CLEAN BURN CB-1400, Operator'S Manual

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Operator's Manual: Model CB-1400
8-2
Adjusting the Barometric Damper
NOTE: If the draft overfire is not in the -.02 to -.04 w.c. range, it is necessary to adjust the barometric
damper.
Figure 8B - Adjustment of Barometric Damper
1. Before starting the burner, turn the weight
on the flapper COUNTERCLOCKWISE
until the flapper remains closed. This will
provide maximum draft for the furnace.
2. Follow the directions in Section 6 to start
and adjust the burner.
3. With the burner running, check the draft
overfire with a draft gauge.
4. As shown in Figure 8B, adjust the weight
on the flapper to obtain a consistent
-.02 w.c. draft overfire. Turn the weight
COUNTERCLOCKWISE to increase draft
(i.e. draft increases as the flapper closes).
Turn the weight CLOCKWISE to decrease
draft (i.e. draft decreases as the flapper
opens).
5. Tighten the locking nut to securely hold
the weight in position.
Solving Draft Overfire Problems
WARNING! If you cannot achieve proper draft overfire, do not operate your furnace!
Contact your Clean Burn dealer for assistance.
ATTENTION: Backdraft must be resolved or your furnace will not operate correctly!
Under backdraft conditions, draft overfire readings will show positive pressure in the combustion
chamber.
Backdraft means that oil spray, combustion products, and heat are blown back against the
burner. Backdraft results in oil-fouled retention heads and electrodes. Severe backdraft will force heat
back against the burner and result in heat damage to the cad cell and transformer.
Backdraft is caused by the following conditions:
• Poor draft caused by improper stack design. (See Section 4.)
• Poor draft caused by improper adjustment of the barometric damper. (See Above)
• Incorrect combustion air band setting on the burner. (See Section 6.)
• Furnace flues are plugged with ash. (See Section 9.)
• Clean-out gasket on Clean-out door is out of position (See Section 9).
• Exhaust fans in your building are sucking gases down the stack. (See following pages)
TO OBTAIN PROPER
ADJUST THIS WEIGHT
TO OBTAIN PROPER
DRAFT OVERFIRE
I88572