AIR ADJUSTMENT
FIXED AIR BURNERS
Loosen the locking screw and move the arm (B) along the scale (C) to the position wanted and tighten the screw. Check the air adjustment by making a flue gas analysis.
Figure 9-4
AIR ADJUSTMENT
VARIABLE AIR BURNERS
Adjust first air shutter by loosening locking screw and move arm (B) along scale (C) to give best flame signal strength and most consistent light-off with pilot pressures set. Set second shutter linkage by installing linkage rod into ball joints of modulating motor and air damper shaft arm. With damper closed and modulating motor in full down position, set ball joints secured. Observe combustion reading through full range of modulation. Adjust as needed to obtain proper combustion efficiencies with carbon monoxide-free combustion. Make all adjustments with linkage in the low fire position. CAUTION: Do not allow the modulating motor to push the air damper past the full open or full closed position while making adjustments. Damage will occur. Record damper positions from indicator dials and hold linkage rod in ball joint with fingers as motor actuates to eliminate this risk. After correct damper movement is determined, tighten ball joint screws.
Figure 9-5
BURNER MOTORS
No routine service is necessary on the blower system other than cleaning the blower wheel or oiling the motor when necessary. Blowers using three-phase motors will run in either direction depending on the connection of the power supply. On new installations, motor replacement or power supply disturbance, the rotation must be checked. Corrections can be made by interchanging any 2 wires of the three-phase power supply.
NOMOGRAPH FOR DETERMINING FLUE LOSSES FROM CO2 AND FLUE TEMPERATURE FOR NATURAL GAS
(STEADY STATE EFFICIENCY CAN BE DETERMINED FROM THE FLUE LOSS)
PV500-9 04-2000 | (6) | Section 9 |
