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Water Heater 101: How to Increase Your Hot Water Capacity with a Mixing Valve 

Jan 2, 2024

Hello, I’m Steve from Fast Water Heater Company, and today I’m excited to share with you a handy tip on how to get more hot water from your water heater using a mixing valve. 

The Challenge of New Efficiency Standards 

In April 2015, new efficiency standards were introduced for water heaters in the United States, requiring them to be more efficient. While this is great for energy conservation, it has led to water heaters being larger in size, which might not fit in some existing spaces. This situation could result in having a smaller water heater, and consequently, less hot water than you’re accustomed to. 

The Solution: Mixing Valve 

But there’s a solution! By adding a mixing valve, you can significantly increase the hot water available in your home. Here’s how it works: 

Components of a Mixing Valve 

1. Cold Water Supply Valve: 

This is installed on the cold-water nipple of the water heater. 

2. Hot Water Mixing Valve: 

This goes on the hot water outlet of the water heater. 

3. Cold Water Transfer Tube: 

Connects the system together. 

Once installed, these components work together to enhance your water heater’s capacity. 

Adjusting the Temperature 

After installation, it’s important to adjust the temperature: 

1. Turn up your water heater to 140 degrees. 

2. Use the mixing valve to adjust the output temperature. Aim for about 120 degrees. 

3. Check the water temperature with a thermometer at your fixture and adjust accordingly. 

Enjoy More Hot Water 

With the mixing valve now installed and adjusted, you can enjoy up to 25% more capacity from your water heater.  

Key Steps for Installation 

1. Shut off the water to the heater (turn off the breaker for electric heaters or set the gas control to vacation mode for gas heaters). 

2. Partially drain the water heater to relieve pressure. 

3. Install the mixing valve components. 

4. Refill the water heater and turn the power or gas back on. 

5. Set the water heater temperature to 140 degrees and adjust the mixing valve to about 120 degrees. 

6. Finally, test the water temperature at your fixtures. 

Check Out Our Video! How To Get More Hot Water From Your Water Heater:

Understanding the Risks: Increased Operating Costs and Wear on Your Water Heater

While installing a mixing valve and adjusting your water heater’s temperature can provide more hot water, it’s important to be aware of the potential risks associated with operating the tank at higher temperatures. Here are some key considerations:

  1. Increased Fuel Consumption: Operating your water heater at a higher temperature, such as 140 degrees, naturally requires more fuel to maintain that temperature. This increased fuel consumption can lead to higher operating costs over time.
  2. Enhanced Wear and Tear: The higher temperature setting can cause more frequent burning on the surface of the tank. This not only increases the wear and tear on the surface plate but also affects the overall longevity of the water heater. The rate of wear and tear can increase significantly depending on the temperature setting.
  3. Risk of Overworking the Heater: Most water heaters are designed to operate efficiently at a maximum temperature of around 125 degrees. Any setting above this is considered excessive and can lead to constant expansion and contraction of the tank’s metal components during heating intervals. This constant fluctuation can be a primary cause of failure in water heaters.
  4. Safety Concerns: It’s also crucial to consider the safety aspects. Operating the water heater at excessively high temperatures can pose risks, such as scalding, especially in homes with children or elderly individuals.

Balancing Efficiency and Longevity

To balance the benefits of increased hot water capacity with these risks, it’s important to:

  • Monitor and Adjust: Regularly check and adjust the temperature settings to ensure they are not excessively high.
  • Regular Maintenance: Schedule routine maintenance for your water heater to check for any signs of wear and tear or potential issues.
  • Consult Professionals: If you’re unsure about the appropriate settings or have concerns about your water heater’s performance, it’s always best to consult with a professional.

At Fast Water Heater Company, we understand the importance of having a reliable and efficient water heater. Our team is here to help you make informed decisions about your water heater’s operation and maintenance. Feel free to reach out to us for any advice or assistance you might need.

Call (425) 636-7038
for fast service


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