My heat pump not running. HELP!?

the cheaper option is to replace pressure switch and add freon but thats only going to fix it temporarly you will have to spend more money later when you have to add more freon. remember the more freon you add the bigger the leak gets.. i recommend you get new coil and condenser and run strait cool and use your auxilary heat. that will be alot cheaper then going back to heat pump and the problem will be finalized.