Navien NCB-180, Руководство по установке и эксплуатации

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40 Venting the Boiler
5.2 Selecting Vent Pipe Materials
Venting requirements differ in the US and Canada. Consult the
following chart or the most recent edition of ANSI Z223.1/NFPA
54 or CAN/CGA B149.1, as well as all applicable local codes and
regulations when selecting vent pipe materials. Do not use cellular
core based pipe materials for the exhaust vent.
Locale Recommended Vent Materials
USA
●
PVC Schedule 40 (Solid Core)
●
CPVC Schedule 40 or 80 (Solid Core)
●
Approved Polypropylene
Canada*
●
Type BH Special Gas Vent Class IIA (PVC)
●
Type BH Special Gas Vent Class IIB (CPVC)
●
Type BH Special Gas Vent Class IIC
(Polypropylene)
* For installation in Canada, field-supplied plastic vent piping must comply
with CAN/CGA B149.1 (latest edition) and be certified to the Standard
For Type BH Gas Venting Systems, ULC-S636. Components of this listed
system must not be interchanged with other vent systems or unlisted
pipes or fittings. All plastic components and specified primers and glues
of the certified vent system must be from a single system manufacturer
and must not be intermixed with another system manufacturer’s parts.
The supplied vent connector and vent termination are certified as part of
the boiler.
CAUTION
●
This boiler has a built-in control to limit the exhaust
temperature to 149°F (65°C). As a result, the boiler can be
vented with Schedule 40 PVC.
●
In high temperature applications, the exhaust temperature
can exceed 149°F (65°C). In that case, you must use Schedule
40 or 80 CPVC or Approved Polypropylene in the USA
or Type BH Special Gas Vent Class IIB (CPCV) or Class IC
(Polypropylene) that conforms to ULC-S636 in Canada.
If you require that return water hotter than 140°F (60°C) to circulate
back to boiler, the DIP switch must be configured (Dip Switch 2,
switch #8 to ON position). Otherwise, the boiler will control and
maintain the flue and DHW temperature below 150°F (65°C) and
140°F (60°C) respectively.
Note
●
When PCB DIP switch 2 #8 is set to Off (factory
default), the boiler does not operate without an
exhaust thermostat installed.
●
When you set PCB DIP switch 2 #8 to On, ensure
that CPVC piping is used for exhaust venting.
1 2 3 4 5 6
ON
1 2 3 4 5 6 7 8
ON
5.3 Measuring Vent Length
The maximum vent length when using 2 in exhaust ducts is 60 ft
(18 m). The maximum vent length when using 3 in vent ducts
is 150 ft (45 m). The intake duct length may be identical to the
exhaust duct length. Maximum vent lengths reduces according to
the number of elbows used, as shown in the following table:
Vent Size
Maximum
Length
Maximum
# of Elbows Equivalent Lengths
2 in 60 ft (18 m) 6
Reduce the
maximum vent
length accordingly
for each elbow used:
●
Each 90° elbow
equates to 8 linear
feet of vent
●
Each 45° elbow
equates to 4 linear
feet of vent
3 in 150 ft (45 m) 8
Reduce the
maximum vent
length accordingly
for each elbow used:
●
Each 90° elbow
equates to 5 linear
feet of vent
●
Each 45° elbow
equates to 3 linear
feet of vent
Note
●
The Maximum Length does not include any elbows.
●
If using a concentric termination as shown on
page 42, count this as 5 linear feet (1.5 m) of vent.