Specifications are subject to change without notice.
32
441 01 3400 02
e. Multiply gas rate (cu ft./hr) by heating value (Btuh/cu ft.)
to obtain input.
If clocked rate does not match required input from Step 1,
increase manifold pressure to increase input or decrease manifold
pressure to decrease input. Repeat steps b through e until correct
input is achieved. Reinstall regulator seal cap on gas valve.
5. Set temperature rise. The furnace must operate within the
temperature rise ranges specified on the furnace rating
plate. Do not exceed temperature rise range specified on
unit rating plate. Determine the temperature rise as fol-
lows:
NOTE
: Blower access door must be installed when taking
temperature rise reading. Leaving blower access door off will
result in incorrect temperature measurements.
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
Disconnect 115--v electrical power and install lockout tag
before changing speed tap.
!
WARNING
a. Place thermometers in return and supply ducts as close
to furnace as possible. Be sure thermometers do not see
radiant heat from heat exchangers. Radiant heat affects
temperature rise readings. This practice is particularly im-
portant with straight--run ducts.
b. When thermometer readings stabilize, subtract return--air
temperature from supply--air temperature to determine air
temperature rise.
NOTE
: If the temperature rise is outside this range, first check:
(1.) Gas input for heating operation.
(2.) Derate for altitude if applicable.
(3.) Return and supply ducts for excessive restrictions
causing static pressures greater than 0.50--In. W.C.
c. Adjust air temperature rise by adjusting blower speed. In-
crease blower speed to reduce temperature rise. Decrease
blower speed to increase temperature rise
d. Turn thermostat down below room temperature and re-
move blower access door.
e. To change motor speed selection for heating, remove
blower motor lead from control HEAT terminal (See Fig.
24.) Select desired blower motor speed lead from one of
the other terminals and relocate it to the HEAT terminal
(See Table 5 for lead color identification). Reconnect
original lead to SPARE terminal.
f. If the same motor speed tap is needed for heating and
cooling, a Jumper Wire accessory kit is available, see
Product Data sheet for the current Jumper Wire accessory
part number. The single wire end of the jumper will be
connected to the desired blower motor speed lead. The
two wire end of the jumper will be connected to the con-
trol board, connecting one wire to the HEAT (heating
blower tap) terminal and the other will be connected to
the COOL (cooling blower tap). Use the provided wire
ties to secure the loose blower motor speed lead and any
other loose wires, being careful not to put tension on any
wire connectors.
g. Repeat steps a through e.
h. When correct input rate and temperature rise is achieved,
turn gas valve ON/OFF switch to OFF.
i. Remove manometer or similar device from gas valve.
j. Reinstall manifold pressure tap plug in gas valve.
A06666
Fig. 41 -- Gas Control Valve
BURNER
ORIFICE
A93059
Fig. 42 -- Orifice Hole
FIRE HAZARD
Failure to follow this warning could result in personal
injury, death, and/or property damage.
Reinstall manifold pressure tap plug in gas valve to prevent
gas leak.
!
WARNING
FURNACE OVERHEATING HAZARD
Failure to follow this caution may result in reduced furnace
life.
Recheck temperature rise. It must be within limits specified
on the rating plate.
Recommended operation is at the
mid--point of rise range or slightly above.
CAUTION
!