US 6,981,384 B2
Monitoring refrigerant charge
Thomas J. Dobmeier, Phoenix, N.Y. (US); Michael F. Taras, Fayetteville, N.Y. (US); and Alexander Lifson, Manlius, N.Y. (US)
Assigned to Carrier Corporation, Syracuse, N.Y. (US)
Filed on Mar. 22, 2004, as Appl. No. 10/805,785.
Prior Publication US 2005/0204756 A1, Sep. 22, 2005
Int. Cl. F25B 45/00 (2006.01)
U.S. Cl. 62—149 20 Claims
OG exemplary drawing
 
1. A method of monitoring an amount of refrigerant in a refrigerant system having an electric motor driven compressor, a condenser and an evaporator;
determining a temperature difference between a saturation condensing temperature and a liquid refrigerant temperature of sub-cooled refrigerant; and
automatically determining a variance between the determined temperature difference and a desired temperature difference, and utilizing said variance to determine whether the amount of refrigerant in the refrigerant system is as desired.