F24H FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
Introduced: September 1968
Classification Context
- Section:
- MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- Class:
- HEATING; RANGES; VENTILATING
- Subclass:
- FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
Description
F24H encompasses fluid heating systems that generate heat through active means such as heat pumps, combustion, or electrical resistance to warm water, air, or other fluids for space heating, domestic hot water, and industrial applications. The subclass covers the overall design, integration, and operation of heater units combining heat sources with heat transfer mechanisms, including heat distribution networks and control systems. This classification excludes specific combustion chamber designs (covered in F23), dedicated heat exchanger elements (F28), and refrigeration cycles when classified outside heating contexts (F25). Related heating technologies employing passive solar collection or waste heat recovery are separately classified in their respective technology areas.
Filing statistics
IPC subclass F24H recorded 123,801 patent applications worldwide between 2013 and 2023. Annual filings grew from 7,646 in 2013 to 11,949 in 2023 (+56%), peaking at 14,672 applications in 2020. The most active applicants in class F24 are MIDEA (21,834 applications), GREE ELECTRIC APPLIANCES (21,535 applications) and GUANGDONG MIDEA REFRIGERATION EQUIPMENT COMPANY (20,870 applications).
Source: EPO PATSTAT, worldwide filings
In class comparison
F24H ranks 2nd of 9 subclasses with filings in F24, with 123,801 applications between 2013 and 2023, 14.2% of the class. Annual filings grew 56% from 2013 to 2023, below the class as a whole (+83%).
| Rank | Subclass | Title | Applications | Share |
|---|---|---|---|---|
| 1 | F24F, Air-Conditioning; Air-Humidification; Ventilation; Use of Air Currents for Screening | Air-Conditioning; Air-Humidification; Ventilation; Use of Air Currents for Screening | 427,113 | 49.1% |
| 2 | F24H | Fluid Heaters, e.g. Water or Air Heaters, Having Heat-Generating Means, e.g. Heat Pumps, in General | 123,801 | 14.2% |
| 3 | F24C, Domestic Stoves or Ranges; Details of Domestic Stoves or Ranges, of General Application | Domestic Stoves or Ranges; Details of Domestic Stoves or Ranges, of General Application | 116,007 | 13.3% |
| 4 | F24D, Domestic- or Space-Heating Systems, e.g. Central Heating Systems; Domestic Hot-Water Supply Systems; Elements or Components Therefor | Domestic- or Space-Heating Systems, e.g. Central Heating Systems; Domestic Hot-Water Supply Systems; Elements or Components Therefor | 88,434 | 10.2% |
| 5 | F24S, Solar Heat Collectors; Solar Heat Systems | Solar Heat Collectors; Solar Heat Systems | 72,075 | 8.3% |
| 6 | F24J | 21,125 | 2.4% | |
| 7 | F24B, Domestic Stoves or Ranges for Solid Fuels; Implements for Use in Connection With Stoves or Ranges | Domestic Stoves or Ranges for Solid Fuels; Implements for Use in Connection With Stoves or Ranges | 12,566 | 1.4% |
| 8 | F24T, Geothermal Collectors; Geothermal Systems | Geothermal Collectors; Geothermal Systems | 6,275 | 0.7% |
| 9 | F24V, Collection, Production or Use of Heat Not Otherwise Provided for | Collection, Production or Use of Heat Not Otherwise Provided for | 2,265 | 0.3% |
Source: EPO PATSTAT, worldwide filings
Additional Content
Limiting references
Steam generation
Application references
Arrangement or adaptation of heating devices specially for passenger or goods spaces of vehicles, the heat being derived otherwise than from the propulsion plant Air-heating in railway vehicles Air-heating in ships or other waterborne vessels Arrangements or adaptations of air-treatment apparatus for aircraft crew or passengers, or freight space, the air being heated Domestic- or space-heating systems; Domestic hot-water supply systems
Related Keywords
8 direct subcodes
Child Classifications
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- F24H 1/00 Water heaters, e.g. boilers, continuous-flow heaters or water-storage heaters
- F24H 15/00 Control of fluid heaters
- F24H 3/00 Air heaters
- F24H 4/00 Fluid heaters characterised by the use of heat pumps
- F24H 6/00 Combined water and air heaters
- F24H 7/00 Storage heaters, i.e. heaters in which the energy is stored as heat in masses for subsequent release
- F24H 8/00 Fluid heaters characterised by means for extracting latent heat from flue gases by means of condensation
- F24H 9/00 Details
Top Applicants
Top 10 applicants by patent filingsfor class F24, 2013–2023, worldwide · Source: EPO PATSTAT
- MIDEA 21,834
- GREE ELECTRIC APPLIANCES 21,535
- GUANGDONG MIDEA REFRIGERATION EQUIPMENT COMPANY 20,870
- QINGDAO HAIER AIR CONDITIONER COMPANY 15,443
- HAIER SMART HOME 15,442
- QINGDAO HAIER AIR CONDITIONER ELECTRIC COMPANY 10,008
- AUX AIR CONDITIONING COMPANY 7,723
- NINGBO AUX ELECTRIC COMPANY 7,499
- NINGBO FOTILE KITCHENWARE COMPANY 6,712
- LG ELECTRONICS KR 6,441