Hi, I have an EUS Mark Heat Pump Pool Heater. When I turn on my heat pump, I get an LP code on the display. According to the manual, this means Low Pressure and can be a result of low refrigerant. I have noticed that there is an oily liquid around the heat pump. When I look inside there is about an inch of this same liquid inside. Could this be refrigerant? Could there be a leak? I have had my pool opened and closed in the past by a local pool company. Low funds make it impossible to do that this year. I need to be able to repair this problem myself. I am fairly handy, so I am sure I can do it if I can get some help here. Anybody have any ideas of what this might be and what I might do to check to see what it is?