Higher Than the Sun wrote:...When I'd initially turn the power on and press "clean" it would sound like something was whirring up (a soft sound), and then the sound would sort of tone down, and then stop - that's when Scooba would give the error beep and the "check tank" light would come on.
vic7767 is right about doing a liquid purging (search for "turkey baster") of Scooba's pump, since one reason Scooba lights the CheckTank warning is it "thinks" the Tank's Clean chamber is empty.
There is no sensor inside the Tank to tell Scooba's controller about the quantity of cleaning solution inside the Clean chamber. The sensor that does that job is hidden in the Solution Inlet fitting; this thing:
The sensor in that fitting may be dry because no solution is flowing from the Tank. Its a gravity flow system. The tip of the Solution Inlet presses on, and opens a valve inside the tank to allow solution to escape. Fluid may refuse to flow for at least two reasons: 1) valves in the pump are stuck shut (purging will overcome that condition), and 2) the tip of the Solution Inlet may have been damaged in a manner that shortened it, hence it can't open the tank-valve anymore!
So, those are some things to check.
I found that if you give Scooba a little push (very little push; you don't need to start rolling it forward) then it'll take off and go through a cycle on its own. ...
Pushing Scooba should have nothing to do with making it start a mission! OTOH, giving a a sharp rap, or bump, might indicate existence of an intermittent connection going to the pump-motor (that sort of thing used to be a popular fault).
This statement of yours concerns me:
...I'd initially turn the power on and press "clean" it would sound like something was whirring up (a soft sound), and then the sound would sort of tone down, and then stop ...
Normally: a) the pump (that whirring sound) starts before anything else and you hear that sound for three or four seconds, but the pump's sound is then drowned out by the louder noise of Scooba's blower-motor spinning up (the noisiest Scooba sub-system)! b) Scooba will start its initial spiral sweep and you should see a solution trail behind it. If liquid is not leaving the Clean chamber, it can't wet the sensor to tell the controller its OK to start the blower and wheels running, so you should check the above items.
To learn more about Scooba's pump, you can read about its innards on this page:http://mysite.verizon.net/gsplews/17PumpAsm.htm