High Air Pressure Switch Settings; To Set Combustion - CleaverBrooks CFC Operation, Service & Parts Manual

Section 4 — CFC Commissioning
Figure 4-10 Operation screen
4-24

To set combustion:

1. Check inlet gas pressure and reset low gas pressure switch.
2. At Operation screen set firing rate to low fire. Review burner
sequence before proceeding.
3. Turn LOCAL/REMOTE switch to LOCAL.
4. Initiate burner firing sequence. The burner switch is accessed
via the CB Falcon Operation page (Figure 4-10). If the burner
does not ignite, adjust choke counterclockwise slightly until you
can see a slight yellow flame at the burner during ignition.
Clockwise adjustments to the low-fire offset screw may also be
tried. Check that gas pressure to gas valve inlet is sufficient to
fire burner (see Table 4-3 for gas pressure requirements).
5. After burner lights, maintain in low fire position. At low fire,
using main choke on gas valve and a combustion analyzer set
O2 level within 3-8% O2.
6. Manually modulate the burner to high fire. Adjust the gas choke
if necessary to obtain desired O2% (6% - 7%).
7. Modulate to low fire and fine tune offset screw to obtain desired
O2% (6% - 7%).
Verify adjustments by modulating back and forth between low and
high fire.
While setting combustion observe gas pressure at low fire and at
high fire. Ensure pressure is within limits shown in Table 4-3.

9. High Air Pressure Switch settings

The High Air Pressure witch (HAPS) is used to safely shut down the
boiler in case of a blocked flue or blocked condensate condition.
The HAPS switch setting for each model CFC can be found below:
Table 4-5 HAPS Settings
Model
CFC-500
CFC-750
CFC-1000
CFC-1500
CFC-1800
CFC-2500
CFC-3300
The HAPS has a manual reset, similar to the High/Low gas pressure
switches.
Note: In the event of a HAPS lockout, investigate possible causes
before attempting to restart boiler.
Setting
3.5" W.C.
3.5" W.C.
3.5" W.C.
4.5" W.C.
4.5" W.C.
5.25" W.C.
5.75" W.C.
Part No. 750-263