Are My Tanks Really Empty?

[DallasSteve]

My gray water tank is filling up much faster in September. During the summer I could go 2 days between emptying the tanks. Now in September I have to empty the tanks every day. I just emptied the tanks and I looked at the meter on the wall. It says the black tank is 2/3 full and the gray tank is 1/3 full. Are those accurate? If they really are not empty why would that happen? My hose connection is made of clear plastic so I can watch the water come out. When I dumped the black tank a lot of brown water with some toilet paper flushed out. It seemed like about the normal amount to me. When I dumped the gray tank even more water rushed out under a lot of pressure for what seemed like a long time to me. I didn't time it, but my guess is about 10 seconds, then it slowed and emptied for another 5 or 10 seconds. Could there really still be another 1/3 or 1/2 a tank of gray water (and black water) in the holding tanks or is the problem that we are wasting more water and we need to reduce our water usage?

Edit: Last night, after only 12 hours since the last dump, the gray tank was so full there was an inch of water in the shower and the wall meter said it was full. Also, the motorhome is only 6 months old.

[DallasSteve]

Hurricaner wrote:

Winnebago has a lot of different models and maybe the Intent uses something different. I looked again at my black and gray tanks in the storage compartment and they each have about 4 wires connected to something that is screwed into the side of the plastic tank. I could take a photo, but it's not worth the time to me to upload it so I can link it here. If that is "non contact" then you are correct, but to me it looks like the sensors puncture the side of the tank to sense the water level.

No, you are correct. I just assumed Winnebago used the non contact on all their motorhomes but what you are describing is definitely the standard tank probes which are notorious for giving false readings. Still 30 seconds is pretty fast for a 42 gallon tank to drain unless you have a 3" drain valve vs a 1 1/2". Again if you are confident the tank is draining I would run off the pump which will give you a clue if something screwy is filling the tank.

Sam

The pump test sounds like a good idea. Sometime when we are not using much water I will give it a try and listen for the pump.

[Hurricaner]

Winnebago has a lot of different models and maybe the Intent uses something different. I looked again at my black and gray tanks in the storage compartment and they each have about 4 wires connected to something that is screwed into the side of the plastic tank. I could take a photo, but it's not worth the time to me to upload it so I can link it here. If that is "non contact" then you are correct, but to me it looks like the sensors puncture the side of the tank to sense the water level.

No, you are correct. I just assumed Winnebago used the non contact on all their motorhomes but what you are describing is definitely the standard tank probes which are notorious for giving false readings. Still 30 seconds is pretty fast for a 42 gallon tank to drain unless you have a 3" drain valve vs a 1 1/2". Again if you are confident the tank is draining I would run off the pump which will give you a clue if something screwy is filling the tank.

Sam

[DallasSteve]

Hurricaner wrote:
Winnebago has used what they call true level sensors for years unless something has changed in the last year. They are a non contact probe that mounts to the outside of the tank with glue. They are pretty darn reliable on the water and grey tank, the black can get toilet paper on the sides and fool them.
If you are confidant the tank is draining than something is filling it. The best way to determine that is to run off the water tank using the pump. You should be able to here the pump running when it shouldn't be and trace the problem from there.

Sam

Winnebago has a lot of different models and maybe the Intent uses something different. I looked again at my black and gray tanks in the storage compartment and they each have about 4 wires connected to something that is screwed into the side of the plastic tank. I could take a photo, but it's not worth the time to me to upload it so I can link it here. If that is "non contact" then you are correct, but to me it looks like the sensors puncture the side of the tank to sense the water level.

[Dusty_R]

Our first mh was a 1988 Mallard, it had tank probes and the monitor always worked.
Our next one was a 2001 Itasca, also with tank probes showing 1/3 levels. To me 1/4 levels would be a lot better. Anyway you could NOT depend the readings. My opinion the Mallard used the full 12 volts a-crossed the probes and the Itasca used a system like an Ome meter, and a film of moister would cause it to give faults readings.
A couple years after getting the '01 Itasca I learned about the SeeLevel system, got one and installed it. It gives readings in % which much better than thirds.
It has circuit boards that you peal and stick to your tanks. They use the original wires but only one.
We bought new 2014 Itasca in 2015, it also had a monitor panel that showed in thirds. I bought another new SeeLevel system and installed it in our new mh.

Dusty

[Hurricaner]

Winnebago has used what they call true level sensors for years unless something has changed in the last year. They are a non contact probe that mounts to the outside of the tank with glue. They are pretty darn reliable on the water and grey tank, the black can get toilet paper on the sides and fool them.
If you are confidant the tank is draining than something is filling it. The best way to determine that is to run off the water tank using the pump. You should be able to here the pump running when it shouldn't be and trace the problem from there.

Sam

[Katdaddy]

Sensors will get dirty and not read correctly. To clean, buy some liquid dishwasher detergent. When you leave home add 1 cup of the detergent and a couple gallons hot water to your tank. Dump when you get to campground. Depending on how dirty tanks are, you might have to do this a couple of times. I works great for gray and black tanks.

[DallasSteve]

Hurricaner wrote:
Winnebago uses non contact tank sensors and they're usually pretty accurate. You have a 42 gallon grey tank and it probably takes a lot longer than 20 seconds to empty, more like 2 or 3 minute's. Next time you dump look at the hose and make sure the tank has actually stopped draining. The other possibility that was mentioned earlier is some nut left one of the install cutouts in the tank and it is blocking the drain.

Sam

I can see the gray tank in my storage closet and it has wired sensors on the plastic sides, so those look like contact sensors to me.

I emptied my tanks again today and I timed them. The gray tank was full to the point of standing water in the kitchen sink. They took longer than my guess. The black tank water and solids rushed out for about 15 seconds and continued slower for about another 5 seconds. The gray tank water rushed out for about 30 seconds and continued slower for about another 5 to 10 seconds.

2 or 3 minutes is way more than it ever took to drain the gray tank, even when it was brand new. I still say the 30 seconds seems about the same as it was before when I drained after 2 days, instead of 1.

[Hurricaner]

Winnebago uses non contact tank sensors and they're usually pretty accurate. You have a 42 gallon grey tank and it probably takes a lot longer than 20 seconds to empty, more like 2 or 3 minute's. Next time you dump look at the hose and make sure the tank has actually stopped draining. The other possibility that was mentioned earlier is some nut left one of the install cutouts in the tank and it is blocking the drain.

Sam

[Sjm9911]

Fill up your fresh water tank, and run off of that with your pump. Dont run off your direct hose hook up, that will tell you a lot. Check the tanks after you use up your fresh water tank. And yea, most sensores are unreliable. I bought used, they never droled under 1/3 full in 2 years.

[NatParkJunkie]

you can check how you're leveled when dumping too. I have a truck camper, and the drain pipes come out the side of the waste tanks, not the bottom. I've found if the dump station isn't very level, if I am nose down, that the gray tank in particular will not drain all of the water out of the tank. I need to either turn around or pull up on leveling blocks to get the front end raised up so that all the water can actually drain out.

[DallasSteve]

Interesting ideas. I checked the manual and it says my gray tank is 42 gallons and the black tank 36 gallons. Are those reasonable amounts? I'd love to get 4-5 days and maybe I could do it alone but probably not with me and her. Even 2 days is liveable because when we travel we are usually only 1 or 2 days at a park. In that case I can dump when we leave. I'll see if I can get the wife to take shorter showers and I may look at buying paper plates and plastic cutlery. Thanks everybody.

[BFL13]

You can fill the grey tank till it overflows the shower drain (never mind the meter for this), then empty it into a 5 gal bucket as many times as it takes. Now you know how many gallons that was. Compare to spec size of grey tank in gallons.

If your actual holding is way less than spec gallons, now you know there is a blockage of some sort. If so, it could be a warranty issue on a new rig like that. Sometimes the facotry will have "stuff" left in the tank from shaving off plastic fittings or whatever.

Might be the air vent is blocked from not being up off the bottom of the tank

[Dusty_R]

You might look into the SeeLevel gauge system for your tanks, not all that hard to install and give read-out in % and I've them found accurate.

Dusty

[wopachop]

DallasSteve wrote:
or is the problem that we are wasting more water and we need to reduce our water usage?

Are you on pressurized city water? My first guess was you have a leak. But after thinking more what you describe is not all that crazy. You normally dump every 2 days, but now its everyday. That could be the difference of taking a 2 minute shower or a 7 minute shower.

Gonna take something pretty big to plug up the grey or black tank to the point it cant even drip slowly and empty completely.