Water Heater Dielectric Union Replacement

Introduction

This tutorial provides a step-by-step guide on how to replace the dielectric unions, or nipples, on your water heater. This process is essential for maintaining the integrity of your water heater connections, especially if there is corrosion present. By following these instructions, you can ensure a proper seal and extend the lifespan of your water heater.

Step 1: Turn Off Water and Power

• Go outside and turn off the water supply to your water heater.
• If you have an electric water heater, turn off the circuit breaker connected to it.
• For gas water heaters, switch off the gas supply.

Step 2: Drain the Water Heater

• Locate the pressure relief valve on your water heater.
• Pull up on the valve to release any pressure and drain water from the heater.
• Use a drain tube to direct the hot water into a pan or bucket, as it can be very hot.
• Have a towel handy to soak up any spills.

Step 3: Remove Old Dielectric Unions

• Use a pipe wrench to loosen and remove the old unions.
• If you have a SharkBite connector, you may need to grind off the end to access the copper tubing.
• Carefully detach the old unions and inspect for any signs of damage or corrosion.

Step 4: Prepare New Unions for Installation

• Obtain new dielectric unions, ensuring they are the correct size (3/4 inch by 3/4 inch threads and approximately 5 inches long).
• Wrap pipe thread sealant tape around one side of the new union in a clockwise direction for a watertight seal.
• Apply blue thread sealant to the other side to prevent tape from getting stuck inside the water heater.

Step 5: Install New Dielectric Unions

• Align the new union with the correct direction of water flow. Check for any arrows on the union for guidance.
• Tighten the union securely, ensuring it is snug but not overly tight.
• If reusing old connectors, check the washers and replace them if they are uneven.

Step 6: Repeat for the Other Side

• Follow the same process for the other side of the water heater, ensuring all connections are secure and properly sealed.

Step 7: Restore Water and Power

• Close the pressure relief valve.
• Turn the ball valve back on to restore water flow to the heater.
• Turn the power back on by flipping the circuit breaker or relighting the gas.

Conclusion

You have successfully replaced the dielectric unions on your water heater. Allow the thread sealant to cure as per the manufacturer's instructions before using the heater. This repair not only prevents leaks but also enhances the overall efficiency of your water heater. Regular maintenance checks can help avoid similar issues in the future. If you encounter any problems or have further questions, consider consulting a professional plumber.