Installation Guide
27 Page
Determine the vent diameter (D) and the total vent length based on the number of water
height (H). See the table below.
Total vent length (L)="H"+"W"
Vent diameter="D"
WARNING
A Non-Return Valve must be installed for each water heater. This prevents
the escape of combustion gas through non-operating appliances.
For detailed instructions on the common-venting system, refer to the
instructions that are packaged with the vent parts or web site.
NOTICE
Regarding the clearances
between the exhaust
pp. 28
to 30.
Insert bird screen in
elbow terminals.
*Diameters of pipes are in accordance with Centrotherm's specifications.
**One elbow is equivalent to 5 ft (1.5 m) linear length, and the maximum number of elbows is 5.
Common-venting system
Vent
Diameter*
(D)
Max.
No.of
water
heaters
Max. Vertical and
Horizontal
(Total) Vent Length** (L)
DIP switch settings
540P Indoor
(Lower bank of
DIP switches)
4 in
(110 mm)
2 25 ft (7.6 m)
1 2 3 4 5 6 7 8
ON
No.3 : ON
No.4: OFF
5 in
(125 mm)
2 50 ft (15.2 m)
3 20 ft (6.1 m)
6 in
(160 mm)
2 100 ft (30.5 m)
3 75 ft (22.9 m)
4 50 ft (15.2 m
5 25 ft (7.6 m)
6 20 ft (6.1 m)
8 in
(200 mm)
3 100 ft (30.5 m)
4 100 ft (30.5 m)
5 85 ft (25.9 m)
6 65 ft (19.8 m)
7 50 ft (15.2 m)
8 41 ft (12.5 m)
10 in
(250 mm)
5 100 ft (30.5 m)
6 100 ft (30.5 m)
7 100 ft (30.5 m)
8 100 ft (30.5 m)
Installaon
Installaon Manual
"H"
Intake
Exhaust
"D"
Elbow terminal
Elbow terminal
"W"
Non-Return Valve
DO NOT adjust any
other DIP switches
except the No. 3 and
No. 4 of the lower bank
of DIP switches for the
common-venting sys-
tem. (Refer to p.24 for
the location of the DIP
switches.
Turn off the power sup-
ply to the water heater
before changing the
DIP switch settings.
Failure to observe
these warnings could
lead to carbon monox-
ide poisoning or death.
WARNING