Model CFC
ClearFire Commercial Boilers
35
Rev. 05-2012
Table B5-24. Model CFC Minimum and Maximum Gas Pressure
Table B5-25. Model CFC Minimum Required Gas Pressure Altitude Correction
Boiler Room
Information
The boiler must be installed on a level non-combustible surface. If the surface is not
level, piers or a raised pad, slightly larger than the length and width of the boiler
base dimensions, will make boiler leveling possible. Installing the boiler on a raised
pad or piers will make boiler drain connections more accessible and will keep water
from splashing onto the boiler whenever the boiler room floor is washed.
Note: The pad or piers must be of sufficient load bearing strength to safely support the operating
weight of the boiler and any additional equipment installed with it. Approximate operating
weights are shown in Dimensions and Ratings.
Leveling
Once the boiler is placed, it must be leveled side to side and front to back using the
supply and return nozzles for horizontal and vertical positions. If shims are required
to level the boiler, the weight of the boiler must be evenly distributed at all points of
support. The legs may also be used for leveling.
Clearances
The boiler must be installed so that all components remain accessible; ensure no
overhead obstructions so the burner may be opened. Refer to Figure B5-28.
Boiler Model
Minimum pressure required at gas train connection
Max. pressure
Natural Gas
LP Gas
500
7" w.c.
11" w.c.
28” w.c.
750
7" w.c.
11" w.c.
1000
7" w.c.
11" w.c.
1500
10" w.c.
11" w.c.
1800
7" w.c.
11" w.c.
2500
9.5" w.c.
11" w.c.
3300
6.8" w.c.
11" w.c.
5 psi
Altitude in Feet
Correction Factor
Altitude in Feet
Correction Factor
1000
1.04
6000
1.25
2000
1.07
7000
1.3
3000
1.11
8000
1.35
4000
1.16
9000
1.4
5000
1.21
To obtain minimum required inlet pressure, select altitude of installation and multiply the pressure
shown in Table B5-24 by the correction factor corresponding to the altitude listed above.