Defrosting heat pumps
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
May 14, 1996
Grant Date -
N/A
app pub date -
Mar 30, 1994
filing date -
Mar 30, 1994
priority date (Note) -
In Force
status (Latency Note)
Importance
Abstract
Methods and apparatus for defrosting the outdoor coil in a variable speed heat pump system including determining, after the end of the last preceding defrosting, the optimal time to begin the next defrosting, and then initiating the defrosting responsive to the time interval since the end of the last defrosting tsD, the averages, over time, of liquid line temperature LLT, speed ES of the engine that drives the compressor, and outdoor dry bulb temperature ODT. The defrosting includes switching the system to the defrost mode at a predetermined maximum engine speed, periodically measuring the time taken during the defrosting ttD and the liquid line temperature LLT; periodically computing the rate of change of LLT with respect to time .DELTA.LLT/.DELTA.t, and when .DELTA.LLT/.DELTA.t is greater than the previous maximum value and ttD is greater than a predetermined time, storing the value of each in place of its preceding value. The defrosting ends when LLT becomes greater than a first predetermined temperature, or has been greater than a second predetermined temperature for at least a predetermined time; or a predetermined maximum time for defrosting MPDI has elapsed.
First Claim
Family
International Classification(s)
Cited Art Landscape
Patent Citation Ranking
Recipient Email Address
Recipient Email Address
Comment
Recipient Email Address
Add to Portfolio(s)
To add this patent to one, or more, of your portfolios, simply click the add button.
This Patent is in these Portfolios:
Add to additional portfolios:
Last Refreshed On:
Changes done successfully