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Old 08-15-2019, 06:54 PM   #1
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2019 34RL2 Gray Tanks

Does anybody know how many gray tanks are in my 34RL2.Panel says there is a gray 1 and gray 2.There are 2 Gray handles in the basement.I am wanting to know what is plumbed to each of these,bath sinks, kitchen sink,shower etc.Tank sensors for those tanks are confusing me.Any ideas? Thanks for the help.
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Old 08-16-2019, 08:46 AM   #2
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Sinks in bath and washer together and shower and kitchen sink .
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Old 08-16-2019, 08:56 AM   #3
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put a plastic elbow on the sewer connection and close the valves. run some water (say 3 or 4 gallons) at a single faucet, ie kitchen sink. then go open one valve at a time to find out which tank / valve it ran into. drain tanks and repeat with every faucet / drain.
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Old 08-16-2019, 09:54 AM   #4
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I would test it as suggested above. Heard reference made that they can be different unit to unit.

Easy to test.
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Old 08-16-2019, 09:15 PM   #5
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We have 2 GREY water tanks as well and the one keeps filling up way too fast. Any ideas what’s going on here. Hardly even used the water the first day out and the tub started to fill up within a short while. Drained it and it filled up again after a short while.
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Old 08-17-2019, 07:00 AM   #6
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first, verify that you do really have two gray tanks. do you have two drain grey tank drain valves? there have been reports about generic control panels being used that indicate multiple tanks when there are only one.

next you need to do is verify what drains into each tank. spend the time to pour water into each drain and check which tank it drains into.

go look at the sewer hose connection. do you have only a single sewer hose connection for all tanks (black and two grays)? if so all the tanks must drain through this common connection. if this is the case you can buy a twist on external gate valve that twists onto the sewer hose outlet and the sewer hose connects to it. put one of these on and close its valve. then open the two gray valves. this will connect the two gray tanks and you will be able to use the combined capacity of both tanks. keep the black valve closed. to drain the tanks close the gray valves, open the twist off valve to drain what is in the lines. then proceed normally.
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Old 08-18-2019, 05:23 AM   #7
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Our 2019 34RL2 is exactly set up like Darylkalbach stated.
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Old 08-18-2019, 08:51 AM   #8
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What Darylkalbach stated is correct.

If you don't have a clothes washer installed, or not using one at the time, you can extend the galley/shower gray tank by interconnecting it with the vanity/washer tank. To do this, purchase a Valterra valve or similar to this one and attach to your sewer hose connect point:

By closing this add-on valve and opening both of your gray tank valves you can use essentially all of the 80 gallons of gray water capacity.

When ready to dump tanks first close the two gray tank valves. Connect hose and open the add-on valve which will drain gray water from the two gray water tank pipes. Then, dump black tank and flush, followed by dumping both gray tanks.

Hope this helps.
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Old 08-19-2019, 02:47 PM   #9
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So when we bought our 2019 37MBH I was under the impression that it only had 3 tanks - - 1 fresh, 1 black and 1 grey ---- but found that 1 we actually have 2 grey tanks. So after using different colored dyes, discovered the galley sink and the shower share one and the bathroom sink had it's own. Found that to be odd thinking how much water do you use in the bathroom sink for brushing teeth and such???? But ah.....this thread enlightened me that it would also be used for a washer.

Seeing that I don't have a washer nor do we have connections built in, how hard is it to add the connections now? Boy I wish we had one!
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Old 08-20-2019, 07:59 AM   #10
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On my 2017 34RL2 tank 1 is at the front of the trailer and it's for the washing machine and bathroom sink. Tank 2 is located behind tank 1 and it's for the shower and the kitchen sink. The black tank is located after tank 2 and the fresh water tank is last.
Hope this helps
Good luck
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Old 08-23-2019, 08:45 AM   #11
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2020 Silverback with same questions/issues

Thanks to all for clairifying this. Although we haven't used it yet, we have the washer/dryer setup. What we saw was one of the gray tanks kept filling up and the other stayed almost empty. Now that I know the two main sources of gray water for daily use, the shower and kitchen sink, are on one tank I can monitor our usage better.
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