Scroll compressor differential pressure control during compressor startup transitions

A method comprising:

• controlling a condenser fan at a first speed according to a proportional integral derivative (PID) method;
• determining whether a scroll compressor in a tandem set of compressors in a cooling system has been activated;
• and
• overriding the PID method when the scroll compressor has started controlling the condenser fan at a second speed based on an outdoor ambient temperature, a predetermined temperature and a first predetermined speed for the condenser fan, wherein the second speed is less than the first speed and greater than zero.

A system comprising:

• a cooling module configured to determine a cooling value;
• a comparison module configured to compare the cooling value to an activation point of a lead compressor, wherein the lead compressor is in a tandem set of scroll compressors of a cooling system, and wherein the tandem set of compressors comprises a lag compressor;
• a lead compressor module configured to activate the lead compressor when the cooling value is greater than the activation point;
• a lag compressor module configured to activate the lag compressor subsequent to activating the lead compressor;
• and
• a control module configured to determine whether a plurality of conditions exist including
• (i) an alarm associated with the lag compressor is generated, and
• (ii) the lead compressor is deactivated,
• wherein the lag compressor module is configured to deactivate the lag compressor when at least one of the plurality of conditions exists in the cooling system.