Waste water gauges or sensors

[montiem]

I have looked in the owners manual to find an answer about holding tanks. The display for the amount in each tank, does it read in per cent age or gallons. This morning the grey tank was showing 69 and it was full, so the question % or gallons. We have a 60 gallon tank

[paz]

You don't say what kind of gauges you have, but the ones I know about all read in %. If that's the case, it sounds like your calibration is off. In your case, maybe you should interpret the reading as gallons.

[montiem]

I am not sure the brand of the gauges but the coach is a Newmar and that is the names on t he front. The owners manual gives instruction on how to calibrate the water tank but not the waste water tanks. I tend to think it is % but I really do not know. As I said in the first post the grey water was reading 69 and was full and would not drain shower

[gemini5362]

If they are the sensors that come with the coach those are inserted through the sides of the tank and are just switches. I do not believe there is any calibration to those. If you are lucky and you have see level gauges those can be calibrated. Since you do not know what kind of gauges they are go to the see level home page and download the manual then try to calibrate your gauges based on the procedure in the manual.