Tempering Valve: What It Is and Why It Matters

We’ve all had those chilly winter mornings when the thought of a warm shower seems like the perfect way to start the day. But imagine if you’re jolted awake by a rush of scalding hot water instead. This uncomfortable experience, familiar to some, underscores the significance of an unsung hero in our plumbing systems—the tempering valve. This article will explain how a tempering valve works and why it is important for your home. 

What Is a Tempering Valve?

A hot water tempering valve, also known as a water mixing valve, is critical in controlling the balance of hot and cold water. Its primary function is to merge the boiling water from your heater with cold water to ensure the hot water supply at your taps maintains a consistently tempered, safe temperature.

This important feature prevents hazardous situations due to extremely high water temperatures, boosting safety when utilising your hot water systems. If you’ve ever experienced an unexpected surge of scalding hot water during a relaxing bath or while rinsing dishes, you’ll understand the importance of a reliable hot water tempering valve. 

How Does a Tempering Valve Work?

The importance of a tempering valve can’t be overstated despite its relatively simple role behind the scenes. Its duty lies in the continuous assurance of safe and comfortable water temperatures in your household. Whether for your morning shower, your children’s bath in the evening, or handling your kitchen chores, the tempering valve ensures reliability and safety. 

Implementing a hot water tempering valve addresses more than just safety concerns. It enhances the convenience factor in your home and boosts the efficiency of your hot water systems. 

Installing this valve reduces the need for repeated manual adjustments to the water temperature, effectively saving water and contributing to a more eco-friendly household.

This is especially true for homes with tankless continuous flow models, where precise control through tempering valves can offer significant advantages. Comfort, safety, and efficiency are essential to cultivating a happy home environment, and a tempering valve is instrumental in delivering these attributes. 

Here are a few more responsibilities of tempering valves: 

• Optimal Temperature Control: A tempering valve accurately blends hot and cold water to provide a consistent, safe output temperature. This reduces the risk of accidental scalding while ensuring maximum comfort.
• Boosted Efficiency: Saves water and reduces energy consumption by eliminating the need for manual adjustments. This can reflect reduced utility bills, making the valve a cost-effective addition to your household.
• Additional Deliverable Hot Water: Allows the water heater to be set at a higher temperature, delivering more hot water without risking scalding. This is achieved by blending in cold water to achieve the desired temperature downstream.
• Prevention of Hot Water Burns: Tempering valves are specially equipped to deal with unexpected pressure fluctuations, which can lead to hot water burns. A built-in anti-scalding function shuts off the water if the temperature exceeds a safe limit.
• Customisable Options: Many valves come with a lockable dial knob to tailor the output temperature to your personal preference.

The Australian Standard AS 3500.4 notes hot water delivery in bathrooms should not exceed 50 degrees Celsius to prevent scalding.

What Are The Different Types of Tempering Valves?

Mixing Valve

A mixing valve is a 3-way valve that blends hot and cold water to achieve the desired output temperature. These valves are commonly used in water heating applications to regulate the water temperature and provide consistently tempered hot water to your home. The tempering valve receives hot water from the water heater and cold water from the main supply, combining them in the valve body to produce a balanced output of tempered water.

Various types of mixing valves are available in the market, each with distinctive features and functionalities. However, their primary function remains the same: maintaining a stable output temperature and reducing the risk of scalding incidents.

Thermostatic Mixing Valve

A more advanced type of mixing valve is the thermostatic mixing valve (TMV). The TMV uses a temperature-sensitive element to control the mix ratio of hot and cold water. These valves constantly adjust the flow rates of hot and cold water, responding to changes in the supply temperature to deliver a consistent output temperature.

Thermostatic mixing valves are particularly useful in applications where maintaining a constant water temperature is crucial for safety, such as hospitals or aged care facilities. You can find more information about TMVs in the Watts reference tools available online.

The Role of A Tempering Valve in Hot Water System Replacement

When replacing your hot water system, incorporating a tempering valve is integral to the process. Here’s why:

Right Hot Water System Selection: Choose a hot water system suitable for your energy source, location, and budget, considering the crucial role of a tempering valve regardless of whether you select a gas, electric, solar, or heat pump system.

Proper Size Determination: Ensure your new tank meets your hot water needs to avoid energy waste or shortages. A tempering valve will consistently control the water temperature, irrespective of the tank size.

Trusted Professional Installation: An experienced plumbing company will install the system efficiently, safely, and correctly incorporate the tempering valve, preventing potential issues like leaks or system failures.

Compliance with Regulations: When following local building codes and regulations during the replacement process, remember that using a tempering valve is often not just a recommendation but a regulatory requirement.

Applications and Regulations

Did you know that in Australia, tempering valves aren’t just highly recommended but actively regulated by the Plumbing Code of Australia? This code is there to help enhance safety and prevent unfortunate accidents, stipulating that the water temperature from any installed tempering valve should remain consistent, with an accuracy of about 3°C +/-.

Now, let’s talk about your household water heater. To keep harmful bacteria like Legionella at bay, you need to set the thermostat of your hot water system tank at 60°C or higher. This is about complying with valve regulations and ensuring that hot water storage is safe for everyone within your home or commercial establishment. It’s a little piece of information that goes a long way. 

Remember, though, that tempering valves tend to have shorter life spans than Thermostatic Mixing Valves (TMVs) on average. 

Typically, when the time comes, they are replaced rather than repaired. But regardless of their lifespan, both valves are important in ensuring a stable, scald-free water temperature. It’s always better to be safe, wouldn’t you agree?

When to Consult a Professional Plumber

Recognising when to call upon a professional plumber is crucial to maintaining the performance and lifespan of your tempering valves, particularly if you have a hot water tempering valve in your home. Here’s when you should reach out for help: 

• Your tempered hot water supply doesn’t meet the desired temperature: This may signal an issue with your tempering valve or water heater. Over time, the mechanical components of your valve can wear out, or your valve’s setting may need to be corrected.
• You’ve experienced sudden changes in hot water temperature: Indeed, this problem can point to pressure fluctuations in your water supply. An anti-scald valve, integral to many tempering systems, guarantees the water doesn’t exceed 120F. This effectively prevents hot water burns due to abrupt pressure changes. However, if this function fails you, it’s important to consult a professional plumber immediately.
• You’re installing a new water heater: Whether switching from a traditional water heater to a tankless continuous flow model or upgrading your old unit, a plumber can provide expert guidance. Going tankless is likely to improve your household’s energy efficiency. However, it is also mandatory to ensure the installation of a tempering valve on all new water heater installations, so don’t forget this crucial addition.
• You notice a decrease in energy efficiency: In this situation, turn up the water heater thermostat to 140 degrees and use a mixing valve to provide more deliverable hot water at the desired temperature. But, if this doesn’t help, it could indicate a faulty tempering valve that needs immediate attention.

Key Takeaways

• A tempering valve is crucial in your home’s hot water system. It blends hot and cold water to a predetermined, safe temperature.
• The two main tempering valves are the ‘mixing valve’ and the ‘thermostatic mixing valve’.
• Proper use of a tempering valve prevents scalding, promotes energy efficiency, and extends the lifespan of your hot water system.
• The application and implementation of tempering valves must abide by specific Australian regulations to ensure safety.
• When replacing your hot water system, a tempering valve is vital in maintaining safety and enhancing system performance.
• Tempering valves have different connection types, including Union Sweat, Union Threaded, Threaded, and Thermostatic Mixing Valves.
• Certain brands, like the Cash Acme Tank Booster, offer enhanced features such as a lockable adjustment for added safety.
• Newer water heaters must have better insulation for increased energy efficiency, and operating at 95 degrees can confer energy savings.
• Depending on your specific needs, plumbing mixing valves come in two categories: whole-house and point-of-use.
• Tempering valves can be purchased through wholesale retailers and incorporated with a flexible connector for easy installation.
•  If you live in Canberra and experience difficulties with your tempering valve or need professional assistance with installation or replacement, don’t hesitate to contact us.