34
The condensate line must remain unobstructed, allowing free flow of condensate. If condensate freezes
in the line, or if line is obstructed in any other manner, condensate can exit from boiler tee, resulting in
potential water damage to property.
When installing a condensate pump, select one approved for use with condensing boilers and furnaces.
The pump should have an overflow switch to prevent property damage from condensate spillage.
F. EXHAUST VENT AND INTAKE AIR VENT SIZING
1. The exhaust vent and intake air vent pipes are 4” for the Mod Con 300 and 500 and 6” for the Mod Con
850.
2. The total combined equivalent length of exhaust vent and intake air pipe should not exceed 200 feet.
a. The equivalent length of friction loss in elbows, tees, and other fittings are listed in Table 11.
FRICTION LOSS EQUIVALENT FOR STAINLESS OR PLASTIC PIPING AND FITTINGS
Table 11 – Friction Loss in Equivalent Feet - *Friction loss for long radius elbow is 1’ less.
b. For example: If the exhaust vent has two short 90
o
elbows and 10 feet of PVC pipe we will
calculate: Exhaust Vent Pipe Equivalent Length = (2x3) + 10 = 16 feet.
Further, if the intake air vent pipe has two short 90
o
elbows, one 45
o
elbow, and 10 feet of PVC
pipe, the following calculation applies: Intake Air Equivalent Length = (2x3) + 1 + 10 = 17 feet.
c. The intake air vent pipe and the exhaust vent are intended to penetrate the same wall or roof of
the building.
d. You should keep an equivalent length between the intake air vent pipe and the exhaust vent.
The minimum combined equivalent length is 16 to 32 maximum combined equivalent feet.
G. LONGER VENT RUNS
The maximum combined equivalent length can be
extended by equally increasing the diameter of both
the exhaust and intake air vent pipes. However, the
transitions should begin a minimum of 16 to 32
maximum combined equivalent feet from the boiler
equally on both the intake and exhaust.
To Next Page
Loading...
Need help?
General
