Sump Pump in basement not working

[rickracko]

Ok, I bought my house about 4 yrs ago and it was completely remodeled with an added completely furnished basement with full bathroom..I have 2 sump pumps which i know one seems to be a back-up but the other that takes most of the load seems not to be working, usually you could hear it working and now all i get is a humming noise from the machine, its a RIGID AQUA PRO RESIDENTIAL SEWAGE PUMP MODEL SEP-500, i have a toilet and a shower down there that i use regulary, washing machine isnt connected to this (thank god)....Is this thing DEAD and have to replace?? I removed 90% of the water in there to see if i could see anything wrong but i couldn't...Should i get someone to look at it or go out and buy a new one??? Thanks for any suggestions...