Service manual

4
6 VENTING
Appliances for outdoor installation are intended
to vent using a listed vent cap.
For indoor installations venting must be in
accordance with Part 7, Venting of Equipment,
of the latest or current as amended National
Fuel Gas Code, ANSI Z223.1, or Section 7,
Venting of Equipment and Air Supply for
Appliances, of the latest or current as amended
CAN/CGA B149, Installation Codes, and
applicable provisions of the local building codes.
Vent connectors serving appliances vented by
natural draft shall not be connected into any
portion of mechanical draft systems operating
under positive pressure.
Horizontal runs of vent pipe shall be securely
supported (approximately every 4 feet) to
prevent sagging and maintain a minimum
upward slope of ¼” per foot from the appliance
to the vent terminal.
When an existing appliance is removed from a
common venting system, the common venting
system is likely to be too large for proper venting
of the appliances remaining connected to it. At
the time of removal of an existing appliance, the
following steps must be followed with each
appliance remaining connected to the common
venting system placed in operation, while the
other appliances remaining connected to the
common venting system are not in operation.
a) Seal any unused openings in the
common venting system.
b) Visually inspect the venting system for
proper size and horizontal pitch and
determine that there is no blockage,
restriction, leakage, corrosion or other
deficiency, which could cause an unsafe
condition.
c) Insofar as is practical, close all building
doors and windows and all doors
between the space in which the
appliances remaining connected to the
common venting system are located and
other spaces of the building. Turn on
clothes dryers and any appliances not
connected to the common venting
system. Turn on any exhaust fans, such
as range hoods and bathroom exhausts,
so they will operate at maximum speed,
do not operate a summer exhaust fan.
Close fireplace dampers.
d) Place in operation the appliance being
inspected. Follow the lighting
instructions. Adjust thermostat so that
appliance operates continuously.
e) Test for spillage at the draft control
device relief opening after 5 minutes of
main burner operation. Use the flame of
a match or candle or smoke from a
cigarette.
f) After it has been determined that each
appliance remaining connected to the
common venting system properly vents
when tested as outlined above, return
doors, windows, exhaust fans, fireplace
dampers and any other gas-burning
appliance to their previous condition of
use.
g) Any improper operation of the common
venting system must be corrected so
that the installation conforms to the
latest or current as amended National
Fuel Gas Code, ANSI Z223.1 or the
current CAN/CGA B149, Installation
Codes. When resizing any portion of the
common venting system, the common
venting system should be resized to
approach the minimum size as
determined using the appropriate tables
in Part 11 of the latest or current as
amended National Fuel Gas Code,
ANSI Z223, 1 or the current CAN/CGA
B149, Installation Codes.
Hydronic heating heat exchanger surfaces and
vent piping should be checked at least yearly for
deterioration and carbon deposits. Domestic hot
water heat exchanger surfaces and vent piping
should be checked every 6 (six) months.
Remove all soot or other obstructions from the
chimney and flue, which might impede draft
action. Replace any damaged or deteriorated
parts of the venting system.