RV Black Tank Flush System: Things you need to Know

Camping is no doubt a very exciting and interesting task for those who love traveling. Your camping experience becomes more exciting and beautiful when you travel in your RV. Having your RV is a blessing for traveling enthusiasts. However, the duties and responsibilities that come with your RV are another sides of the story.

The most difficult part of an RV traveling is the dumping and cleaning of the black tank. A black tank is a holding tank that is attached to the RV. It is used to hold the waste from the toilet. The proper drainage and flushing of the black tank are important to keep it clean.

A flush system of an RV makes sure that your RV’s black tank remains clean and free of any residue or debris.

RV Black Tank

An RV black tank is a holding container tank that is placed under your RV. There are mostly two tanks in an RV. One is called the black tank and the other is known as the grey tank. A Grey tank is used to hold water from showers and sinks etc in your RV. A black tank is used to hold all waste coming from the toilet of your RV. 

Black tanks come in many different sizes. The size ranges from 15 to 50 gallons. It is very important that you clean your RV black tank on a regular basis otherwise residue will start building up inside the walls of the black tank and it will become very difficult to clean it afterward. That is why a flush system is built in an RV to help in the cleaning process.

Flush System of an RV Black Tank

The flush system of an RV is the one that works with the dumping process of your RV’s black tank. The dumping process of an RV black tank includes dumping all contents of your black tank on a dumping station.

A black tank flush system is a system that is used to rinse out and clean the inside of your black tank. There are two types of black tank flush systems.

1- One is the permanent system installed with a water supply inlet. A garden hose and spray nozzles are connected to the water supply inlet. The nozzles and garden hose spray water onto the inside walls of your RV black tank to wash away and flush out any residue of human waste on the walls. The main purpose of this flush system is to flush away all the waste inside the tank or on the walls.

2- Another type is the portable RV tank flush kit. It is connected with your primary sewer connection where the sewer hose is connected during the dumping process. It also comes in the shape of a wand which you hold with your hands and insert inside your toilet to clean the black tank under your RV toilet. A garden hose is attached with the portable flush system for fresh water supply inside the black tank.

One thing is common in both the portable and fixed flush systems of an RV black tank. In both types, you have to attach a garden hose for freshwater supply. One or more spray nozzles are also attached to the garden hose to spray water inside the tank to properly clean it from any residue waste content.

Working on RV Black Tank Flush System

A flush system of an RV black tank works with the help of a garden hose and spray nozzles to spray fresh water inside the black tank and on the walls to clean and flush away any loose waste particles in the form of debris on the tank walls.

Some RVs have factory-fitted flush systems. However, in some RV models, you have to rely on manual flush systems. Whether it is a factory-fitted flush system or a manual one, you have to use a garden hose for the freshwater supply for cleaning the inside walls of the black tank.  

Some RV black tank systems have built-in anti-siphon valves installed. These valves serve as a backflow preventer. These valves are located above the flush inlet valve. The main purpose of an anti-siphon valve is to prevent the mixing of wastewater in the black tank with the freshwater system.

How Often Does an RV Black Tank Need Flushing?

An RV black tank does not need flushing every time you dump the black tank. This is a common concept that flushing an RV black tank helps in cleaning anything that is stuck to the walls of your RV black tank. Therefore if you feel that residue is building on the inside walls of your black tank, then you must flush the black tank.

Some RV black tanks come with a built-in flush kit. Therefore it becomes easy to flush the black tank every time you dump it. However, if your RV has to be flushed manually, then it is an effort-taking task and cannot be flushed every time you dump the black tank. However, flushing the black tank regularly prevents the toilet papers from causing the RV holding tank sensors to be misread.

Methods to Flush an RV Black Tank

Flushing an RV black tank is not a difficult method. It involves a few steps which are given below.

  1. First, connect the sewer hose of your RV, and then open the black tank valve. Now dump the waste from your black tank at the dump station.
  2. Now connect the water hose to the flush inlet in the black tank or to the flush device.
  3. Turn on the water and let the freshwater run inside the black tank for one or two minutes.
  4. While running the water, be careful that you do not overfill the black tank. That is why it is recommended to always open the black tank valve while flushing to prevent overfilling of the black tank.
  5. Let the water run till all the drain water runs clear.
  6. Turn off the water supply and let all the water drain.
  7. Close the black tank valve.

FAQ’s  

How Long will the Black Tank be flushed?

The black tank should be flushed until you see clear water draining out from the RV’s sewer outlet. Mostly the RV black tank flushing takes only a few minutes.