Weil-McLain 155 Boiler User Manual


 
Part number 550-101-235/0903
9
GAS-FIRED WATER BOILER — Vent Supplement
Prepare wall penetrations
1. Air pipe penetration:
a. Cut a hole for the air pipe. Size the air pipe hole
as close as desired to the air pipe outside
diameter.
2. Vent pipe penetration:
a. Cut a hole for the vent pipe. For either
combustible or noncombustible construction,
size the vent pipe hole at least 0.4" larger than
the vent pipe diameter:
• 4" hole for 3" PVC
• 5" hole for 4" PVC
b. Insert a galvanized metal thimble in the vent
pipe hole as shown in Figure 6.
3. Use a sidewall termination plate as a template for
correct location of hole centers.
4. Follow all local codes for isolation of vent pipe
when passing through floors or walls.
5. Seal exterior openings thoroughly with exterior
caulk.
Figure 6 Sidewall termination assembly
Vent/air termination — sidewall
(continued)
4
Determine location
(continued)
6. Locate terminations so they are not likely to be
damaged by foreign objects, such as stones or balls,
or subject to buildup of leaves or sediment.
7. Do not connect any other appliance to the vent pipe
or multiple boilers to a common vent pipe.
Figure 4 Clearance to gravity air inlets
Figure 5 Clearance to forced air inlets