, pages 7 and 8). Connect thermocouple from
standing pilot to switch box. Cut 60" pilot tubing into 2 pieces to make connections from pilot valve to pilot
switch box and from pilot switch box to standing pilot.
5. Attach:
a. 550-223-710 label above or to the left of boiler operating instruction label. Place so that this label reads
first.
b. 550-223-796 label next to rating label.
c. Wiring diagram on door.
d. Canada only - mount rating plate on interior jacket panel.
6. Proceed to section III, Gas Piping.
1. These instructions are for use with Propane Control Carton Number 4 and 5.
2. Remove jacket door(s) and access panel.
3. Disconnect wiring and tubing from existing pilot burner.
4. Remove all burners. Remove 3.95 mm natural gas main burner orifices in manifold. Install 2.40 mm propane
main burner orifices. Use pipe dope sparingly only on male ends. Use pipe dope compatible with propane
gases. Do not overtighten orifices.
5. Remove and discard existing electronic pilot burner from pilot burner tube. Replace with electronic pilot
burner in carton.
6. Attach Q327 standing pilot to burner tube in kit. Connect pilot tubing and thermocouple to pilot.
7. Re-install burners. See Table 1 for location of pilot burners.
8. Attach pilot switch box to jacket. See Figure 3 or 4, pages 7 and 8. Connect thermocouple to pilot switch box.
Cut 60" pilot tubing into 2 pieces to make connections from tee in pilot line to pilot switch box and from pilot
switch box to standing pilot.
9. Remove natural gas valve train.
10. Install propane gas valve train and fittings from carton. (See paragraph 4, page 3 of this Supplement.)
11. Re-install access panel(s).
12. See Figure 3 or 4, pages 7 and 8, for propane piping.
13. Wire per wiring diagram, pages 4 – 5. Add splices as needed.
Attach:
a. 550-223-710 label above or to the left of boiler operating instruction label. Place so that this label reads
first.
b. 550-223-796 label next to rating label.
c. Wiring diagram over diagram on door (one on each base).
14. To place in operation, follow instructions on constant burner pilot light-up label and boiler operating label.
15. Replace jacket doors.
I
New installation
Conversion from natural gas to propane gas
II
Existing installation
Conversion from natural gas to propane gas
This conversion is to be installed by a Weil-McLain distributor or other qualified agency in
accordance with the manufacturer's instructions and all codes and requirements of the
authority having jurisdiction. Failure to follow instructions could result in serious injury or
property damage. The qualified agency performing this work assumes responsibility for this
conversion.
For your safety, turn off electrical power supply before making any electrical connections to
avoid possible electrical shock hazard.