Shower wont drain unless black tank is dumped

Here is the routine I have developed over the snowbird winters.

1. Get a clear sight adapter and put it between the trailer and the sewer hose.
2. I leave the black tank closed for a week at a time. Grey tanks open.
3. I form a pee trap in the sewer hose with a couple boards, one 2x and a 4x4.
4. To dump and flush, I remove the pee trap boards.
5. Close the grey water tanks.
6. Open the black water tank and turn on the hose to the built in flush system.
7. Watch the sight tube until I am down to just hose water coming out.
8. Go inside and do two full bowl super flushes. "Bomb the Pile!" Note: Full bowl means filling the bowl to the bottom of the upper rim.
9. Go back outside and view discharge.
10. Close the black water tank and run the flush water in for four(4) minutes. Do not let anyone distract you at this point.
11. Open and drain and repeat 10 again.
12. Flush a bit and verify that you have nice clear water coming out of the tank. If not go back to step 8 and start again.
13. When you have nice clear discharge, put the pee trap boards back the sewer line and fill the pee trap.
14. Close the black water tank and add about a minute worth of water to the tank with the flush hose.
15. Secure the flush hose. I have a little inline valve adapter at the side of the trailer and the other end get turned off.
16. Open the grey water tanks and go add your chemical to the tank.

I have had the burping a couple of times, however the super flushes seem to have fixed that issue.

Having piles in not good!!

Chris

hardysgal wrote:
Hello, Boy could we use some help. We have a 2012 Keystone Montana. We made the mistake of leaving bland tank open. It clogged, we fould out the hard way. Before we had black pumped out by septic co, the shower clogged with 3 in water.
Black is finally unclogged, rinsed out best we can tell. We are able to use flushing toilet, no more problems, or so we thought.
Shower has standing water in it again. We dumped grey tank and it did not drain.
Dumped black and the shower drained(black not full but we tried everything)
This happens three more times. What could be causing shower to fill, needing black dumped......

Lift and remove the shower drain strainer. Take a metal clothes hanger, straighten a 12" length and make a hook on one end. Now reach down the shower drain and you will find soap scum and strings of hair. Remove all debris and clean the shower drain as far as you can reach. Take a plunger and push a few times and it will bring up other debris.

You had the black tank pumped out, but if you had a large mound of dried paper and poo only the liquid may have been removed so the usable volume may still be compromised which would require more frequent dumping. If you know the gallon capacity of your black tank and your gauge works I would empty the tank then close the valve and get a bucket of known volume and pour the number of gallons of water down the toilet till your gauge reads full. If that number is less than the capacity of your black tank I would assume you still have a pyramid of poo.

Lots of different plumbing set ups out there...
I have heard of units that plumbed the bathroom sink into the black tank. Possibly, but unlikely, the shower is plumbed into the black tank.

If not, the only way the shower could back up is if the trap is clogged or your gray tank is full.