Calculating Burner Amperage

Sometimes, questions arise about burner amperage ratings. Beckett residential burners have a UL maximum amperage (amp) rating on the burner label. This value enables flexibility, so the burner can be built with various components including: iron core ignition transformers, split-phase motors, higher horsepower motors, and other accessories that are outlined in our UL Construction Files.

For example, the AF, AFG, AFII, and NX burners have a UL label maximum rating of 5.8 amps. However, many burner specifications utilize components that total less than 5.8 amps. How can you quickly and easily calculate the total amp rating of your specific burner?

Calculating the total burner amperage value

Determine the sum of the amp ratings found on each component, or its rating label. [UL 296 – Standard for Oil Burners, 10th Edition, Clause 73.9 a – c, identifies how to determine the minimum circuit ampacity, wherein the full load rating of each motor, plus 25% of the largest motor, plus the “ratings of all other loads”, (i.e., all other burner components) is totalized. This provides a basis for the method we recommend].

Example of Calculating the Total Amp Rating for an AFG Burner
21805E Motor 1.7A From motor rating label
7505 GeniSys Control 0.1A From control bottom cover
746001 Igniter 0.26A From R. W. Beckett Engineering data – (See chart below)
CleanCut Solenoid Coil 0.075A From Suntec Industries Engineering data – (See chart below)
Total                  = 2.135A

This method combines the individual component amps to obtain the nominal amperage rating for the burner only. (See the chart below for amperage ratings where the component may be rated in Watts or Volt Amps. NOTE: This information was accurate at the time of publication. Please, refer to the component manufacturer’s latest revision rating label, data sheets, or contact the manufacturer directly to confirm any amperage rating that is in question).

Another acceptable method

Use an accurate multi-meter with an amprobe to measure the amps with the burner running at rated voltage and actual load conditions.  We hope this information is helpful, but, if you have additional questions, please contact our Technical Services at 800-645-2876.  Our staff is available from 8:00AM – 5:00PM Eastern Time.  Also, visit us online at:

RWB Part No. Igniters Volts/Hertz Amps
746001 120V Beckett Igniter – AF/AFG/NX 120/60 0.26
747501 120V Beckett Igniter – AFII 120/60 0.37
2184404 Beckett CleanCut w/Coil 120/60 0.075
21941 Beckett CleanCut XL w/Coil 120/60 0.075
22295 Danfoss BFP 11 R3 w/Coil 120/60 0.1
  Solenoid Valves    
2182602 Delta EV8FFNFB 120/60 0.1
21789 Combu E7-LUS 120/60 0.115
51950 A/C Ready Kit 40 VA – Heating Mode 120:24/60 0.08
51950 A/C Ready Kit 40 VA – Cooling Mode 120:24/60 1.86