HOW TO CLEAN BLACK WATER TANK IN RV

Most RVs have two tanks: a gray water tank and a black water tank

The gray water tank collects water from the shower and sinks. The black water tank holds waste from your toilet.

The black water tanks need to be emptied but also cleaned regularly. The buildup in the black water tank can cause unpleasant odors and blockages. A clean tank also helps the sensors work better, so you know how full the tank is.

A dump station is ideal for emptying your gray water tank, but not for emptying a black water tank. Emptying a black water tank at a dump station is problematic for two reasons:

• Not all dump stations have a hose connection
• The process can be more time-consuming

It's best to clean the black tank when your RV is fully hooked up to a water and sewage line.

You also don't want to use bleach or antifreeze. These can damage the rubber seals in your system. Simple Green All-Purpose Cleaner is a better choice as it doesn't contain the harsh chemicals commonly found in other cleaning products. It cleans and helps remove odors, leaving your RV smelling fresh.

How often you clean your tanks will depend on how much you use the RV. Deep clean after each trip, and don't store the RV with waste in the tank.

Emptying and cleaning frequency will vary based on how often you use your RV bathroom, and how many people are using it. It's recommended that you clean your RV tanks once a month in the summer and every other month in the winter.

Directions for Cleaning an RV Black Water Tank:

With a Sewage Rinse Outlet:

Tip: Use a separate garden hose for cleaning the black tank. Keep it separate from the freshwater hose.

Tip: It is recommended to dump when the tank is ¾ full.

Tip: Be sure to protect yourself from any drips, leaks, or splatters by wearing gloves.

1. Close valve. Close the gray water tank valve the night before cleaning the tank, so you can collect about half a tank of water. Usually, this can stay open when you're hooked up, but you'll want to accumulate some water to rinse the sewer line after you've dumped your black water tank.
2. Clean toilet. Click here for directions on how to clean the toilet with Simple Green All-Purpose Cleaner. Make sure you turn your bathroom fan off before you start this process (it should also be off every time you flush your toilet). Don't forget to open the gate valve and use a brush to scrub that area. After you've scrubbed, flush your toilet several times.
3. Connect hose. Connect the anti-backflush valve to the end of your garden hose. Attach the hose to the sewage rinse attachment on the RV and the other end to your fresh water source.
4. Start water. Turn the water on slowly, not all the way at once.
5. Open valve. Pull the black water tank valve to start draining.
6. Increase water. Slowly turn the water up for more flow. Let it run until the exiting water is mostly clear.
7. Close valve. Close the black water valve and wait for one minute.
8. Open valve. Open the black water tank valve again and let water flow through.
9. Close valve. Close the valve again and let the tank fill with water. Watch closely as the tank fills up. Don't leave it unattended, as you don't want the tank to overflow and pour water out of the vent on top of the RV.
10. Open valve. Once the tank is full, open the valve. The water should run mostly clear. If needed repeat steps 7-9.
11. Stop water. Turn off the water and let the remaining water drain out of the tank, then close the valve.
12. Open tank. Open the gray water tank valve and let it drain.
13. Add cleaner. Pour 2 ounces of Simple Green All-Purpose Cleaner into the toilet followed by a gallon of water.
14. Smell test. Perform a smell test to make sure any foul odors are gone.

Smell Test.

• Close all the windows in your RV, open your toilet's gate valve, and turn on your bathroom fan. There should be no odor coming from the black water tank.
• If there is still a smell, pour 2 more ounces of Simple Green All-Purpose Cleaner and one more gallon of water down your toilet.
• You can also put ice in your toilet. Pour about five 10-pound bags of ice down the toilet. Then drive the RV so that as the ice melts, it will shift around the bottom of the tank and scrape up any debris stuck on the bottom. Then drain the melted ice and any debris that was scraped up.
• For strong odors, pour 1 cup of Simple Green All-Purpose Cleaner and 1 gallon of hot water down the toilet, then slowly fill the tank with water. Let the solution sit in the tank for 24 hours. Drain it and do the smell test again.

Without a Sewage Rinse Outlet:

Tip: Use a separate garden hose for cleaning the black tank. Keep it separate from the freshwater hose.

Tip: It is recommended to dump when the tank is ¾ full.

Tip: Be sure to protect yourself from any drips, leaks, or splatters by wearing gloves.

1. Close valve. Leave the gray water tank valve closed overnight so you can gather about half a tank of water.
   • Tip: Usually, this can stay open when hooked up, but you should accumulate water to rinse the sewer line after dumping the black tank.
2. Clean toilet. Turn bathroom fan off before starting this process (it should also be off every time you flush your toilet). Open the gate valve and use a brush to scrub the area. After you've scrubbed, flush your toilet several times.
   • Tip: Harsh cleaning chemicals can damage the seal in the hole of the toilet that keeps odors from coming up from the black water tank.
3. Connect hose. Connect one end of the hose to a freshwater source. Feed the other end down the hole of your toilet.
4. Start water. Turn the water on fully to the highest. Make sure the hose is moving inside the tank. This ensures the water is reaching the spots that the built-in sprayer can't get to.
5. Open valve. Open the black water tank valve and let it drain. Let the water run for 10-15 minutes. Do not leave it unattended.
6. Close valve. Close the black water tank valve and leave it closed for about a minute.
7. Open valve. Open the valve again and let the water continue to run through.
8. Close valve. Close the valve again and leave it closed until the tank fills up with water. Watch closely and do not leave it unattended, as you don't want the tank to overflow and pour water out of the vent on top of the RV.
9. Open valve. Open the valve when the tank is full. The water should run mostly clear. If it's not clear, fill the tank again and repeat steps 6-8.
10. Stop water. Turn off the water and let the tank fully drain. Then close the valve.
11. Rinse line. Open the gray water tank valve to rinse the line.
12. Add cleaner. Pour 2 ounces of Simple Green All-Purpose Cleaner and a gallon of water into the toilet.
13. Smell test. Perform a smell test to make sure any foul odors are gone.

Tip: Never leave your black water tank valve open, even when you're fully hooked up. This will lead to what is known as "pyramiding," which is when all the liquid runs out of the tank, leaving the solids to build up and harden.