Method and apparatus for wiring room thermostat to two stage HVAC system
US6450409B1 · kind B1 · utility
66Cited by
5References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 15, 2000 |
| Grant date | Sep 17, 2002 |
| Priority date | — |
| Expiry date | Nov 15, 2020 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF24F2110/10
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A control used in a two stage HVAC system has a power supply from a 24 VAC transformer which is full wave rectified (D1, D2, D3, D4) to create DC voltages for a microcontroller (U1) and relays (K1-K3). All of the control information needed for the two stage control system is sent to the control from a room thermostat (12) having first and second stage cooling signal terminals (Y1, Y2) over a single line by connecting a diode between the Y1, Y2 terminals creating separate microprocessor recognizable signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.