Is your RV's hot water feeling a little…luke-warm? Or maybe your water pressure isn't what it used to be? The culprit might be mineral buildup in your tankless water heater. Don't worry, flushing it out is easier than you think! This guide will walk you through the process step-by-step. 

## Why Flush Your RV Tankless Water Heater?

Tankless water heaters are fantastic for saving space and providing on-demand hot water in your RV. However, they are prone to mineral buildup from hard water, especially if you frequently camp in areas with known hard water. This buildup can: 

*   Reduce water flow and pressure.
*   Lower the water temperature.
*   Damage the heating element, leading to costly repairs or replacement.
*   Void your warranty if not maintained per manufacturer instructions.

Flushing your tankless water heater regularly (typically every 6-12 months, depending on your water source) is crucial for maintaining its efficiency and extending its lifespan. 

## What You'll Need

Before you get started, gather these supplies:

*   **Submersible Pump:** A small utility pump (like a sump pump) will circulate the cleaning solution. Look for one with hose adapter fittings.
*   **Two lengths of Hose:** Garden hoses, usually about 3-5 feet each, with appropriate fittings to connect to your pump and water heater.
*   **Bucket:** A five-gallon bucket is a good size to hold the cleaning solution.
*   **Tankless Water Heater Flush Kit (Optional):** Some kits are available and include the pump, hoses, and cleaning solution all in one package. This simplifies the process.
*   **White Vinegar:** This is the most common and environmentally friendly cleaning solution. You can also use a commercially available descaling solution specifically designed for tankless water heaters.
*   **Adjustable Wrench:** For loosening and tightening hose connections.
*   **Gloves and Eye Protection:** To protect yourself from the cleaning solution. 

## Step-by-Step Flushing Guide

Here's how to flush your RV's tankless water heater:

### 1. Turn Off the Water Heater and Water Pump

*   Locate the switch or breaker for your water heater and turn it OFF. This is extremely important!
*   Turn off your RV's water pump as well. 

### 2. Disconnect the Water Lines

*   Locate the cold water inlet and hot water outlet lines connected to your water heater. These are usually clearly marked.
*   Using your adjustable wrench, carefully disconnect both lines. Have a towel handy to catch any residual water. 

### 3. Connect the Hoses and Pump

*   Connect one hose to the cold water inlet of the water heater.
*   Connect the other end of that hose to the outlet of your submersible pump.
*   Connect the second hose to the hot water outlet of the water heater.
*   Place the other end of that hose into the bucket.

### 4. Prepare the Cleaning Solution

*   In the bucket, mix your cleaning solution. A common ratio is 1 gallon of white vinegar to 1 gallon of water. If using a commercial descaling solution, follow the manufacturer's instructions. 

### 5. Circulate the Cleaning Solution

*   Submerge the pump in the bucket with the cleaning solution.
*   Plug in the pump and let it circulate the solution through the water heater for at least 30-60 minutes. This will help dissolve the mineral buildup. Consider reversing the flow direction every 15 minutes by swapping the hoses. 

### 6. Flush with Fresh Water

*   After circulating the cleaning solution, unplug the pump and remove it from the bucket.
*   Empty the bucket and rinse it thoroughly.
*   Fill the bucket with fresh, clean water.
*   Reconnect the hose from the hot water outlet of the heater into the bucket. Make sure you’re ready to dispose of the flushed waste water. 
*   Submerge the pump in the fresh water and plug it in again. Circulate the fresh water through the water heater for 10-15 minutes to rinse out any remaining cleaning solution. 

### 7. Reconnect the Water Lines

*   Disconnect the hoses from the water heater. Reconnect the cold water inlet and hot water outlet lines, making sure the connections are secure.

### 8. Turn Everything Back On

*   Turn on your RV's water pump.
*   Check for any leaks around the water line connections. Tighten if needed.
*   Turn the water heater back ON.

### 9. Test the Water Heater

*   Run the hot water in a faucet to ensure the water heater is working correctly. It may take a few minutes for the water to heat up. 

Congratulations! You've successfully flushed your RV's tankless water heater. Now you can enjoy hot showers and optimal water pressure on your next adventure. Remember to schedule regular flushes to keep your system running smoothly!


Learn how to flush your RV tankless water heater to remove mineral buildup and maintain optimal performance. A simple guide for RV owners.

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