Ductless mini split is not keeping room up to temperature. Only getting a 13° temperature differential between supply and return. There is not enough air movement going across coil due to blower wheel being extremely dirty and is throwing wheel off balance as well. Need to do a thorough cleaning on indoor head and recommended installing a UV light strip in inside mini split to prevent biological group from continuing to grow. After system is clean can check pressures properly to see if there is the right refrigerant level in system.