Antifreeze system for instant water heaters
US6694093B2 · kind B2 · utility
4Cited by
6References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 25, 2002 |
| Grant date | Feb 17, 2004 |
| Priority date | — |
| Expiry date | May 25, 2022 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF24H15/37
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
An antifreeze heating system which prevents the freezing of water present in an instant water heater of the type having a primary heater which remains inactive under static flow conditions. A secondary heater is placed within an enclosed housing volume of the instant water heater, and electrically connected to a temperature-sensitive switch which activates the secondary heater when a monitored temperature, such as the ambient temperature, falls below a threshold value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.