The Preferred Retrofit Burner for Cleaver-Brooks™ Boilers

Upgrade your Performance

Although other companies provide "insert" burner solutions, the Preferred  Retrofit Burner dramatically reduces installation time. This solution does not require any modifications to the boiler door, combustion fan, or existing gas train connection to the boiler.

Our specialized API-Ranger burner and BurnerMate Universal controls will give you the ability to burn natural gas and No. 2 oil, as well as Renewable Fuel Oil, and Bio-Residual™ Oil.

Read about the Preferred retrofit burner and the improved Bates College performance here.

Capacity – 4 MMBTUH - 120 MMBTUH

Fuel – Natural gas, #2-#6 Oil, specialty fuels

NOx Levels – 30 PPM for Natural Gas

Turndown – 10:1 for Natural Gas; 8:1 for #2 oil

Recommended Boiler Type- Firetube

Recommended Uses (commercial or industrial) – Commercial or Industrial

Warranty  – We offer a 2 year parts and services warranty for our retrofit burner.


DISCLAIMER: Preferred Utilities is not an authorized re-seller or service provider of Cleaver-Brooks™, is not affiliated with or sponsored by, nor selling Cleaver-Brooks™ parts. Preferred Utilities products and services are not covered by or part of any warranties or sales terms of Cleaver-Brooks™.

  • Overview and Features
  • Specifications
  • Application
  • Documents
Overview and Features

The Preferred retrofit burner for Cleaver-Brooks™ boilers is designed to bolt to the existing boiler and reuse the existing boiler front door, intermediate housing, and forced draft fan. Burner excess air and turndown performance significantly improve with the Preferred Ranger burner, resulting in measurable fuel savings. The addition of a variable speed drive on the forced draft fan will provide significant electricity savings—especially on boilers that often fire at low load.

Our patented technology allows us to achieve low NOx and excess air at the same time.


Features include:

  • .5 – 2.0% excess O2 from 50 - 100% firing rate when firing natural gas.
  • The Preferred burner retrofit will bolt up to the existing boiler with no cutting or welding required. 
  • Gas and oil inlets are designed to minimize re-piping of the fuel trains.
  • BurnerMate Universal controls have been applied to many Cleaver-Brooks™ boilers. The enclosure is designed to fit in the same place as the existing control panel on most boilers.
  • Burner and controls upgrade can be designed to burn: natural gas, or No. 2 oil, as well as Renewable Fuel Oil (RFO), Bio Residual Oil (BRO) upon request.
  • Sustainable Fuels: burns Bio-Residual Oil and Renewable Fuel Oil
  • Increased Efficiency: Higher turndown, lower excess air
  • Simple Replacement: Uses original housing and fan
  • No Cutting or welding: custom-made fit
  • Lower emissions
  • Get a high performance burner that will save fuel and electricity!

Fuel Variety: No 2 through No 6 Fuel Oil, and/or natural gas.

Advanced Design: our engineers specifically designed this burner to eliminate field errors, reduce space requirements, and facilitate maintenance when needed.

High Efficiency: Incorporates VSD for control of FD fan speed, resulting in significant electrical reductions, regardless of the type of fuel burned

Low emissions: Natural Gas: Sub 30 ppm without FGR

Specification: Single burner: firetube

NOx Emissions: Natural gas: Less than 30 ppmc No. 2 Fuel oil: less than 90ppmc (maximum 0.01% FBN) without FGR. No. 6 fuel oil: less than 250 ppmc (maximum 0.3% FBN) without FGR.

Operation: Turndown: 10:1 on gas firing; 8:1 on oil firing.

Supply Pressure: The Ranger burner accommodates a wide variety of combustion applications and fuels. Specific information relating to fuel intended to be used, as well as pressure and temperatures, must be provided.



Typical Cleaver-Brooks™ Burner

Preferred Ranger Burner

Excess Air Levels (Natural Gas)



Excess Air Levels (No. 2 Oil)



Turndown (Natural Gas)



Turndown (No. 2 Oil)




Recommended Boiler Type – Cleaver-Brooks™ Firetube boilers with integral burners

Recommended Uses – Commercial or Industrial


The Preferred Retrofit Burner for Cleaver-Brooks™ Boilers Brochure

The Preferred Retrofit Burner for Cleaver-Brooks™ Boilers Brochure (Español)