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.

Not sure what size tanks you have but 10 seconds isn't long. I had an issue with a previous 5er where the tank cutout got pushed in front of the drain pipe and restricted outflow. That may be your situation here. For the black tank - do you let it get full before dumping? I wait until the toilet burps before dumping. That allows plenty of water volume to help flush stuff out. The sensors will rarely be accurate after the first few uses.

1. These gages are notoriously WRONG, when flow stops completely, the tank is empty, Black or grey, (unless you have a serious blockage.)2. It depends on tank outlet location, my outlet is at the rear corner of the tanks, so if you are setting nose down, you are probably not getting a complete dump.Do you have a leak, in a faucet, kitchen, bathroom sink, shower? other than that, I have no idea how you have a full grey tank in 12 hours, UNLESS your DW is dumping water and not telling you, is she taking LONG showers.I've never heard of tanks filling so quickly, we can usually go 5-7 days, but then we use a lot of paper products, so we generally do dishes once a day.

Tank gauges work sometimes and sometimes they don't, somewhat useless. Can't imagine filling a grey tank in 12 hours unless large family all taking showers.You may need to reinvent conservation here as the wife and I can go 4-5 days without dumping a tank.

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.

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

Are My Tanks Really Empty? | Good Sam Community

HappyKayakers
Explorer
Sep 29, 2020
Not sure what size tanks you have but 10 seconds isn't long. I had an issue with a previous 5er where the tank cutout got pushed in front of the drain pipe and restricted outflow. That may be your situation here.
For the black tank - do you let it get full before dumping? I wait until the toilet burps before dumping. That allows plenty of water volume to help flush stuff out. The sensors will rarely be accurate after the first few uses.
bukhrn
Explorer III
Sep 29, 2020
1. These gages are notoriously WRONG, when flow stops completely, the tank is empty, Black or grey, (unless you have a serious blockage.)
2. It depends on tank outlet location, my outlet is at the rear corner of the tanks, so if you are setting nose down, you are probably not getting a complete dump.
Do you have a leak, in a faucet, kitchen, bathroom sink, shower? other than that, I have no idea how you have a full grey tank in 12 hours, UNLESS your DW is dumping water and not telling you, is she taking LONG showers.
I've never heard of tanks filling so quickly, we can usually go 5-7 days, but then we use a lot of paper products, so we generally do dishes once a day.
kellem
Explorer
Sep 29, 2020
Tank gauges work sometimes and sometimes they don't, somewhat useless.

Can't imagine filling a grey tank in 12 hours unless large family all taking showers.

You may need to reinvent conservation here as the wife and I can go 4-5 days without dumping a tank.
wopachop
Explorer
Sep 30, 2020
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.
Dusty_R
Explorer
Sep 30, 2020
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
BFL13
Explorer II
Sep 30, 2020
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
DallasSteve
Nomad
Sep 30, 2020
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.
NatParkJunkie
Explorer III
Sep 30, 2020
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.
Sjm9911
Explorer
Sep 30, 2020
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.
Hurricaner
Explorer
Sep 30, 2020
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

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