Trane Problem
 

please any one can help I have trane pump with digital thermostat when I turn the heat on it works for 1 minute after that I hear the switch turned off and the fan running with no heat when I check the control board it is flashing and it is low pressure lock out I checked for the leak there is none what cause the his problem

Heat pump? What fan is running, the condenser fan or the indoor blower motor? Whats the outdoor ambient temp? What is the model # on this unit?