Heat pump system compressor start fault detector

A compressor fault detection and control system (hereinafter "fault detection system") for reverse cycle refrigeration system (hereinafter "system") for heating and cooling a building wherein said system comprises refrigerant compression means, refrigerant compression control means, an indoor coil, an outdoor coil, and refrigerant conduit means connecting said compression means and said coils, said fault detection system comprising:

• outdoor air temperature sensing means (hereinafter "TODAS") having an output indicative of outdoor air temperature (hereinafter "TODA");
• compressor discharge temperature sensing means (hereinafter "TDSCHS") having an output indicative of the temperature (hereinafter "TOSCH") of the refrigerant discharged from said refrigerant discharge means;
• and
• controller means having operative connections to said TODAS, TDSCHS, and to said refrigerant compression control means whereby said compression means is enabled to operate or is inhibited from operating, said controller means also including timing means and means for comparing an initial value of TDSCH (hereinafter "TD.sub.1 ") measured at or near the start of the compressor and the value of TDSCH (hereinafter "TD.sub.2 ") after a predetermined time interval after the measurement of TD.sub.1, said controller being characterized by being adapted to inhibit said compression means from operating if, after said preselected time interval as measured by said timing means, the value of TD.sub.2 is less than the value of TD.sub.1 plus a preselected constant, and post compressor start-up compressor shutdown means comprising said controller means including further means for comparing, on a substantially continuous basis, the values of TDSCH and TODA and for inhibiting the operation of said compression means if the value of TDSCH is less than the value of TODA plus a predetermined constant.

A compressor fault detection and control system (hereinafter "fault detection system") for a reverse cycle refrigeration system (hereinafter "system") for heating and cooling a building wherein said system comprises refrigerant compression means, refrigerant compression control means, an indoor coil, an outdoor coil, and refrigerant conduit means connecting said compression means and said coils, said fault detection system comprising:

• outdoor air temperature sensing means (hereinafter "TODAS") having an output indicative of outdoor air temperature (hereinafter "TODA");
• compressor discharge temperature sensing means (hereinafter "TDSCHS") having an output indicative of the temperature (hereinafter "TOSCH") of the refrigerant discharged from said refrigerant discharge means;
• and
• controller means having operative connections to said TODAS, TDSCHS, and to said refrigerant compression control means whereby said compression means is enabled to operate or is inhibited from operating, said controller means also including timing means and means for comparing an initial value of TDSCH (hereinafter "TD.sub.1 ") measured at or near the start of the compressor and the value of TDSCH (hereinafter "TD.sub.2 ") after a predetermined time interval after the measurement of TD.sub.1, said controller being characterized by being adapted to inhibit said compression means from operating if, after said preselected time interval as measured by said timing means, the value of TD.sub.2 is less than the value of TD.sub.1 plus a preselected constant, first post compressor start-up compressor shutdown means comprising said controller means including means to inhibit said compression means from operating, if, after a said preselected time interval as measured by said timing means, the value of TD.sub.2 is less that the value of TD.sub.1 plus a predetermined constant, and second post compressor start-up compressor shutdown means comprising said controller means including further means for comparing, on a substantially continuous basis, the values of TDSCH and TODA and for inhibiting the operation of said compression means if the value of TDSCH is less than the value of TODA plus a predetermined constant.