lp-657 Rev. 001 Rel. 000 Date 12.10.18
29
Friction Loss Equivalent in Piping and Fittings
Fittings or Piping
Equivalent Feet
3”
4”
6”
90 Degree Elbow*
5’
3’
3’
45 Degree Elbow
3’
3’
2’
Coupling
0’
0’
0’
Air Inlet Tee
0’
0’
0’
Straight Pipe
1’
1’
1’
Concentric Kit
3’
N/A
N/A
V Series Vent Kit
1’
1’
1’
AL20 4c Vent Terminal
1’
1’
1’
Table 11 - Vent Size and Total Equivalent Length
F. Longer Vent Runs
The maximum total equivalent length can be extended by
increasing the diameter of both the exhaust vent and intake pipes
equally. However, the transitions should begin a minimum of 16
equivalent feet from the boiler. Transitions should always be made
in vertical sections of pipe to prevent the condensate from pooling
in the vent pipe.
On all models EXCEPT the 285 model, the maximum equivalent
length for increased diameter vent pipes is 275 ft, which includes
16 ft from with boiler with a transition total of 259 ft upsize piping
for longer vent runs. On the 285 model, the maximum equivalent
length for increased diameter vent pipes is 250 ft., which includes
the 16 ft from the boiler with a transition total of 234 ft upsize piping
for longer vent runs.
Standard
Vent Connection
Reducing
Coupling
Increased Vent Size
3”
4” x 3”
4”
4”
6” x 4”
6”
6”
8” x 6”
8”
Table 12 - *Friction loss for long radius elbow is 1 foot less. NOTE:
Consult Polypropylene venting instructions for friction loss and
pressure drop equivalents.
Do not exceed the maximum lengths for vent pipes. Excessive
length could result in boiler shutdown and property damage.
G. Exhaust Vent and Intake Pipe Installation
All joints of positive pressure vent systems must be sealed
completely to prevent leakage of flue products into the living
space. Failure to do so could result in property damage, serious
injury, or death.
1. Use only solid PVC, CPVC, or stainless steel pipe or a Polypropylene
vent system approved for use with Category IV appliances.
FOAM CORE PIPING IS NOT APPROVED FOR EXHAUST VENT
APPLICATIONS. Foam core piping may be used on air inlet piping
only
.
2. Remove all burrs and debris from joints and fittings.
3. When using PVC or CPVC pipe, all joints must be properly cleaned,
primed, and cemented. Use only cement and primer approved for
use with the pipe material. Cement must conform to ASTM D2564
for PVC and ASTM F493 for CPVC pipe.
NOTE: DO NOT CEMENT
POLYPROPYLENE PIPE.
4. Ensure the vent is located where it will not be exposed to
prevailing winds.
5. In all roof venting applications, exhaust discharge must point
away from the pitch of the roof.
6. If the exhaust vent is to be terminated in a walled off area (such
as a roof with a parapet wall), ensure the exhaust vent terminates
a minimum of 10’ from nearest wall and extends level with or
above the top of the wall. This will ensure flue gas does does not
get trapped and possibly recirculated into the intake air pipe, which
could contaminate the combustion air.
7. To prevent water leakage, install adequate roof flashing where the
pipe enters the roof.
8. Do not locate vent over public walkways, driveways, or parking
lots. Condensate could drip and freeze, resulting in a slip hazard or
damage to vehicles and machinery.
9. Due to potential moisture build-up, sidewall venting may not
be the preferred venting option. To save time and cost, carefully
consider venting installation and location.
10. Horizontal lengths of exhaust vent must slope back towards the
boiler not less than ¼” per foot to allow condensate to drain from
the vent pipe.
11. The exhaust vent must terminate where vapors cannot make
accidental contact with people or pets, or damage shrubs or plants.
12. In vacant chimney applications, install and seal a rain cap over
existing chimney openings.
13. All piping must be fully supported. Use pipe hangers at a
minimum of 4 foot intervals to prevent sagging of the pipe where
condensate may form.
14. Do not use the boiler to support any piping.
15. Ensure the outdoor exhaust vent termination is screened to
prevent blockage caused by debris or birds.
16. Ensure the outdoor intake pipe termination is screened to
Failure to provide a minimum total vent length of 16 equivalent
feet could result in property damage and improper product
operation.
E. Exhaust Vent and Intake Pipe Sizing
1. The equivalent length of elbows, tees, and other fittings are listed
in the Friction Loss Table.
Total maximum equivalent length of increased diameter exhaust
vent and intake pipe must not exceed the lengths defined in this
manual. Failure to keep the total equivalent length below the
maximum lengths determined in this manual will result in faulty
boiler operation, substantial property damage, serious personal
injury, or death.
Figure 14 - Extended Vent Runs
Model Vent Size Maximum Total Equivalent Vent Length
285
3”
150 Feet
399
4”
200 Feet
Table 13 - Vent Run Transition
a. For example: If the exhaust vent is 3” in diameter, has two 90
o
elbows, and 10 feet of PVC pipe we will calculate:
Exhaust Vent Equivalent Length = (2x5) + 10 = 20 feet.
Further, if the 3” intake pipe has two 90
o
elbows, one 45
o
elbow,
and 10 feet of PVC pipe, the following calculation applies:
Intake Pipe Equivalent Length = (2x5) + 3 + 10 = 23 feet.
The total equivalent length is 43 feet, well below the maximum.
b. Effort should be made to keep a minimum difference in
equivalent length between the exhaust vent and intake pipe.
2. The minimum total equivalent length is 16 feet.
Summary of Contents for Elite FT EFT-285
Page 22: ...lp 657 Rev 001 Rel 000 Date 12 10 18 22 Figure 9 Piping Symbol Legend ...
Page 41: ...lp 657 Rev 001 Rel 000 Date 12 10 18 41 Figure 31 Internal Connection Diagram ...
Page 66: ...lp 657 Rev 001 Rel 000 Date 12 10 18 66 Figure 36 Cabinet Replacement Parts ...
Page 69: ...lp 657 Rev 001 Rel 000 Date 12 10 18 69 Maintenance Notes ...