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MACH® Gas-Fired Boiler
Page 20
3.5.3.5
Flue Connection
The boiler vent should not be connected into any portion of another mechanical
draft system without consulting the vent manufacturer. The boiler shall not be connected to any part of a
vent system serving a Category I or II appliance, nor shall a Category I or II appliance be connected to
any part of the vent system serving this appliance. Improper interconnection of venting systems may
result in leakage of flue gases into occupied spaces.
The connection from the boiler to the vent
should be as direct as possible and the upward
slope of any horizontal breaching should be at
least 1/4 inch per linear foot.
The complete exhaust with drain system is
shown in the figure below. The appliance
connector should incorporate provisions to
drain condensate formed in the vent system.
The connector shall include a drained boot tee,
a drained lateral tee or a horizontal or vertical
drain section.
NOTE! The condensate formed from
natural gas flue gases is acidic. The
condensate shall be drained in
accordance with local code requirements.
A condensate neutralizer may be required
by local code.