Venting & air — general, Gv90, Boiler manual – Weil-McLain GV90+ User Manual
Page 32: Gv90+ model maximum vent and air pipe lengths

Part number 550-142-054/0411
GV90+
gas
-
fired
water
boiler
— Boiler Manual
32
Venting & air — general
(cont.)
Figure 39
GV90+ venting and air piping — OPTIONS and PIPING LIMITS
Vent length affects boiler input — the boiler automatically derates to compensate for pressure loss through the vent.
See the derate values given in Figure 109, page 101. The longer the vent, the more the input is reduced.
GV90+ Model
Maximum vent and air pipe lengths
(Minimum length for all applications is 2 feet)
(All applications include allowance for the termination fittings)
DIRECT VENT
(combustion air piped to boiler from outside)
DIRECT EXHAUST
(combustion air from inside)
SIDEWALL
termination
VERTICAL
termination
SIDEWALL
termination
VERTICAL
termination
Weil-McLain
vent/air cap
3” PVC
Separate pipes
3” PVC
Concentric
[Note 1]
3” PVC
Separate pipes
3” PVC
Concentric
[Note 1]
3” PVC
Coupling or
W-M Cap
3” PVC
Coupling
See page 37
See page 39
See page 41
See page 43
See page 45
See page 51
See page 53
Max.
Length
(feet)
Max.
Length
(feet)
Max.
Length
(feet)
Max.
Length
(feet)
Max.
Length
(feet)
Max.
Length
(feet)
Max.
Length
(feet)
-3
100
100
100
100
100
100
100
-4
100
100
100
100
100
100
100
-5
100
100
100
100
100
100
100
-6
100
100
100
100
100
100
100
Equivalent feet for elbows — deduct from maximum equivalent length of piping (does not apply to termination fittings)
• 7 feet per for each 3-inch 90° long-radius or 45° elbow
• 16 feet for each 3-inch short-radius elbow
Note 1:
Use only PVC pipe DO NOT use CPVC or ABS with concentric termination kits.
IPEX 3” PVC concentric vent kits can be used with standard PVC pipe, fittings and cement (ANSI/ASTM D1785) except where ULC
S636 compliance is required. For ULC S636 compliance, all pipe, fittings and cement must be IPEX System 636. When using IPEX
kits, use only IPEX product code 196006 for 3” venting.
Contact Weil-McLain for ordering information and availability of Weil-McLain venting kits.