Xcel Air Fuel / Gas Burner – 3422 3422 Fire All Dual-Fuel Burners are commonly used on heat treat and non-ferrous melting furnaces, kilns, ovens, air heaters, dryers, chemical process equipment, and other applications where superior temperature uniformity is required. These sealed-in, nozzle-mix burners for gas and/or distillate oil are stable on stoichiometric ratio, with large amounts of Xces air, or with up to 50% Xces fuel (provided additional air for combustion is in the furnace near the burner).


Burners can be lighted at rich, lean, or correct air/fuel ratio, then immediately turned to high fire. Required gas pressures are low: 2”wg at the burner for coke oven gas, less for natural gas. Required oil pressure at the burner is nearly zero, but a pressure drop of about 10psi should be taken across the Precise OilControl Valve.
The most common ratio control system for 3422 Burners uses a cross-connectedregulator and Ratio Controller. When appropriate for the application, flow balancing systems or fuel only control (see “Xces Air” paragraph) is very satisfactory. If furnace temperatures after shutdown rise above 1000oC, pass some air through burner to prevent overheating. During gas operation, use at least 7”wg atomizing air to cool atomizer (full atomizing air may be used); or for extended periods of operation on gas, atomizer can be withdrawn and stored: Use a back plate and gasket to seal rear of burner.


A Pilot Set normally is used to light 3422 Burners. On gas, direct spark ignition of the burner is available. A manual torch can be used in some pplications. Burners accept ultraviolet (UV) scanners for monitoring pilot or main flame. A flame rod can be used to monitor pilot or main gas fire. When using flame supervision, an interrupted pilot is required–do not use constant or intermittent pilots. If using direct spark ignition, turn off spark after burner lights. An observation port is furnished with all burners. Positions of pilot, flame detector, and observation port are interchangeable as long as pilot and flame detector are mounted in adjacent holes.


Xces air can improve temperature uniformity by avoiding hot spots in front of burners, by churning furnace atmosphere to reduce stratification, and by creating positive furnace pressure to eliminate cold air infiltration. Xces air can give very high effective burner turndown. Thus a furnace used for high temperature work (such as heat treating at 1000oC) with burners firing on air/fuel ratio can also be used for low temperature jobs (such as drawing or drying at 300oC) with burners firing on lean ratio.


The 3422 burners can be used with chamber temperatures upto 1100oC. If furnace temperature could rise above 850oC after shutdown, some air should be maintained through the burner to prevent over heating.


Air and gas inlets can be rotated in 90° (both CW & ACW Direction), but air and gas pipes should be brought in from the top or side to prevent oil dripping into them. Mounting plates are cast iron. Burner Blocks are 9″ long for thicker furnace walls, lining beyond end of tile should be flared at least 30° included angle, starting at tile OD. Extension tiles are not recommended. For installation convenience, burner body can be separated from the mounting plate and tile assembly. But burner block must be set in the wall with pilot and flame detector notches in proper location relative to intended burner body position.

JACKETED BURNER BLOCKS: 3422 Burners have a carbon steel jacket around the burner block for applications where there is no furnace refractory to support tiles and where temperatures.

List I. AIR CAPACITIES* Scfh (Standard Cubic Feet per Hour)
Burner designation 27”wg air at burner
3422-2A 2 600
3422-3A 4 100
3422-4A 6 300
3422-5A 10 300
3422-6A 15 700
3422-7AA 27 000
3422-8AA 33 500
3422-9AA 44 800
* Includes primary and secondary air.

List II. COMBUSTION AIR CAPACITITES in scfh (not including atomizing air)
Burner Designation Air Pressure Drop Across Burner in inches of WGP Approx. flame lengths in mm with 27”wg Main air (in open furnace)
1 2 8 10 14 21 28 Gas Oil
3422-2A 160 520 1160 1270 1470 1800 2100 152 456
3422-3A 280 890 1980 2160 2500 3050 3550 456 608
3422-4A 460 1450 3240 3540 4100 5000 5800 608 760
3422-5A 750 2370 5300 5800 6700 8150 9450 760 760
3422-6A 1180 3700 8300 9100 10500 12900 14800 912 1216
3422-7AA 2070 6550 14600 16000 18500 22700 26200 1824 1824
3422-8AA 2580 8150 18200 19900 23000 28200 32600 1824 1520
3422-9AA 3320 10500 23500 25800 29700 36400 42000 2128 1824

Burner Designation Air pressure drop across burner in inches of WGP
24 28 31 35 38 41
3422-2A, -3A,-4A 500 520 560 600 620 650
3422-5A 640 690 720 760 800 840
3422-6A 800 850 910 950 1000 1050
3422-7-AA, -8-AA 870 930 990 1040 1100 1150
3422-9-AA 2650 2840 3000 3170 3320 3580