Lennox EL296DFV Installation Instructions Manual page 58

Testing of Non-Direct Vent Applications
for Proper Venting and Sufficient Combus­
tion Air
WARNING
CARBON MONOXIDE POISONING HAZARD!
Failure to follow the steps outlined below for each
appliance connected to the venting system being
placed into operation could result in carbon monox­
ide poisoning or death.
The following steps shall be followed for each ap­
pliance connected to the venting system being
placed into operation, while all other appliances con­
nected to the venting system are not in operation.
After the EL296DFV gas furnace has been started, the fol­
lowing test should be conducted to ensure proper venting
and sufficient combustion air has been provided to the
EL296DFV as well as to other gas‐fired appliances which
are separately vented.
If a EL296DFV furnace replaces a Category I furnace
which was commonly vented with another gas appliance,
the size of the existing vent pipe for that gas appliance must
be checked. Without the heat of the original furnace flue
products, the existing vent pipe is probably oversized for
the single water heater or other appliance. The vent should
be checked for proper draw with the remaining appliance.
The test should be conducted while all appliances (both in
operation and those not in operation) are connected to the
venting system being tested. If the venting system has
been installed improperly, or if provisions have not been
made for sufficient amounts of combustion air, corrections
must be made as outlined in the previous section.
1 - Seal any unused openings in the venting system.
2 - Visually inspect the venting system for proper size and
horizontal pitch. Determine there is no blockage or re­
striction, leakage, corrosion, or other deficiencies
which could cause an unsafe condition.
3 - To the extent that it is practical, close all building doors
and windows and all doors between the space in which
the appliances connected to the venting system are lo­
cated and other spaces of the building.
4 - Close fireplace dampers.
5 - Turn on clothes dryers and any appliances not con­
nected to the venting system. Turn on any exhaust
fans, such as range hoods and bathroom exhausts, so
they will operate at maximum speed. Do not operate a
summer exhaust fan.
6 - Follow the lighting instruction to place the appliance
being inspected into operation. Adjust thermostat so
appliance will operate continuously.
7 - Use the flame of match or candle to test for spillage of
flue gases at the draft hood relief opening after 5 min­
utes of main burner operation.
8 - If improper venting is observed during any of the
above tests, the venting system must be corrected or
sufficient combustion/make‐up air must be provided.
The venting system should be re‐sized to approach
the minimum size as determined by using the ap­
propriate tables in appendix G in the current standards
of the National Fuel Gas Code ANSI-Z223.1/NPFA 54
in the U.S.A., and the appropriate Natural Gas and
Propane appliances venting sizing tables in the cur­
rent standard of the CSA-B149 Natural Gas and Pro­
pane Installation Codes in Canada.
9 - After determining that each appliance remaining
connected to the common venting system properly
vents when tested as indicated in step 3, return
doors, windows, exhaust fans, fireplace dampers
and any other gas‐burning appliance to their previous
condition of use.
Other Unit Adjustments
NOTE - See troubleshooting flow charts if any safety
switches are found to be open.
Primary Limit.
The primary limit is located on the heating compartment
vestibule panel. This limit is factory set and requires no ad­
justment.
Flame Rollout Switches (Two)
These manually reset switches are located on the front of
the burner box.
Pressure Switch
The pressure switch is located in the heating compartment
on the cold end header box. This switch checks for proper
combustion air inducer operation before allowing ignition
trial. The switch is factory-set and must not be adjusted.
Temperature Rise
Place the unit into operation with a second-stage heating
demand. After supply and return air temperatures have
stabilized, check the temperature rise. If necessary, adjust
the heating blower speed to maintain the temperature rise
within the range shown on the unit nameplate. Increase the
blower speed to decrease the temperature rise. Decrease
the blower speed to increase the temperature rise. Failure
to properly adjust the temperature rise may cause erratic
limit operation.
Electrical
1 - Check all wiring for loose connections.
2 - Check for the correct voltage at the furnace (furnace
operating). Correct voltage is 120VAC + 10%
3 - Check amp-draw on the blower motor with blower ac­
cess panel in place.
Motor Nameplate__________Actual__________
Exhaust and Air Intake Pipe
1 - Check exhaust and air intake connections for tightness
and to make sure there is no blockage.
2 - Is pressure switch closed? Obstructed exhaust pipe
will cause unit to shut off at pressure switch. Check ter­
mination for blockages.
3 - Obstructed pipe or termination may cause rollout
switches to open. Reset manual flame rollout switches
on burner box assembly if necessary.
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