The unit i worked on has 2 compressors in the indoor unit and hum and i think a hot gas bypass to heat a little and a remote condenser on the roof. i was having a hum problem where the hum was low it was at 23% when it was needing to be at 30% i talk with tech support and said the float was not i right. I just don't think that was the problem and the M# S# i got off my CO computer in the office had 2 different units in there
I think you have ir bulbs and a pan. Just a few things to check out, these humidifiers are simple and they work awesome. Set point deadband, the bulbs, the limit switch on the bottom of the pan and the float if it trips the drain is plugged.