Preform maintenance on heat pump system with electrical back up heating and bypass humidifier: - open air handler cabinet door - chemically sprayed, brushed and rinsed indoor evaporator coil clean and clear - brushed primary pan and ez trap clean and clear - chemically treated primary pan and drain line - added condensate tablets - flushed and tested all drainage with hot water - secured and inspected electrical wiring and components - replaced 18x18x1 air filter - the customer has a humidifier with the wrong water panel installed - removed old water panel- washed and clean cartridge, installed #45 water panel and tested system operations- normal - call for heating and test heat pump operations - condenser is on and running - blew out and dusted electrical cabinet and components clean and clear - immediately found heavy traces of oil at condenser - connect gauges to equipment and found system low on R410 A - this is a Lennox condenser with leaks around the reversing valve The custome