Initial Start-Up Procedure; Gas Train And Piping - CleaverBrooks CFC-500 Operation, Service And Parts Manual

Section 4 — CFC Commissioning
I. INITIAL START-UP PROCEDURE
NOTE: For LP gas-fired units or boilers with optional dual-fuel gas
train, see section K - Procedures for LP gas.

1. Gas Train and Piping

The ClearFire burner is equipped with a combination servo-
regulated gas valve and venturi mixing unit. The gas valve consists
of a single body with dual solenoid shut off valves, filter screen, and
a built-in constant pressure gas/air servo controller. The blower
speed is controlled by the CB Falcon with airflow directly
proportional to the speed of the fan. The airflow creates a drop in
pressure due to the venturi effect. The modulating controller of the
valve actuator senses air pressure change and accordingly brings
about a change in the gas flow proportional to the air pressure. The
gas follows the airflow in a set ratio, so that fuel always matches
the air as the burner firing rate increases or decreases.
1. Check the gas delivery system to be sure it is properly piped and
wired.
2. Review available gas pressure to assure it is compatible with the
main gas regulators upstream of the Model CFC gas train. Note:
The maximum rated inlet pressure to the CFC gas train is 1/2
psig (14.0" WC). An upstream regulator and overpressure
protection are required if building supply gas pressure is
greater than 1/2 psig.
3. To bleed air from the supply pipe, open the manual gas shut off
valve upstream of the burner gas train and bleed air from the
piping by loosening the union in the upstream piping.
4. The burner and its gas connection must be leak tested before
placing the boiler into operation.
5. Gas Pressure Regulator - Using the adjusting screw on the main
gas regulator, adjust the inlet pressure to the recommended
levels in Table 4-3.
Figure 4-4 Premix Burner Technology - Full Modulation
4-18
Warning
!
Before initial startup, check for block-
ages in the flue venting or vent termi-
nations. Inspect the burner and
furnace for any contamination or
blockages.
Note: To measure supply pressure
at the CFC gas valve, use the
test port on the valve inlet
flange (see below). Do not
use the leak test cocks to
measure gas pressure.
Pressure
check
Part No. 750-263