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IV−START-UP
A−Preliminary and Seasonal Checks
1 − Inspect electrical wiring, both field and factory installed for
loose connections. Tighten as required.
2 − Check voltage at disconnect switch. Voltage must be
within range listed on the nameplate. If not, consult the
power company and have voltage condition corrected
before starting unit.
B−Heating Start-Up
FOR YOUR SAFETY READ BEFORE OPERATING
WARNING
Do not use this furnace if any part has been underwa-
ter. A flood−damaged furnace is extremely danger-
ous. Attempts to use the furnace can result in fire or
explosion. Immediately call a qualified service tech-
nician to inspect the furnace and to replace all gas
controls, control system parts, and electrical parts
that have been wet or to replace the furnace, if
deemed necessary.
WARNING
Danger of explosion. Can cause injury
or product or property damage. Should
the gas supply fail to shut off or if
overheating occurs, shut off the gas
valve to the furnace before shutting off
the electrical supply.
CAUTION
Before attempting to perform any service or mainte-
nance, turn the electrical power to unit OFF at discon-
nect switch.
Priming Condensate Trap
The condensate trap should be primed with water prior to
start−up to ensure proper condensate drainage. Either
pour 10 fl. oz. (300 ml) of water into the trap, or follow
these steps to prime the trap:
1 − Follow the lighting instructions to place the unit into op-
eration.
2 − Set the thermostat to initiate a heating demand.
3 − Allow the burners to fire for approximately 3 minutes.
4 − Adjust the thermostat to deactivate the heating de-
mand.
5 − Wait for the combustion air inducer to stop. Set the ther-
mostat to initiate a heating demand and again allow the
burners to fire for approximately 3 minutes.
6 − Adjust the thermostat to deactivate the heating demand
and again wait for the combustion air inducer to stop. At
this point, the trap should be primed with sufficient wa-
ter to ensure proper condensate drain operation.
BEFORE PLACING THE UNIT INTO OPERATION,
the
unit, smell all around the furnace area for gas. Be sure to
smell next to the floor because some gas is heavier than
air and will settle on the floor.
The gas valve on the SLP98UHV is equipped with a gas
control switch. Use only your hand to move the control
switch. Never use tools. If the switch will not move by
hand, do not try to repair it. Force or attempted repair may
result in a fire or explosion.
Placing the furnace into operation:
SLP98UHV units are equipped with an automatic ignition
system. Do not attempt to manually light burners on this
furnace. Each time the thermostat calls for heat, the burn-
ers will automatically light. The ignitor does not get hot
when there is no call for heat on units with this ignition sys-
tem.
WARNING
If you do not follow these instructions exactly, a fire
or explosion may result causing property damage,
personal injury or death.
Gas Valve Operation (Figure 44)
1 −
STOP
! Read the safety information at the beginning of
this section.
2 − Set the thermostat to the lowest setting.
3 − Turn off all electrical power to the unit.
4 − This furnace is equipped with an ignition device which
automatically lights the burners. Do
not
try to light the
burners by hand.
5 − Remove the upper access panel.
6 − Move the gas valve switch to the
OFF
position. See
figure 44.
7 − Wait five minutes to clear out any gas. If you then smell
gas, STOP! Immediately call your gas supplier from a
neighbor’s phone. Follow the gas supplier’s instruc-
tions. If you do not smell gas go to next step.
NEGATIVE AIR
PRESSURE PORT
POSITIVE AIR
PRESSURE PORT
MANIFOLD
PRESSURE TAP
INLET
OUTLET
SUPPLY
PRESSURE
TAP
GAS VALVE SHOWN IN THE ON POSITION
FIGURE 44
