- Burners, furnaces, boilers, and strokers (4)
- Boilers, low-pressure heating: steam or hot water (7)
- Gas-oil burners, combination (2)
- Stokers, mechanical: domestic or industrial (1)
- Room and wall heaters, including radiators (1)
- Logs, gas fireplace (3)
- Radiators, except electric (1)
- Solar heaters and collectors (7)
- Steam heating apparatus (1)
- Stoves, wood and coal burning (3)
