Grey water tanks...

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SeaGal

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There are two in our 2008 Cedar Creek 34SATS 5th wheel. There is only one exterior grey tank dump valve that I can find. Should there be two?
After dumping, just now, grey tank 1 shows 1/3 full and grey tank 2 still shows 2/3 full. Owners manual schematic shows one grey tank with the note that 'there may be two'. No further info. Help, please!
 

Rene T

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Yes you should have another handle. Look between the wheels. On the drivers side. That’s where mine is.
Also look down the frame for a hole where there may have been a rod going through the frame to the valve.
The only other option if that fails it pull down the belly, locate the gray tanks and their drain valves.
 

SeaGal

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Thank you for your reply. A cursory exam didn't find the other valve but its difficult for me to get under there for a really good look. When my son gets home I'll ask him to check, thank you.

I did find a small diameter short blue hose near the wheels with a valve on the end but it just drains on the ground when the valve is opened.
 

msw3113

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I did find a small diameter short blue hose near the wheels with a valve on the end but it just drains on the ground when the valve is opened.
That valve is likely your low-point cold water drain or a drain for your freshwater tank. It has nothing to do with grey water tank valve(s).
 

Rene T

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I looked and couldn't see one there. I'm beginning to wonder if both tanks are connected and there is just one drain.
I’ve never seen two tanks connected. Usually one tank is for your galley (kitchen sink) and the other tank is for your bathroom sink and shower. Like I said usually.
Don’t go by the tank level sensors. They are not accurate at all. The sensors get built up with scum and that gives false readings. The only one that usually works for me is the fresh water tank.
 

SeaGal

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I’ve never seen two tanks connected. Usually one tank is for your galley (kitchen sink) and the other tank is for your bathroom sink and shower. Like I said usually.
Don’t go by the tank level sensors. They are not accurate at all. The sensors get built up with scum and that gives false readings. The only one that usually works for me is the fresh water tank.
The one and only grey water valve I've found is marked 'galley tank' just above it. So the one I can't find must be for the shower and washer. Haven't used either one yet but the sensor on that reads 2/3 full - it has been reading E until recently. But I get what you say about the sensors. We do use the bathroom sink.
 
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Edd505

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I have two gray tanks and the main gray & black are side by side, the galley tanks at the rear with a separate handle. There was two separate" dumps, PITA, I tied them to a single out with two shut off valves. Chance one handles broken off and needs replaced? Gray Tank Mod
 

SeaGal

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I have two gray tanks and the main gray & black are side by side, the galley tanks at the rear with a separate handle. There was two separate" dumps, PITA, I tied them to a single out with two shut off valves. Chance one handles broken off and needs replaced? Gray Tank Mod
After reading your post I checked again. Next to the black water dump valve is a neatly patched area, looks like a black tarry substance about 6" by 3" in size. I'm wondering if the original owner did something similar. None of the piping shows like it does in your modification because there's a covering over the entire underneath. The main concern I have is that the sensor for Grey Tank 1 still shows 2/3 full when, until recently, it was reading empty. I'm afraid to use the washer. Is there any good reason that I shouldn't leave the galley tank drain valve open in case they are connected? (not the black water) We're full time, set up on our son's property, hooked into his septic.
 

Rene T

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We always leave the gray water tank valve open while camping. A couple of days before I need to dump the black tank I shut the gray tank valve to let the gray tank fill. Then I use that water to flush out the hose after dumping black tank.
I would be very careful about overfilling that gray tank that indicates 2/3 full. If you overfill it, you could rupture the tank.
The only sure way to find out what’s going on here is to open up the belly.
 

donn

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You did not mention age? But on my 34CKTS everything drained from one 4 inch outlet. The black and bath gray dump valves were lumped side by side very near the dump port. The kitchen gray dump valve handle was right near the street side front wheel. I suspect yoir will be in the same places. The kitchen gray dump valve is nearly impossible to activate if you have the slides open BTW.
 

Gary RV_Wizard

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I’ve never seen two tanks connected. Usually one tank is for your galley (kitchen sink) and the other tank is for your bathroom sink and shower.
I have, but there was still a valve between the tanks, so that you could allow or prevent the galley tank from draining. The galley tank didn't actually draininto the bath tank - it Teed to the bath tank outlet just ahead of the bath tank dump valve. That's actually a quite reasonable design that avoids the need for an external Y sewer hose. If you have sewer, leave both valves open and they both drain thru a single sewer hose. If not, both closed. When dumping, first open the bath tank valve. After it empties, pull the connecting valve so the galley drains as well. Then close both valves until the next time.
 

SeaGal

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You did not mention age? But on my 34CKTS everything drained from one 4 inch outlet. The black and bath gray dump valves were lumped side by side very near the dump port. The kitchen gray dump valve handle was right near the street side front wheel. I suspect yoir will be in the same places. The kitchen gray dump valve is nearly impossible to activate if you have the slides open BTW.
2008. I found grey tank 1 near the very front of the unit. I can see the drain lines going in - one for the bath and one for the washer (I think). I cannot see the drain line coming out. If the valve for that tank was next to the black water dump valve it is now missing, and there's a space that looks like it might have been for another valve but tarred over. The galley tank valve is in front of the front wheel as you said.
 

SeaGal

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I have, but there was still a valve between the tanks, so that you could allow or prevent the galley tank from draining. The galley tank didn't actually draininto the bath tank - it Teed to the bath tank outlet just ahead of the bath tank dump valve. That's actually a quite reasonable design that avoids the need for an external Y sewer hose. If you have sewer, leave both valves open and they both drain thru a single sewer hose. If not, both closed. When dumping, first open the bath tank valve. After it empties, pull the connecting valve so the galley drains as well. Then close both valves until the next time.
If you were going to connect the tanks where would a logical place be to put the connecting valve? Grey water tank 1 is very near the front of the unit and the galley tank is amidship. I've come to the conclusion that the valve for grey water one was purposely removed because there's what seems to be a repair job at the exact location where several folks said it should be - next to the black water dump. Or, the black water dump valve was removed and they're just using the 'gate valve' at the sewer line hookup as the black water dump valve. Either way, the one existing valve forward of the sewer outlet doesn't seem to release water from any tank...it's kind of floppy.
 

Gary RV_Wizard

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I'm afraid logic often has little to do with RV plumbing & layouts.Low cost and ease of factory installation are typically the priority considerations. And the techs in the design dept are endlessly creative!

The one old 5W I owned that had two tanks put the galley tank valve right next to the others, right where the Tee was plumbed. Another I look at closely had a valve near the forward tank and another near the rear galley, but that one had separate dump valves for each (you needed to use a Y hose to connect both or connect the sewer hose first to one, then move it to the other for dumping.
 

Edd505

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I'm afraid logic often has little to do with RV plumbing & layouts.Low cost and ease of factory installation are typically the priority considerations. And the techs in the design dept are endlessly creative!

The one old 5W I owned that had two tanks put the galley tank valve right next to the others, right where the Tee was plumbed. Another I look at closely had a valve near the forward tank and another near the rear galley, but that one had separate dump valves for each (you needed to use a Y hose to connect both or connect the sewer hose first to one, then move it to the other for dumping.
I left both my gray valves in so I'm able to dump one at a time in the single outlet. Y was a PITA and so was moving to get both tanks so I did the connection just below the belly wrap so valves are still inside the heated underbelly.
 
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