Installation Manual

30
WHL-019 REV. 12.17.14
For each floor containing bedroom(s), a carbon monoxide detector and alarm shall be placed in the living area outside the bedrooms,
as well as in the room that houses the heater. Detectors and alarms shall comply with NFPA 720 (latest edition). Failure to comply with
requirements for detectors and alarms could result in property damage, severe personal injury, or death.
E. EXHAUST VENT AND INTAKE PIPE SIZING
1. The exhaust vent and intake pipe size is 2" for the 100 and 130kBTU models and 3" for the 160 and 199kBTU models.
2. The maximum total equivalent length of 2” exhaust vent and intake pipe must not exceed 85 feet. The total maximum equivalent
length of 3” exhaust vent and intake pipe must not exceed 200 feet.
a. The equivalent length of elbows, tees, and other fittings are listed in the Friction Loss Table, Table 5:
FRICTION LOSS EQUIVALENT IN PIPING AND FITTINGS
FITTINGS OR PIPING
EQUIVALENT FEET
2”
3”
4”
90 DEGREE ELBOW*
5’
5’
3’
45 DEGREE ELBOW
3’
3’
1’
COUPLING
0’
0’
0’
AIR INLET TEE
0’
0’
0’
STRAIGHT PIPE
1’
1’
1’
CONCENTRIC VENT KIT
3’
3’
N/A
V500 2” VENT KIT
1’
N/A
N/A
V1000 3” VENT KIT
N/A
1’
1’
V2000 4” VENT KIT
N/A
1’
1’
Table 5 - *Friction loss for long radius elbow is 1 foot less. NOTE: Consult Polypropylene venting instructions for friction loss and pressure
drop equivalents.
b. For example: If the exhaust vent has two 90° elbows and 10 feet of PVC pipe we will calculate:
Exhaust Vent Equivalent Length = (2x5) + 10 = 20 feet.
Further, if the intake pipe has two 90° elbows, one 45° elbow and 10 feet of PVC pipe, the following calculation applies:
Intake Pipe Equivalent Length = (2x5) + 3 + 10 = 23 feet.
Finally, if a concentric vent kit is used we find:
Total Equivalent Length = 20 + 23 + 3 = 46 feet.
The total equivalent length is 46 feet which is well below the maximum of 85 feet.
3. The minimum total equivalent length is 16 equivalent feet.
Failure to provide a minimum total vent length of 16 equivalent feet could result in property damage and improper product operation.
F. LONGER VENT RUNS
The maximum total equivalent length can be extended by increasing the diameter of both exhaust vent and intake pipe equally.
However, the transitions should begin a minimum of 15 total equivalent feet from the water heater.
a. The maximum total equivalent length for increased diameter vent pipes is 125 feet for 2” transitioning to 3” pipe
(this number includes the minimum 15 total equivalent feet necessary for transition), and 200 maximum total
equivalent feet for 3” transitioning to 4” pipe (including the minimum 15 total equivalent feet necessary for
transition).
b. Transitions should always be made in vertical sections of pipe to prevent the condensate from pooling in the vent pipe.
kBTU
MAXIMUM TOTAL EQUIVALENT LENGTH AT
STANDARD VENT CONNECTION
REDUCING
COUPLING
MAXIMUM TOTAL EQUIVALENT LENGTH AT
MAXIMUM INCREASED VENT SIZE
100
130
85’ @ 2”
3” X 2”
125’ at 3”
160
199
200’ @ 3”
4” X 3”
200’ at 4”
Table 6 – Vent Sizing – Diameter and Length
c. If the transition occurs at a distance greater than 15 equivalent feet from the water appliance, the maximum equivalent
length will be reduced.