Christopher H Sanders

US Patent:

20180031292, Feb 1, 2018

Filed:

Jul 26, 2016

Appl. No.:

15/220301

Inventors:

Mingsheng Liu - Omaha NE, US
Changlin Sun - Omaha NE, US
Christopher L. Sanders - Houston TX, US

International Classification:

F25B 49/02

Abstract:

A method of controlling a condenser fan of a heating, ventilating, and air-conditioning (HVAC) system based on a comparison of a refrigerant flow rate to maintain a valve position of an expansion valve. In the method, a controller modulates the condenser fan to maintain the valve position of the expansion valve at a valve position setpoint when the refrigerant flow rate is higher than the critical flow rate. The method also comprises controlling the speed of the condenser fan of the HVAC system to maintain a condensing measurement at a plurality of condensing measurement setpoints when the refrigerant flow rate is higher than the critical flow rate. The method also comprises controlling the speed of the condenser fan to maintain a condensing measurement at a plurality of condensing measurement setpoints when the condensing temperature measurement is higher than an ambient air temperature value plus at or around 5 F.