Page 61
Unit Start Up
FOR YOUR SAFETY READ BEFORE OPERATING
 WARNING
Do not use this furnace if any part has been underwater. 
     
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. If overheating 
       
 CAUTION
Before attempting to perform any service or maintenance, 
turn the electrical power to unit OFF at disconnect switch.
BEFORE LIGHTING the unit, smell all around the furnace 
   
The gas valve on the EL297UHV is equipped with a gas 
control switch (lever). Use only your hand to moveswitch. 
Never use tools. If the the switch will not move by hand, 
do not try to repair it. Force or attempted repair may result 
Placing the furnace into operation:
EL297UHV units are equipped with an automatic hot 
surface ignition system. Do not attempt to manually light 
burners on this furnace. Each time the thermostat calls for 
heat, the burners will automatically light. The ignitor does 
not get hot when there is no call for heat on these units.
Priming Condensate Trap
The condensate trap should be primed with water prior 
to start-up to ensure proper condensate drainage. Either 
            
these steps to prime the trap:
1 -   Follow the lighting instructions to place the unit into 
operation.
2 -  Set the thermostat to initiate a heating demand.
3 -  
4 -   Adjust the thermostat to deactivate the heating 
demand.
5 -   Wait for the combustion air inducer to stop. Set the 
thermostat to initiate a heating demand and again 
6 -   Adjust the thermostat to deactivate the heating 
demand and wait for the combustion air inducer to 
stop. At this point, the trap should be primed with 
operation.
 WARNING
  
explosion may result causing property damage, personal 
injury or death.
Gas Valve Operation (Figure 66)
1 -   STOP!  Read the safety information at the beginning 
of this section.
2 -  Set the thermostat to the lowest setting.
3 -  
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 access panel.
6 -  
7 -  
smell gas, STOP! Immediately call your gas supplier 
from a neighbor’s phone. Follow the gas supplier’s 
instructions. If you do not smell gas go to next step.
8 -  Move gas valve switch to ON. See Figure 66.
GAS VALVE SHOWN IN ON POSITION
INLET PRESSURE POST
HIGH FIRE
ADJUSTMENT
(under cap)
MANIFOLD
PRESSURE TAP
LOW  FIRE
ADJUSTMENT
(under cap)
Figure 66 
9 -  Replace the access panel.
10 - Turn on all electrical power to to the unit.
11 - Set the thermostat to desired setting.
NOTE - When unit is initially started, steps 1 through 
11 may need to be repeated to purge air from gas 
line.
12 -  If the appliance will not operate, follow the 
service technician or gas supplier.
Turning O Gas to Unit
1 -  Set the thermostat to the lowest setting.
2 -  
be performed.
3 -  Remove the access panel.