Installation Guide
Part number 550-100-066/0608
g a s -f i r e d w at e r b o i l e r — Boiler Manual
36
Sidewall vent/air termination: 3” PVC concentric
Termination kit — Weil-McLain 3” PVC concentric
termination
The Weil-McLain 3” PVC concentric termination kit must be pur-1.
chased separately. See Figure 101, page 93 for part number.
Use only the Weil-McLain 3” PVC concentric termina-
tion kit for concentric venting. Provide pipe adapters as
needed for 2” or 4” plastic piping or for AL29-4C vent
pipe.
Allowable vent/air pipe materials
Use only the materials listed in 1. Figure 32, page 31.
Maximum piping length
Locate the termination such that the total air piping and vent piping 1.
from the boiler to the termination will not exceed the maximum
length given in Figure 42.
Maximum lengths listed in 2. Figure 42 allow for 1 elbow. Additional
elbows required a reduction in maximum length as explained in
the table notes.
Connecting from termination to boiler
Install the termination as instructed in the following. Then pro-1.
ceed to page 48 to complete the air and vent piping between the
termination and the boiler.
The center lines between the air and vent are wider at the concentric 2.
termination connections than at the boiler. See Figure 60, page 45
for suggestions on adjusting the spacing when required. In addi-
tion to the method given there, you can rotate the Y-fitting slightly,
which will cause the air pipe to be slightly higher or lower than
the vent, but the center lines will match those at the boiler vent
and air connections.
Determine locations for terminations
A gas vent extending through an exterior wall shall not
terminate adjacent to the wall or below building exten-
sions such as eaves, parapets, balconies or decks. Failure
to comply could result in severe personal injury, death
or substantial property damage.
Locate the vent/air terminations using the following guidelines.1.
You must consider the surroundings when terminating the vent 2.
and air:
Position the vent termination where vapors will not damage a.
nearby shrubs, plants or air conditioning equipment or be
objectionable.
Feet Elbows Feet Elbows Feet Elbows
80 30 1 100 1
Not
allowed
105 30 1 100 1
155 Not allowed 100 1
230 Not allowed 30 1 70 1
310 Not allowed Not allowed 70 1
* Install pipe reducers to adapt from pipe size used to the 3.5 inch
outside diameter required at the termination. You do not have to
reduce allowable pipe length for the reducers.
Also install reduc-
ers as necessary where connecting to the boiler vent and air
connections.
You do not have to reduce allowable pipe length for the 45° elbow
used to connect to the air fitting on the concentric assembly.
For piping using more than 1 elbow, reduce maximum allowable
length:
• 7 feet for each additional 4-inch elbow (90° or 45°)
• 7 feet for each additional 3-inch long radius elbow
• 16 feet for each 3-inch short radius elbow
• 7 feet for each 3-inch 45-degree elbow.
Termination location — Weil-McLain vent/air
plate — height above grade or snow line