Anti-Scald Valve: What It Is, Why It Matters, and When to Replace It

An anti-scald or scald prevention valve is a device that regulates the temperature of water coming out of a plumbing fixture. It’s a critical safety device because it automatically prevents water from the shower, bath, or sink from getting hot enough to burn the skin. Ensuring that the valve is properly installed and functional is essential, especially for homes with children or elderly adults.

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Who Needs an Anti-Scald Valve and Where It Gets Installed

Anti-scald valves are beneficial for any home, but they are particularly important when the household includes young children, seniors, or individuals with disabilities. Home water heater temperature settings may reach as high as 140°F, and water at that temperature is hot enough to cause a second-degree burn in three seconds and third-degree burn in five seconds. Preventing the flow of such dangerously hot water from the shower, bath, or sink is an essential home safety measure, and for that reason anti-scald valves are required by most building codes throughout the United States.

These valves are often installed locally, beneath the sink or behind the shower or bath handle. They can also be fitted directly at the water heater to regulate the water temperature for the entire home, which is helpful when the water heater is purposely set at a higher temperature to prevent Legionella bacteria growth. In that circumstance, the home’s water supply is hot enough to kill bacteria, but the anti-scald device ensures water is at a safe temperature at point of use. 

What Building Codes and Safety Standards Say About Scald Prevention

Trade and engineering associations have increasingly incorporated scald prevention requirements into their codes and recommendations. The International Plumbing Code (IPC) and the Uniform Plumbing Code (UPC),for example, require anti-scald devices in showers and baths in all new construction and renovation projects. Most state and local governments likewise require anti-scald measures, though specific codes vary by location.

If your home is older and you haven’t updated the bathrooms or plumbing in some time, it’s possible that you don’t have anti-scald valves installed. While you’re not necessarily required to retrofit, it’s beneficial to do so for safety reasons. To install a pressure-balancing valve or thermostatic mixing valve, plumbing expertise is helpful, but with a little research you can make it a DIY project to save some money.

Symptoms Failing Anti-Scald Valves

Anti-scald valves can wear out over time. Corrosion, hard water, and normal wear and tear can eventually interfere with the valve’s ability to effectively regulate the water temperature. Signs that suggest the valve needs to be replaced include:

• Inconsistent or erratic water temperature. Drifting temperatures or sudden surges of hot or cold water are possible signs that the valve is no longer effective.
• Difficulty adjusting temperature. The valve may need to be replaced if you find the shower handle stiff or unresponsive, or if you need to move the handle a substantial amount to get a small change in temperature.
• Poor water pressure. As mineral deposits accumulate on the valve, water flow is inhibited, reducing water pressure.
• Visible corrosion or leaking. Any valve that is visibly deteriorating is more than likely on the brink of failure.

Some of these symptoms overlap with those of a failing water heater. Fluctuating water temperatures, for instance, could be related to either a bad valve or a malfunctioning water heater. If you have locally installed anti-scald valves, determine whether the problem is unique to a specific shower or sink or widespread throughout the home. If multiple plumbing fixtures are affected, first troubleshoot your water heater before you spend the money on replacing your anti-scald valves.

Replacing Anti-Scald Valves: Costs and What to Expect

In most circumstances, replacing an anti-scald mechanism is an easy job for an experienced plumber. The overall cost varies somewhat depending on the type of valve, accessibility, and local labor rates.

New pressure-balancing valves will cost around $100 to $250 each, parts and labor included. Thermostatic mixing valves are a little more expensive and can run from $200 to $400 per unit or more. Either type of valve can usually be installed in an hour or two. Costs and time required can increase if adjacent pipework needs to be replaced, or if tile or wall repairs are necessary.

Does a Home Warranty Cover Anti-Scald Plumbing Valve Repairs?

Plan specifics vary, but home warranties can cover anti-scald valves as part of their broader plumbing system coverage. With active coverage, you can simply submit a claim if the valve begins to malfunction after years of wear and tear. Your provider will tap its network of technicians to have the issue diagnosed and resolved, all at minimal cost to you.

The easiest way to explore Liberty Home Guard’s coverage options for plumbing systems and other home systems and appliances is to call us directly at (833)-543-7699. You can also peruse our plans and policies and request a free quote for coverage through our website.