CleaverBrooks 4WI, Operation, Service And Parts Manual

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750-211 (revised 2009)
Promethean Boilers, Model 4WI Manual 5-5
5.5 — Firing Preparations for No. 2 Oil (Series 100-200)
Observe the reading on the air pressure gauge. With no oil flow, the pressure should be a minimum of 7 psi.
FIGURE 5-4.
Burner Drawer with Air Pressure Gauge
If there is no pressure, determine the cause and correct it before proceeding. Check for obstructions in the air inlet
line, incorrect rotation (remember, air pump rotation is clockwise), or a loose oil nozzle or other leaks. If the pres-
sure is much higher without any oil flow, check for obstruction in the discharge line or at the oil nozzle.
The air pressure will increase when an oil flow exists. At low firing rate, the air pressure may rise to 12 psi or more.
After air flow has been verified, turn the burner switch off and return the run/test switch to the “run” position.
5.5 — Firing Preparations for No. 2 Oil (Series 100-200)
Prior to initial firing, oil flow and pressure should be established
and verified. Atomizing air pressure should also be established as
outlined in Section 5.4. The schematic flow diagram in Chapter 2
indicates the flow of fuel and atomizing air.
If the burner is a combination fuel model, be certain that the main
gas shutoff cock is closed and set the gas/oil selector switch to
“oil.” Insert the burner drawer gun into its most forward position
and latch it in place, closing the oil drawer switch.
FIGURE 5-5.
Oil Gun Locked in Firing Position
NOTE: Abnormally high pressure indicated on the nozzle air pressure gauge is an indication that the burner nozzle
has become clogged. In the event of clogging, check the nozzle and clean as necessary.
The air pressure should not exceed 35 psi at high-fire. Greater air pressure causes excessive wear of the air pump,
increases tube oil usage, and can overload the motor, thus causing damage to the equipment.
! Caution