Please help! Last night I turned my thermidistat down from 75 to 73. The heat pump would only run a few minutes and the shut down. The fan and thermiistat said it was still running and calling for cooling. The compressor stays off for a few minutes and then starts up again. It did this all night and it took 7 hours to bring the temp down 2 degrees. The compressor must be kicking out on high or low pressure. I just had it serviced about 2 weeks ago. They cleaned it and checked the pressures etc. They added a bit of 410A. Any body any ideas?