Chimney And Vent Pipe Connection - Dunkirk XEB-2 Installation Manual

Low Design Water Temperature Systems
(Below 140° F) And Large Water Content
Systems:
!
WARNING
Significant condensation may form in this
boiler and/or the venting system if the boiler
is operated with return temperatures of less
than 120° F.
This condensation is corrosive and can eventu-
ally cause severe damage to the boiler and vent-
ing system. The minimum design return water
temperature to prevent this condensation in the
boiler and venting is 120°F. The minimum high
limit setting is 140°F.
If the boiler is to be used in a heating system
where design water temperatures below 140°F
are desired (e.g. radiant floor heating), a 3-way
or 4-way mixing valve or suitable alternative (e.g.
bypass piping, Figure #7) is required to prevent
low temperature (below return 120°F) return wa-
ter from entering the boiler. When using a mix-
for boilers for connection to gas vents or chimneys, vent installations shall be in
accordance with the National Fuel Gas Code, ANSI Z223.1- latest revision and applicable
provisions of the local building codes.
CHECK YOUR CHIMNEY
This is a very important part of your heating
system. It must be clean, the right size, properly
constructed and in GOOD CONDITION. No boiler
can function properly with a bad chimney.
1. Use local codes for installation or National Fuel
Gas Code Z223.1-latest revision. In Canada,
follow CSA B149.1 or .2 Installation Codes. It
is very important to properly size the venting
system for induced draft appliances. Consult
the Vent Sizing Tables, in the National Fuel
Gas Code ANSI Z223.1-latest revision for
correct sizing information. In Canada, consult
INStAllAtIoN-SYStem pIpING
!

ChImNeY ANd VeNt pIpe CoNNeCtIoN

ing valve, follow the manufacturer's installation
instructions.
If the boiler is to be connected to a system hav-
ing a large water content (such as a former grav-
ity system), it is suggested to use bypass piping
shown in Figure #7.
the Vent Sizing Tables, Amendment #1 to
CSA-B149.1 and .2 Installation Codes.
2. The boiler's induced draft blower has a 3"
outlet. A 3" X 4" increaser fitting is included in
the parts bag. Locate the increaser fitting on the
outlet of the induced draft blower, and secure
gastight with a bead of the furnished silicone
sealant. The increaser fitting is required on
this boiler for Category I venting, and 4" is the
minimum permissible vent diameter. This does
not imply that the vent connector is intended to
be 4" diameter pipe. The vent connector shall
be sized according to the appropriate venting
9
Figure #7