Community Forums

gator67 · 06-19-2013, 04:27 PM

My gray tank sensor worked fine until recently. I never did understand how it worked, as you could adjust the setting if you chose to. When it was empty, I set it so the 2nd light would just come on so when the 5th light came on, I knew it was time to dump.

Now, the reading stays where I set it and doesn't move. How do the sensors work in the gray tank, and, what could be causing the failure?

I saw some posts about replacing some module but wasn't clear about wiring, etc.

Any thoughts?

cc8375 · 06-19-2013, 06:51 PM

Might want to be sure the probes / sensors are not dirty. Look at solutions from this link on previous threads

http://www.irv2.com/forums/f54/clean...ors-88157.html

http://www.irv2.com/forums/f50/clean...rs-131246.html

CC

gator67 · 06-19-2013, 08:31 PM

The problem is with the gray tank... not the black tank. And... it seems that most problems involve sensors being dirty and indicating that the level is higher than it really is. Mine appears to not register as the level gets higher in the tank.

Also, I'm not clear how the sensor works on mine. It's looks to me like there are not fixed sensors in the tank because the monitoring can be changed at the gauge on the panel. For example, I can adjust the indicator on the gauge so it shows half full when it is actually empty, if I choose.

Jim A · 06-19-2013, 08:55 PM

Unlike many other brands, on my '04 and I would assume your '05, there are no sensor probes inside the tanks to get contaminated. Cleaning the tank is not likely to fix your problem. There is a strip glued to the outside of the tank that measures capacitance changes depending on the fill level. I assume you are adjusting the reference capacitance when you "calibrate" the gauge. I would bet that the sensor has come loose. One of mine (the black tank) had come loose, with more than half of the sensor not in contact with the tank. If you take the access cover off in the maintenance compartment, you will see the sensors on the side of the tank.

I replaced mine a number of years ago with the SeeLevel gauge. Much improved reliability and more resolution, with increases measuring in 3 and 4% incriments from 0 to 100%. Worth every penny. It also works by attaching a sensor to the outside of the tank and measuring capacitance changes. Not all that difficult to install.

gator67 · 06-20-2013, 11:48 AM

Quote:

Originally Posted by Jim A

I replaced mine a number of years ago with the SeeLevel gauge.

Which model did you buy? Sure are lots of choices!

Jim A · 06-20-2013, 01:41 PM

I bought the 709-PH model. It measures the fresh, gray, and black tank levels, plus the LPG and a digital voltmeter. It has a switch for the water pump and the hot water heater. I never used the hot water heater switch, as the existing one is on the other side of the coach.

SeeLeveL Gauges by Garnet Instruments Ltd. - Model 709-PH

The links on the web page will allow you to look at the installation and shop manuals for the unit. They explain how it works.

IIRC you need to specify that you need a 3-way switch for the water pump unless you have installed a water pump relay, which I never did.

The 709 panel is smaller than the existing panel. I cut a 1/4" thick wood panel the size of the existing tank gauge to cover the hole and then cut a hole in it to accommodate the 709 panel.

My gray water tank is L shaped and was taller than the 12" limit for one sensor. I bought a second one to combine the two as described in the manual. If I was doing it again I could consider just using one 12" sensor, and know I had a little safety margin when the tank says it is full. The 12" sensors are fine for the black tank and the fresh water tanks.