Hvac systems and methods with low pressure operation

A heating, ventilation, and air conditioning (HVAC) system, comprising:

• a working fluid circuit comprising a compressor, a suction conduit configured to direct a working fluid to the compressor, and a heat exchanger configured to place the working fluid in a heat exchange relationship with an air flow;
• a fan configured to force the air flow across the heat exchanger;
• a pressure switch configured to detect a first pressure of the working fluid along the suction conduit, wherein the pressure switch is configured to actuate in response to detection of the first pressure below a first threshold value;
• and
• a pressure sensor configured to detect a second pressure of the working fluid along the suction conduit,
• wherein the HVAC system is configured to adjust operation of the fan in response to detection of the second pressure of the working fluid below a second threshold value, and the second threshold value is greater than the first threshold value.

A heating, ventilation, and air conditioning (HVAC) system, comprising:

• a compressor configured to circulate a working fluid along a working fluid circuit;
• a suction conduit of the working fluid circuit configured to direct the working fluid to the compressor;
• a heat exchanger of the working fluid circuit configured to place the working fluid in a heat exchange relationship with an air flow;
• a fan configured to force the air flow across the heat exchanger;
• a first pressure switch configured to detect a first pressure of the working fluid along the suction conduit, wherein the first pressure switch is configured to interrupt supply of power to the compressor in response to detection of the first pressure below a first threshold value;
• and
• a second pressure switch configured to detect a second pressure of the working fluid along the suction conduit, wherein the second pressure switch is configured to interrupt supply of power to the fan in response to detection of the second pressure below a second threshold value, and wherein the second threshold value is greater than the first threshold value.