Resize the common venting system to the minimum vent pipe size determined by using the appropriate tables in Appendix G. (These are in the current stan dards of the National Fuel Gas Code ANSI Z223.1.
CHIMNEY |
| REPLACING FURNACE THAT |
OR GAS |
| WAS PART OF A COMMON |
VENT |
| VENT SYSTEM |
(Check sizing |
|
|
for water |
|
|
heater only) |
|
|
|
|
|
FURNACE | WATER |
(Replaced | HEATER |
by EL296) |
|
| OPENINGS |
| (To Adjacent |
| Room) |
If an EL296UHE furnace replaces a furnace which was commonly vented with another gas appliance, the size of the existing vent pipe for that gas ap pliance 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.
FIGURE 21
Exhaust Piping (Figures 22, 24 and 25)
Route piping to outside of structure. Continue with installa
tion following instructions given in piping termination sec
tion.
CAUTION
Do not discharge exhaust into an existing stack or stack that also serves another gas appliance. If verti cal discharge through an existing unused stack is re quired, insert PVC pipe inside the stack until the end is even with the top or outlet end of the metal stack.
CAUTION
The exhaust vent pipe operates under positive pres sure and must be completely sealed to prevent leak age of combustion products into the living space.
Vent Piping Guidelines
The EL296UHE can be installed as either a
NOTE - In Non‐Direct Vent installations, combustion air is taken from indoors or ventilated attic or crawlspace and flue gases are discharged outdoors. In Direct Vent installations, combustion air is taken from outdoors and flue gases are discharged outdoors.
Intake and exhaust pipe sizing
In some applications which permit the use of several differ ent sizes of vent pipe, a combination vent pipe may be used. Contact Lennox' Application Department for assis tance in sizing vent pipe in these applications.
NOTE - The exhaust collar on all models is sized to ac commodate 2” Schedule 40 vent pipe. In horizontal ap plications, any transition to exhaust pipe larger than 2” must be made in vertical runs of the pipe. Therefore a 2” elbow must be added before the pipe is transitioned to any size larger than 2”. This elbow must be added to the elbow count used to determine acceptable vent lengths. Contact the Application Department for more information concerning sizing of vent systems which include multiple pipe sizes.
Horizontal Installation Offset Requirements
Exhaust Pipe
12” Max. | 12” Min. |
Horizontal
Gas Furnace
NOTE - All horizontal runs of exhaust pipe must slope back to ward unit. A minimum of 1/4” (6mm) drop for each 12” (305mm) of horizontal run is mandatory for drainage.
NOTE - Exhaust pipe MUST be glued to furnace exhaust fittings.
NOTE - Exhaust piping should be checked carefully to make sure there are no sags or low spots.
FIGURE 22
TABLE 3
MINIMUM VENT PIPE LENGTHS
EL296UHE | MIN. VENT LENGTH* |
MODEL |
|
|
|
| 15 ft. or |
045, 070, 090, 110, 135 | 5 ft. plus 2 elbows or |
| 10 ft. plus 1 elbow |
|
|
*Any approved termination may be added to the minimum length listed.
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