Community Forums

Dajoet · 07-13-2022, 02:04 PM

In my Coach the Shower and Bath Sink drain to the Gray Tank. A couple of times we found out the tank was full because the shower would not drain. The Macerator Toilet and Kitchen Sink drain to the Black Tank. Both tanks have the internal unreliable level probes and the Black Tank has mid and high external probes (more reliable) for the Toilet. While cleaning out the Black Tank the other day I found out that if you overfill it using the Kitchen Sink (toilet will not flush if top probe is on) the tank will overflow down the sides of the tank to the ground. I cannot see where the sink drain enters the tank, so I don't know if it overflowed from there or if there is an overflow on top of the tank.?? We have lived in the Coach for over one of the past five years and never had a problem with an odor. Also never used any tank additive. Just wondering what if anything I should do.

twogypsies · 07-13-2022, 03:57 PM

Hmmm... I wouldn't want the kitchen sink to drain into the black tank. I'd fear it would back up into the kitchen sink. Sorry I can't help.

Country Road · 07-13-2022, 06:55 PM

Quote:

Originally Posted by Dajoet

In my Coach the Shower and Bath Sink drain to the Gray Tank. A couple of times we found out the tank was full because the shower would not drain. The Macerator Toilet and Kitchen Sink drain to the Black Tank. Both tanks have the internal unreliable level probes and the Black Tank has mid and high external probes (more reliable) for the Toilet. While cleaning out the Black Tank the other day I found out that if you overfill it using the Kitchen Sink (toilet will not flush if top probe is on) the tank will overflow down the sides of the tank to the ground. I cannot see where the sink drain enters the tank, so I don't know if it overflowed from there or if there is an overflow on top of the tank.?? We have lived in the Coach for over one of the past five years and never had a problem with an odor. Also never used any tank additive. Just wondering what if anything I should do.

Are you sure it’s hooked up that way? Like twogypsies said, that is odd. Did you verify that, or is that what you think? If you haven’t verified, I’d drain everything and open faucets to verify.

Ray,IN · 07-13-2022, 06:59 PM

I see you have a 2006 Dynamax Grand Sport.

A holding tank overflowing only when full is likely an unsealed vent pipe. They exit the top of the tank and vent atop the roof.
Test where the any sink drains into with food coloring mixed in a sink of water. Have holding tanks empty and only one drain valve left open. Drain out the colored water while another observes the result outside.

shootist · 07-13-2022, 09:06 PM

Newer rvs have the kitchen and commode on black water. It balances the tanks better as far as usage and it allows you to dump grey water on lawns and what not where legal. By a see level 2 tank gauge setup and never worry again. Mine has blue tooth and it is great, tanks, voltage and propane. The propane does work off the original sender but your three tanks will have a stick on sender. No more bad sending units. I've heard now people are buying the longer ones and angleing them instead of being a little short on the tank depth. You'll understand when you check them out. Garnet is the company that makes them.

twogypsies · 07-13-2022, 10:22 PM

Quote:

Originally Posted by shootist

Newer rvs have the kitchen and commode on black water. It balances the tanks better as far as usage and it allows you to dump grey water on lawns and what not where legal.

If grey water goes into black tank how does that allow you to dump on lawns. You'd be dumping the black water, also.

Mudfrog · 07-14-2022, 08:08 AM

Quote:

Originally Posted by shootist

Newer rvs have the kitchen and commode on black water. It balances the tanks better as far as usage and it allows you to dump grey water on lawns and what not where legal. By a see level 2 tank gauge setup and never worry again. Mine has blue tooth and it is great, tanks, voltage and propane. The propane does work off the original sender but your three tanks will have a stick on sender. No more bad sending units. I've heard now people are buying the longer ones and angleing them instead of being a little short on the tank depth. You'll understand when you check them out. Garnet is the company that makes them.

Quote:

Originally Posted by twogypsies

If grey water goes into black tank how does that allow you to dump on lawns. You'd be dumping the black water, also.

I believe Shootist is saying that because the toilet and kitchen sink go into the black, that the gray consist of only shower and bathroom sink discharge which is ok to dump when allowed. Plumbed like that, there would be no poop or strong soap/grease/food particles in the gray.

But I'm not sure of the bolded. The wording makes it sound like "all" newer RV are plumbed that way. Sounds ok, but is that true?

As far as the OP's concern, I would not think there was overflow at tank level. Sounds like piping, maybe vent, may have come loose. But as mentioned, you'd think there would be some smell if this were the case.

shootist · 07-14-2022, 07:32 PM

Quote:

Originally Posted by twogypsies

If grey water goes into black tank how does that allow you to dump on lawns. You'd be dumping the black water, also.

No , grey water goes in grey water. Kitchen sink is considered blackwater because of the pathogens in it. And I don't know how many of the newer RVs are built that way. Just than many of them are.

Jkjavelin · 07-15-2022, 10:03 AM

So, you wash dishes in a sink that the black water can back up into?? C'mon!

saddlesore · 07-15-2022, 10:29 AM

Quote:

Originally Posted by Jkjavelin

So, you wash dishes in a sink that the black water can back up into?? C'mon!

I concur on the WTF.... I know that for the last 10/12 years [or longer].. Some Class A's only have a large fresh tank and a single combination Black/Gray tank. I suspect that there is a "P" trap and an anti back flow valve on the gray plumbing circuit.

96 Wideglide · 07-15-2022, 11:45 AM

Quote:

Originally Posted by shootist

Newer rvs have the kitchen and commode on black water. It balances the tanks better as far as usage and it allows you to dump grey water on lawns and what not where legal.

Well, if that's what they are doing, hopefully they are installing black tanks equal to the size of the grey tank, if not larger!

shootist · 07-15-2022, 01:04 PM

Some of you need to read state laws on what constitutes grey water. And if you back your black tank all the way to your kitchen sink you're already wading in it in the bathroom. If your black tank fills before your grey , you must be showering somewhere else or hardly at all. As well as the washing machine going through 11 gallons a load.