4. The Series PFC
TM
boiler, like all high efficiency, gas-fired
appliances, is likely to produce a vapor plume due to
condensation. Surfaces near the vent termination will
likely become coated with condensation.
5. The maximum combined vent and air inlet pipe length
for PFC-625 and PFC-750 boilers is 200 equivalent
feet (61 meters) for horizontal venting and 500
equivalent feet (152 meters) for vertical venting. Be
sure that the boiler is located such that the maximum
vent length is not exceeded.
6. Air Intake Pipe Location – Sidewall Venting:
a. Provide a minimum of 1 foot (30 cm) clearance
from the bottom of the air intake pipe above
expected snow accumulation level. Snow removal
may be necessary to maintain clearances.
b. Do not locate air intake pipe in a parking area
where machinery may damage the pipe.
c. If the vent pipe and air inlet pipe terminations
penetrate the wall at the same level the minimum
distance between them is 12” edge-to-edge.
d. For multiple boiler installations, the minimum
horizontal distance between the inlet of one
boiler to the exhaust of an adjacent boiler is 12”
edge-to-edge. In addition, the minimum vertical
distance between the exhaust and air inlet is 6”.
See Figure 3.1 for an illustration.
e. The exhaust outlet of the vent pipe should not be
angled any more than 5º from horizontal.
f. Precautions should be taken to prevent
recirculation of flue gases to the air inlet pipe of
the boiler or other adjacent appliances.
7. Sidewall Venting Configuration:
a. See Figure 3.2 for an illustration of clearances for
location of exit terminals of direct-vent venting
systems.
• This boiler vent system shall terminate at
least 3 feet (0.9 m) above any forced air inlet
located within 10 ft (3 m). Note: This does not
apply to the combustion air intake of a direct-
vent appliance.
VENTING & AIR INLET PIPING
This appliance uses a positive pressure venting
system. All joints must be sealed completely to
prevent leakage of flue products into occupied
spaces. Failure to do this may result in severe
personal injury, death or major property damage.
WARNING
Covering non-metallic exhaust venting material is
prohibited and may result in severe personal injury,
death, or major property damage.
WARNING
Figure 3.2: Exit Terminal Location for Mechanical Draft and Direct-Vent Venting Systems
10
If the maximum equivalent vent length is exceeded,
the maximum burner input rate may be reduced.
NOTICE
Maximize the horizontal and vertical spacing to the
greatest extent possible as shown in Figure 3.1.
Take into account prevailing on-site wind conditions
during planning as well.
NOTICE
Figure 3.1: Vent Pipe Spacing for Multiple
Series PFC
TM
Boilers
The values shown in Figure 3.1 are the minimum
allowable spacing for intake and exhaust piping.
Steps should be taken in all cases to locate the
air intake and exhaust points with the maximum
allowable spacing the installation space can
accomodate.
NOTICE
