Fault detection diagnostic variable differential variable delay thermostat
US10712036B2 · kind B2 · utility
Inventors
Key dates
| Filing date | Feb 28, 2019 |
| Grant date | Jul 14, 2020 |
| Priority date | — |
| Expiry date | Feb 28, 2039 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B30/70
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A Fault Detection Diagnostic (FDD) variable differential and variable fan-off delay Heating Ventilating Air Conditioning (HVAC) thermostat control method. The FDD method detects a fan-on setting, reports a FDD fan-on alarm, overrides a fan-on setting, and turns off an HVAC fan. The FDD method detects, reports, and corrects a short-cycle by providing a variable differential based on: a cooling or heating cycle duration, or an off-cycle time. The variable fan-off delay is based on: a Conditioned Space Temperature (CST), comparing a current CST to the CST measured during the fan-off delay, a rate of change of CST with respect to time (dT/dt), dT/dt reaches an inflection point, the CST crosses a fan-off-delay differential, a cooling cycle duration, a heating cycle duration, a cooling temperature split, a heating temperature rise, an outdoor air temperature, a supply air temperature, or the rate of change with respect to time of these HVAC parameters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.