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Position:List of Measures»Stationary Sources-Other»Requirement for NOx Emission regarding domestic gas-combustion boiler

Stationary & Fugitive Sources
Requirement for NOx Emission regarding domestic gas-combustion boiler
Source Category Pollutants Related Authorities Cost Summary
Stationary Sources-Other NOx Local Government, Ministry of Industry and Information Technology TBD

This control measure would reduce oxide of nitrogen(NOx) emissions from domestic gas-combustion boilerthrough retrofit of low NOx burners.


Reduce NOx emissions from domestic gas-combustion boiler.


Natural gas firedfan‐type central furnaces are used in residential and commercial buildings toprovide comfort heating. Most single family homes and many multi‐unitresidences have this type of heating equipment. Typically, residential unitshave burners rated between 50,000 and 175,000 British thermal units per hour(Btu/hr) and generate 75 to 100 ppm or more NOx. Low NOx burners have beendeveloped for many types of combustion equipment. These burners have beensuccessfully retrofitted to large process heaters and boilers, and are now beingdesigned for smaller combustion devices like residential water heaters. Theselow NOx burners can achieve NOx emissions of 14ng/joule (approximately 20 ppm)of delivered heat for large water heaters.

Expected Results

Emission Reduction

Pollutants  (tons per day)






The emissionreductions from this measure will be phased in as existing furnaces are replacedover the coming 15‐20 years. Emission reductions are expected to be 1.2 tonsper day NOx when the measure is fully implemented.

Exposure Reduction



There are potentialpositive benefits of reduced greenhouse gases through improved thermalefficiency of space heating, and potential combined efficiency of space andwater heating through re‐design of the building energy use systems.

Emission ReductionTradeoffs:

Dependingon the technology selected, NOx reductions may increase GHG emissions, specificallyCO2, by reducing efficiency of the process. However, low‐NOx burners of the sortused in similar applications do not tend to reduce the efficiency of theappliance noticeably. New forced air furnaces would likely be more efficientthan the ones they replace, reducing GHG emissions.

Related Authorities

Local Government, Ministry of Industry and Information Technology

Implementation Action

Current low NOx burner technology is capable of meeting 14ng/joule. This represents at least a 70 percent NOx reduction potential. This proposal includes retrofit, and domesticgas-combustion boiler. These large central furnaces have a life expectancy ofabout 30 years. This proposal assumes a retrofit strategy for existing largefurnace and space heaters. Implementation can take place over a reasonableperiod of 10 – 15 years, when the furnace reaches half of its potential lifespan.



Monitoring Mechanisms

Manufacturers of space heaters would be required to certify the heater toa NOx limit of 14ng/joule. Only certified heaters could be sold in theDistrict.


1.     San Joaquin Valley Ozone Plan, Page 405 – 406,Natural Gas‐Fired, Fan‐Type Residential Central Furnaces (S‐COM‐10)