Black Water Tank Issue

I would replace the drain valve. No telling what the drain cleaner did.
The tank its self should be ok.

Next time the tank won't drain.
Connect the drain hose, lift the open end higher than the tank.
Fill hose with water.
Open the drain valve. The water in the hose will push the clog back.
Close the drain valve.
Carefully connect the hose to the sewer drain and empty.

Kiz wrote:
This neophyte needs help from those more experienced, and I apologize for the novel. My unit is a park model stationery RV. At the end of last season, my black tank plugged on a Friday evening when all RV places were closed, so I went on the advice of the local hardware store who sold me a drain cleaner, supposedly safe for setptic fields, and they assured me would not harm my system. Long story short, the toilet 'melted', and the black tank is not holding water. When I fill it up, it drains within about 10 minutes. There is no water in the underbelly. I had the toilet replaced when the unit was winterized, and they told me it should fix the black tank issue as well. However, I am thinking that I likely melted the black tank valve as well, and should probably have this replaced before using.... what are the thoughts of those more experienced?

I'm not familiar with park models but I was under the impression they were connected to the sanitary drain without a black or gray tanks.

Home’s suggestion will work but be careful.

To Stickdog - this is like a hybrid unit... park model travel trailer that can be towed, but is located on a permanent site - sadly, it still has holding tanks.

To Home Skillet - thanks for your input. I would have done that, except the tank was full, and as others had been using it before me, I wasn't sure quite how full. Hopefully there won't be a next time, fingers crossed.

stickdog wrote:

Kiz wrote:
This neophyte needs help from those more experienced, and I apologize for the novel. My unit is a park model stationery RV. At the end of last season, my black tank plugged on a Friday evening when all RV places were closed, so I went on the advice of the local hardware store who sold me a drain cleaner, supposedly safe for setptic fields, and they assured me would not harm my system. Long story short, the toilet 'melted', and the black tank is not holding water. When I fill it up, it drains within about 10 minutes. There is no water in the underbelly. I had the toilet replaced when the unit was winterized, and they told me it should fix the black tank issue as well. However, I am thinking that I likely melted the black tank valve as well, and should probably have this replaced before using.... what are the thoughts of those more experienced?

I'm not familiar with park models but I was under the impression they were connected to the sanitary drain without a black or gray tanks.

Bingo TRUE PARK models have no holding tanks. AND, they usually have residential type toilets but not always. Since he has NO water coming out anywhere, that shows he has no tank and his system is functioning as designed. AS to using Draino and such, about 35 years ago I had a customer bring his Motorhome in for toilet draining problems. I had to pull the toilet. As I lefted the toilet and carries it out of the motorhome liquid splashed all over the carpet and on my work jeans. Once outside my legs started to burn. I looked down and my jeans were dissolving. I quickly pulled off my jeans and washed my legs down luckily no harm to my legs. I walked back inside his Motorhome and his carpet was dissolved every place the liquid hit. I called the customer and he had no idea what was in the toilet. Then he called the next day and admitted he rents out the motorhome and the previous renter poured the drain cleaner in the toilet. Customer had an expensive lesson in renting and not what to do with an RV toilet. Doug

PS, 15 years ago after Hurricane Katrina, we had a lot of potential customers call us to add Fresh/Gray/Black tanks to the very used FEMA Park Model trailers FEMA supplied to the victims. They bought the trailers for what they thought was a great price and then found out they were NOT self Contained RV trailer models.

So if you have are sure you have a black tank. And if that tank is not holding water but rather letting the liquids drain out. Then yes you need to get that issue (probably the valve) fixed as soon as possible. Right now the liquid is draining out of the tank and the solids are staying behind and piling up on the floor of the tank. If this is not addressed you will soon have the dreaded pile of poop under the toilet and another plug to clean out.

The valve itself might still be functioning and the seals are melted. But with the possibility of melting damage on the valve itself I would probably just spend the extra $10 to replace the entire valve.

Valterra valve
Camco valve

stickdog wrote:

I'm not familiar with park models but I was under the impression they were connected to the sanitary drain without a black or gray tanks.

I'll second that comment.. Did not know a park model had waste tanks.

Oh well. Live and learn.

I would not use Any Drain cleaner product in the type of tank they have on RV's. that plastic can (and will as you found out) Melt.

Side story; Also true true (yes it's a twice told tale)

Years ago when I was working out of a State Police post as a dispatcher there was a tank truck spraying contents that turned the grass brown. Well I called the shipper and it turns out it was a concentrated industrial cleaner.. C, Calcium Chloride or one of the bleach products (Forget which) and 50% water.
(I've been retired almost 18 years after all)

Well the rest of the story I heard about 15 years later after we had gone to central dispatch from teh Motor Carrier Haz-Mat officer who investigated.... both times.

When the company got an order for 10,000 gallons they called the trucking company and the dispatcher said "Stainless Steel or Aluminum"
The CEO (Whom I spoke with, more on that later) Ask his Chief Chemist (She's got to be sleeping with him. I mean same Chemist both times)
she ask "what's the difference" Dispatcher said either Aluminum is cheaper or Stainless is more expensive so they went with Aluminum.

NOW.. In the store you can buy a common produce .. It is Potassium Hydroxide crystals and aluminum shavings and the can warns to keep it dry till use.

DRAINO yup DRAINO and You know what happens when DRAINO gets wet

Well I saw photos of the truck the 2nd time.. WOW Not much left of the tank after the lye ate it

Oh When I called the CEO tried to dazzle me with his brillance (I have a degree in science) I translated Potassium Hydroxide to LYE and the Chlorine compound to Bleach and I will give him credit for dropping the BS. ... NEVER mess with a dispatcher.

Like I said about 15 years later.. Second verse, Same as the first, and she's still the chief chemist.
Only they can no longer rent tank trucks.

Home Skillet wrote:
I would replace the drain valve. No telling what the drain cleaner did.
The tank its self should be ok.

Next time the tank won't drain.
Connect the drain hose, lift the open end higher than the tank.
Fill hose with water.
Open the drain valve. The water in the hose will push the clog back.
Close the drain valve.
Carefully connect the hose to the sewer drain and empty.

And please have someone running the video while you do it!!!

opnspaces wrote:
So if you have are sure you have a black tank. And if that tank is not holding water but rather letting the liquids drain out. Then yes you need to get that issue (probably the valve) fixed as soon as possible. Right now the liquid is draining out of the tank and the solids are staying behind and piling up on the floor of the tank. If this is not addressed you will soon have the dreaded pile of poop under the toilet and another plug to clean out.

The valve itself might still be functioning and the seals are melted. But with the possibility of melting damage on the valve itself I would probably just spend the extra $10 to replace the entire valve.

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Thanks - Did not put any solids down at all once I discovered this - it's been emptied and rinsed, and not used over the winter, so no buildup at this point. It's a bit of a journey for me to get there, especially with travel restrictions, and no public washrooms open in the resort where it's located. I want to try and set the techs up for when I can be there, but want to know what I might be dealing with in advance.

opnspaces wrote:
So if you have are sure you have a black tank. And if that tank is not holding water but rather letting the liquids drain out. Then yes you need to get that issue (probably the valve) fixed as soon as possible. Right now the liquid is draining out of the tank and the solids are staying behind and piling up on the floor of the tank. If this is not addressed you will soon have the dreaded pile of poop under the toilet and another plug to clean out.

The valve itself might still be functioning and the seals are melted. But with the possibility of melting damage on the valve itself I would probably just spend the extra $10 to replace the entire valve.

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It's like a hybrid, and is listed on the sales cert as 'park model travel trailer'. I have tried attaching an image, but not sure if it worked.