Easy Steps to Replace Navien Water Heater Flow Sensor
Table of Contents
- Introduction
- Understanding the Issue
- Shutting Off the Water and Power
- Accessing the Flow Sensor
- Removing the Old Flow Sensor
- Installing the New Flow Sensor
- Checking for Leaks
- Troubleshooting Tips
- Conclusion
- Resources
How to Replace the Flow Sensor in a Navien Tankless Water Heater
Tankless water heaters are a popular choice for homeowners looking to upgrade their water heating system. They offer a more efficient and cost-effective solution compared to traditional tank-style heaters. However, like any other appliance, tankless water heaters are not immune to issues. One common problem faced by users is when the flow sensor fails to trigger the burners, resulting in a lack of hot water during low flow situations. Fortunately, replacing the flow sensor in a Navien tankless water heater is a relatively simple task that can be completed in a few easy steps.
Introduction
In this guide, we will walk you through the process of replacing the flow sensor in a Navien tankless water heater. We will provide detailed instructions, along with helpful tips and troubleshooting advice. Whether you are a seasoned DIYer or a first-time plumber, this guide will help you restore your hot water supply quickly and efficiently.
Understanding the Issue
Before we dive into the replacement process, let's take a moment to understand the issue at hand. When a Navien tankless water heater experiences low flow situations, the flow sensor may fail to trigger the burners, resulting in no hot water. This commonly occurs when using faucets with low water flow, such as kitchen sinks or bathroom sinks. However, when a high-volume flow, such as that from a bathtub, is detected, the flow sensor functions properly. This is a clear indication that the flow sensor needs to be replaced.
Shutting Off the Water and Power
Before beginning any work on the water heater, it is crucial to ensure your safety by shutting off the water and power supply. Start by pulling the power from the heater to avoid the risk of electrical shock. Then, locate and shut off both the hot water outlet and cold water inlet valves. Using pliers, open up the service caps on the valves to drain any excess water. Collect the water in a small container for disposal. This step may take a few minutes, so be patient.
Accessing the Flow Sensor
To access the flow sensor, you will need to remove the access cover of the water heater. In most Navien units, the access cover is secured by four Phillips head screws. Carefully remove these screws, taking note that the cover has a hooked lip to prevent it from falling off once the screws are removed. Once the screws are removed, lift off the cover and set it aside.
Removing the Old Flow Sensor
Inside the tankless water heater, you will find the cold water inlet that connects to the flow sensor. Follow the cold water line to locate the distribution manifold and the entrance of the heater core. Disconnect the three-wire harness attached to the flow sensor. Next, disconnect the blue cable by carefully pushing the connector and gently pulling it out. To remove the flow sensor, take off the stainless steel spring clip ring that holds it in place. Simply pop it out since it is spring-loaded. Finally, twist the flow sensor off carefully.
Installing the New Flow Sensor
Before installing the new flow sensor, it is essential to compare it with the old one to ensure they are identical. Look for any differences in design or connection points. The flow sensor plays a crucial role in determining the flow rate and inlet water temperature, which directly affects the heater's operation. Once you have verified that the new flow sensor matches your model, you can proceed with the installation.
To begin, remove the inside o-ring from the old flow sensor and slide it onto the inlet pipe on the heat exchanger. This ensures a proper seal. Then, carefully slide the new flow sensor onto the inlet pipe, making sure the gasket is lined up correctly. Use a Phillips number two screwdriver to reinstall the four screws, ensuring they are snug but not over-tightened.
Checking for Leaks
After installing the new flow sensor, it is crucial to check for any leaks before restoring power and water supply to the heater. Use a paper towel to dry off any water that may have come in contact with the body of the water heater or the low-voltage wiring. This step is essential to prevent electrical, safety, or performance issues. Once you are confident that everything is dry, close off both the hot and cold drain service valves and screw the caps back on. Use pliers to snug up the caps without applying excessive force.
Troubleshooting Tips
If you encounter any issues after replacing the flow sensor, there are a few troubleshooting steps you can take to resolve them. First, ensure that the flow sensor is installed correctly and that all connections are secure. Check for any damaged wires or loose connections. If the problem persists, consult the manufacturer's troubleshooting guide or consider contacting a professional plumber to diagnose and fix the issue.
Conclusion
Replacing the flow sensor in a Navien tankless water heater is a straightforward task that can be completed in a matter of minutes. By following the steps outlined in this guide and taking necessary safety precautions, you can effectively restore hot water to your home. Remember to always consult the manufacturer's instructions and seek professional assistance if needed. With a newly installed flow sensor, you can enjoy uninterrupted hot water for years to come.
Resources
Highlights
- Learn how to replace the flow sensor in a Navien tankless water heater
- Simple step-by-step instructions for DIY enthusiasts
- Troubleshooting tips for common issues
- Ensure safety by shutting off the water and power supply
- Reinstall the o-ring for proper sealing
- Check for leaks before restoring power and water supply
- Troubleshoot problems and seek professional assistance if needed
FAQ
Q: How long does it take to replace the flow sensor in a Navien tankless water heater?
A: The replacement process typically takes less than 10 minutes to complete.
Q: Where can I purchase a replacement flow sensor for my Navien tankless water heater?
A: You can purchase a replacement flow sensor from an authorized Navien dealer or through the official Navien website.
Q: What should I do if the flow sensor replacement does not solve the issue of no hot water?
A: If replacing the flow sensor does not resolve the problem, it is recommended to consult the manufacturer's troubleshooting guide or seek assistance from a professional plumber.
