MACH® Series
Gas-Fired Boiler
Installation
16
Conventional Vent Systems
The following termination clearance requirements are for conventional, non-direct vent installations.
•
The vent system shall terminate at least 3 ft above a forced air inlet within 10 feet horizontally.
•
The vent system shall terminate at least 4 ft below, 4 ft horizontally from or 1 ft above any door, operable window
or gravity inlet into any building. The bottom of the vent terminal shall be at least 12 in. above grade or highest
expected snow line (if applicable).
•
Through the wall terminations shall not terminate over public walkways or over an area where condensate or
vapor could create a nuisance or hazard or could be detrimental to the operation of regulators, relief valves or
other equipment.
Direct Vent (Sealed Combustion) Systems
•
The vent terminal shall be located at least 12 in. from any air opening into a building. The bottom of the vent
terminal shall be at least 12 in. above grade. Both the vent and air intake terminals must be at least 12 in. above
the highest expected snow line.
•
Through the wall terminations shall not terminate over public walkways or over an area where condensate or
vapor could create a nuisance or hazard or could be detrimental to the operation of regulators, relief valves or
other equipment.
Interior Component Installation
All vent system components shall be installed so as to maintain the following required minimum clearances:
Combustible
Non-Combustibles
Unlisted single wall metal pipe
Do NOT Use
Do NOT Use
Single wall CPVC/PVC pipe
Do NOT Use
Do NOT Use
UL 1738 listed Category IV vent
Per manufacturer’s listing
Per manufacturer’s listing
3.5.3.3 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 figures below. The boiler connector (provided) is designed to
accept a 10” OD nominal pipe. This connector incorporates provisions to drain condensate formed in the vent system
using a 3/4” OD drain stub. This drain stub should be connected with the condensate drain on the boiler. The
condensate drains shall have a 4” tall trap to prevent the passage of flue gases through the condensate system.
NOTICE!
Make sure that the weight of the vent is
not supported
by the boiler vent collar.
The collar is not
designed to support the weight of the vent.
Horizontal vent sections shall be supported in a manner to prevent
sags or low spots where condensate can collect. Structural supports must be connected to building elements of
sufficient strength to withstand the weight of the vent system and any bending forces imposed by the venting
system.