Installation Manual

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Specifications subject to change without notice.
Piping should be pressure and leak tested in accordance with the
current addition of the NFGC in the United States, local, and
national plumbing and gas codes before the furnace has been
connected. Refer to current edition of NSCNGPIC in Canada.
After all connections have been made, purge lines and check for
leakage at furnace prior to operating furnace.
NOTE: The furnace gas control valve inlet pressure tap
connection is suitable to use as test gauge connection providing
test pressure DOES NOT exceed maximum 0.5 psig (14--In. W.C.)
stated on gas control valve. See Fig. 64.
If pressure exceeds 0.5 psig (14--In. W.C.), gas supply pipe must be
disconnected from furnace and capped before and during supply
pipe pressure test. If test pressure is equal to or less than 0.5 psig
(14--In. W.C.), turn off electric shutoff switch located on furn ace
gas control valve and accessible manual equipment shutoff valve
before and during supply pipe pressure test. After all connections
have been made, purge lines and check for leakage at furnace prior
to operating furnace.
The gas supply pressure shall be within the maximum and
minimum inlet supply pressures marked on the rating plate with
the furnace burners ON and OFF.
Gas entry can be from left or right side, or top panel. See Figs. 29
and 30.
Gas Pipe Grommet
For direct vent (2-pipe) applications, the knockout for the gas pipe
must be sealed to prevent air leakage. Remove the knockout, install
the grommet in the knockout, then insert the gas pipe. The
grommet is included in the loose parts bag. See Fig. 29.
FURNACE MAY NOT OPERATE HAZARD
Failure to follow this caution may result in intermittent
furnace operation.
Furnace control must be grounded for proper operation or
else control will lock out. Control must remain grounded
through green/yellow wire routed to gas valve and manifold
bracket screw .
CAUTION
!
ELECTRICAL CONNECTIONS
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD
Failure to follow safety warnings could result in
dangerous operation, serious injury, death or property
damage.
Improper servicing could result in dangerous operation,
serious injury , death or property damage.
-- Before servicing, disconnect all electrical power to
furnace.
-- When servicing controls, label all wires prior to
disconnection. Reconnect wires correctly.
-- Verify proper operation after servicing.
-- Always reinstall access doors after completing service
and maintenance.
!
WARNING
ELECTRICAL SHOCK HAZARD
Failure to follo w this warning could result in personal
injury or death.
Blower door switch opens 115--v power to control. No
component operation can occur. Do not bypass or close
switch with blower door removed.
!
WARNING
See Fig. 32 for field wiring diagram showing typical field 115--v
wiring. Check all factory and field electrical connections for
tightness.
Field--supplied wiring shall conform with the limitations of 63_F
(33_C) rise.
A11401
Fig. 32 -- Typical Two-- Stage Field Wiring Diagram