A heating, ventilating, and/or air conditioning (HVAC) system includes a variable speed pump configured to direct a chilled fluid through a free cooling circuit of the HVAC system. The free cooling circuit is configured to place the chilled fluid in a heat exchange relationship with ambient air. The HVAC system also includes a heat exchanger configured to place the chilled fluid in a heat exchange relationship with a conditioning fluid and a controller configured to operate the variable speed pump based on a parameter of the HVAC system.