28
FIRE AND EXPLOSION HAZARD
Failure to follow this warning could result in personal
injury, death, or property damage.
Solvent cements are combustible. Keep away from heat,
sparks, and open flame. Use only in well ventilated areas.
Avoid breathing in vapor or allowing contact with skin or
eyes.
!
WARNING
In Canada, construct all combustion--air and vent pipes for this unit
of CSA or ULC listed schedule--40 PVC, PVC--DWV or
ABSDWV pipe and pipe cement. SDR pipe is NOT approved in
Canada.
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal
injury, death, or property damage.
All combustion--air and vent pipes must be airtight and
watertight. Pipes must also terminate exactly as shown in
Fig. 36 for direct vent (2--pipe) system or Fig. 37 for
ventilated combustion air option.
!
WARNING
An abandoned masonry chimney may be used as a raceway for
properly
insulated
and
supported
combustion--air (when
applicable) and vent pipes. Each furnace must have its own set of
combustion--air and vent pipes and be terminated individually, as
shown in Fig. 36 for Direct Vent (2--Pipe) system or Fig. 37 for
ventilated combustion air option.
A furnace shall not be connected to a chimney flue serving a
separate appliance designed to burn solid fuel.
Other gas appliances with their own venting system may also use
the abandoned chimney as a raceway providing it is permitted by
local code, the current edition of the National Fuel Gas Code and
the vent or liner manufacturer’s installation instructions. Care must
be taken to prevent the exhaust gases from one appliance from
contaminating the combustion air of other gas appliances. Do not
take combustion air from inside the chimney when using the
Ventilated Combustion Air option.
UNIT MAY NOT OPERATE HAZARD
Failure to follow this caution may result in intermittent unit
operation.
When vent pipe is exposed to temperatures below freezing,
such as when it passes through an unheated space or when a
chimney is used as a raceway, pipe must be insulated as
shown in Table 6 with Armaflex--type insulation.
CAUTION
!
Furnace combustion air and vent pipe connections are sized for 2--
in. pipe. Any pipe size change should be made outside furnace
casing in vertical pipe. The transition has to be made as close to the
furnace as reasonably possible. (See Fig. 38.)
58MV
C