Low nox gas burner with cooled flue gas recycle
US-2026036297-A1 · Feb 5, 2026 · US
Arrangements of valves or dampers before the fire
Arrangements of valves or dampers before the fire · Cooperative Patent Classification (CPC)
Engines, pumps, lighting, heating, and mechanical systems.
Related technology areas
Mapped technology topics for this CPC code.
| Metric | Value |
|---|---|
| CPC code | F23L3/00 |
| Official title | Arrangements of valves or dampers before the fire |
| Display label | Arrangements of valves or dampers before the fire |
| Total patents | 32 |
Filing trend
Year-over-year patent counts classified under this CPC code.
Filing activity over the last five years is growing.
| Year | Patents |
|---|---|
| 2015 | 3 |
| 2017 | 3 |
| 2018 | 1 |
| 2020 | 2 |
| 2021 | 2 |
| 2022 | 6 |
| 2023 | 6 |
| 2024 | 5 |
| 2025 | 3 |
| 2026 | 1 |
Representative patents
Representative publications under this CPC code from precomputed stats, or recent filings when stats are unavailable.
Gas furnace and air conditioner having the same
US-12467660-B2 · Nov 11, 2025 · US
Low NOx gas burner with cooled flue gas recycle
US-12460814-B2 · Nov 4, 2025 · US
Indexed vent for natural draft cooking devices
US-12247744-B2 · Mar 11, 2025 · US
Systems and methods for extending the turndown ratio of gas-fired burner systems
US-12092328-B2 · Sep 17, 2024 · US
Fluid heating system with combustion trim learning
US-2024110728-A1 · Apr 4, 2024 · US
Arrangement having two burners
US-11920785-B2 · Mar 5, 2024 · US
Fluid heating system with combustion trim learning
US-11885531-B2 · Jan 30, 2024 · US
Oven gas burner shutter with ducted inlet
US-11859830-B2 · Jan 2, 2024 · US
Systems and Methods for Extending the Turndown Ratio of Gas-Fired Burner Systems
US-2023304662-A1 · Sep 28, 2023 · US
Systems and methods for extending the turndown ratio of gas-fired burner systems
US-11703224-B2 · Jul 18, 2023 · US
Low nox gas burner with cooled flue gas recycle
US-2023213182-A1 · Jul 6, 2023 · US
Low nox gas burner with cooled flue gas recycle
US-2023213181-A1 · Jul 6, 2023 · US
Gas furnace and air conditioner having the same
US-2023147831-A1 · May 11, 2023 · US
Radiant tube burner, radiant tube, and method of designing radiant tube burner
US-2023054425-A1 · Feb 23, 2023 · US
Exhaust-gas tract for a motor vehicle
US-11525379-B2 · Dec 13, 2022 · US
Heat source device
US-11512874-B2 · Nov 29, 2022 · US
Fluid heating system with combustion trim learning
US-2022349622-A1 · Nov 3, 2022 · US
Indexed vent for natural draft cooking devices
US-2022196244-A1 · Jun 23, 2022 · US
Oven gas burner shutter with ducted inlet
US-2022154936-A1 · May 19, 2022 · US
Frequently asked questions
Answers are generated from the same data shown on this page.
- What is CPC F23L3/00?
- CPC F23L3/00 is the Cooperative Patent Classification code for “Arrangements of valves or dampers before the fire.”
- How many patents are filed under CPC F23L3/00 (Arrangements of valves or dampers before the fire)?
- Our database includes 32 publications tagged with this CPC code.
- Is patent activity under CPC F23L3/00 growing?
- Publication counts under this code: 5 in 2024 vs 3 in 2025 (latest complete years).