Pentair MASTERTEMP 125 Installation And User Manual page 21

The allowable vent runs for each vent pipe diameter are different and can not be exceeded.
Each 90-degree elbow reduces the maximum horizontal vent run by 12 feet and each 45-degree elbow
in the vent run reduces the maximum vent run by 6 feet. See Table 5 on page 20 for the maximum vent
lengths using 90-degree and 45-degree elbows.
WARNING
Risk of fire or asphyxiation if vent is not assembled
according to manufacturer's instructions or
if vent parts from different manufacturers are
mixed. Vent parts from different manufacturers
ARE NOT interchangeable. Mixing parts from
more than one manufacturer may cause leaks or
damage to vent. When assembling a vent, pick one
manufacturer and be sure that all vent parts come
from that manufacturer and are specified by the
manufacturer for your system. Follow manufacturer's
instructions, local code requirements, National
Fuel Gas Code requirements (U.S.) or standards
CSA B149.1 and B149.2 (Canada) carefully during
assembly and installation.
Rev. B 8/14
Section 3. Installation Instructions
NOTE
Min. 10 Ft.
6" Minimum
Clearance to
Combustible
Materials
Class B Double Wall
Metal Vent Pipe
Metal Flue
Collar
Vent
Body
Typical Metal Vent Pipe Installation - U.S.
Figure 13. –
(Vertical – Negative Pressure)
Min. 2 Ft.
Min. 10 Ft. (3.3 M)
(.7 M)
6" (15 cm) Minimum
Clearance to Combustible
Materials
Double Wall
Metal Vent Pipe
Vent
Body
Figure 14. –
MASTERTEMP ® 125 Pool and Spa Heater Installation and User's Guide
Listed
Termination
Cap
Storm Collar
Flashing
Firestop
Support Vertical
Vent Pipe so
adapter does not
take weight of
pipe.
Approved
Termination
Cap
Storm Collar
Flashing
Firestop
Metal Flue
Double Wall
Collar
Metal Vent Tee
Support Vertical
Vent Pipe so
adapter does not
take weight of
pipe. Dispose
Condensate
of condensate
Drain w/trap
according to
local codes.
Typical Metal Vent Pipe Installation
Canada (Vertical – Negative Pressure)
21