F24D 12/02
Domestic- or space-heating systems: other central heating systems: having more than one
Official title: having more than one heat source (using heat pumps, in water central heating systems F24D3/18; in air central heating systems F24D5/12; in systems using heat storage masses F24D11/02)
F24D12/02 (Domestic- or space-heating systems: other central heating systems: having more than one) appears on 222 US grants and 239 published applications in this corpus.
Search patents in F24D- Granted patents
- 222
- Published applications
- 239
- Assignees
- 145
- Inventors
- 545
- Latest grant
- 21 Apr 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 1 | 0 |
| 1977 | 4 | 0 |
| 1978 | 6 | 0 |
| 1979 | 3 | 0 |
| 1980 | 1 | 0 |
| 1981 | 2 | 0 |
| 1982 | 8 | 0 |
| 1983 | 6 | 0 |
| 1984 | 6 | 0 |
| 1985 | 5 | 0 |
| 1986 | 2 | 0 |
| 1987 | 2 | 0 |
| 1988 | 0 | 0 |
| 1989 | 1 | 0 |
| 1990 | 2 | 0 |
| 1991 | 1 | 0 |
| 1992 | 2 | 0 |
| 1993 | 0 | 0 |
| 1994 | 1 | 0 |
| 1995 | 2 | 0 |
| 1996 | 0 | 0 |
| 1997 | 2 | 0 |
| 1998 | 2 | 0 |
| 1999 | 1 | 0 |
| 2000 | 2 | 0 |
| 2001 | 1 | 1 |
| 2002 | 5 | 2 |
| 2003 | 1 | 4 |
| 2004 | 5 | 5 |
| 2005 | 3 | 8 |
| 2006 | 2 | 1 |
| 2007 | 3 | 9 |
| 2008 | 3 | 9 |
| 2009 | 4 | 18 |
| 2010 | 8 | 20 |
| 2011 | 6 | 23 |
| 2012 | 8 | 13 |
| 2013 | 6 | 16 |
| 2014 | 5 | 11 |
| 2015 | 14 | 18 |
| 2016 | 14 | 10 |
| 2017 | 6 | 16 |
| 2018 | 16 | 11 |
| 2019 | 6 | 6 |
| 2020 | 8 | 6 |
| 2021 | 7 | 8 |
| 2022 | 6 | 5 |
| 2023 | 8 | 6 |
| 2024 | 5 | 2 |
| 2025 | 9 | 6 |
| 2026 | 1 | 5 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Multi-energy coupled cooling/heating system for buildings in long-term cooling region and operation method21 Apr 2026US 12,607,389 B2North China Municipal Engineering Design & Research Institute Co., Ltd.
- System and method for hydronic distribution with submersible pumps in an unpressurized tank30 Dec 2025US 12,510,255 B2Hunt Utilities Group LLC
- Dual source heat pump system9 Dec 2025US 12,492,841 B2Schlumberger Technology Corporation
- Flue gas energy recovery system and method25 Nov 2025US 12,480,720 B2Carbon Cap Inc.
- Flowrate determination system and method for a flow control valve14 Oct 2025US 12,442,556 B2Tyco Fire & Security GmbH
- Method and installation for providing energy, particularly thermal, low-carbon energy, in at least one building or the like, and related system20 Aug 2026US 2026/0246281 A1Accenta
- Hybrid heating system with humidity control4 Jun 2026US 2026/0153253 A1Midea Group Co., Ltd.
- Dual source heat pump system9 Apr 2026US 2026/0098657 A1Schlumberger Technology Corporation
- Three-pipe thermal network26 Feb 2026US 2026/0055901 A1ExerGo SA
- Systems and methods for hybrid heating system control26 Feb 2026US 2026/0055928 A1Honeywell International Inc.
Most cited
By later US patents
- Multi-phase modular comfort controlled heating system131US 4,337,893 AEnergy Savings Parhelion · 1982
- Integrated full processor, furnace, and fuel cell system for providing heat and electrical power to a building128US 5,985,474 APlug Power Inc. · 1999
- Method and apparatus for controlling a multi-source heating system85US 6,874,693 B2Honeywell International Inc. · 2005
- Utilities container82US 6,393,775 B12002
- Climate control system including responsive controllers74US 8,689,572 B2Emerson Electric Co. · 2014