Microprocessor control for a heat pump water heater
US6212894A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 28, 1997 |
| Grant date | Apr 10, 2001 |
| Priority date | — |
| Expiry date | Mar 28, 2017 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF25B49/02
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A microprocessor based control system monitors and controls a heat pump water heater system and interfaces the water heating system with an external centralized control system. The microprocessor control system includes sensors, safety switches, device interface relays, user interface devices and precanned software to provide versatile monitoring and control over a heat pump type water heating system. The system generally involves a typical heat pump coupled with a domestic water heater, hot water retention tank or other body of water. The control system provides operational control over the heat pump to maintain the hot water stored in the domestic water heater in a predetermined setpoint and controls the use of electric resistance heating elements in the domestic water heater for added heating capacity for quick heat recovery type operation. The control system receives a centralized signal typically from a utility company to disable heat pump water heating operation during peak demand time periods. Control logic is provided to carry out effective liming parameter control, high evaporator temperature control, and defrost/anti-freeze protection control.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.