Is It Bad To Turn Your Hot Water Heater All The Way Up?

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In this article, we will talk about what is the best temperature for your water heater so that you can maximize its life, minimize your electricity bills, and burst some common myths of using the hot water heater.

Turning your hot water heater all the way up is bad because it will reduce your heater’s life, increase your electricity bill, and could cause scalding.

It takes only three to five seconds to burn your skin severely and according to the research of the American Burn Association, up to 41% of the homes were inspected to be operating at an unsafe level.

Using a Water heater to its maximum capacity will affect its service life and increase your bill.

The rule of thumb is, safe hot water temperature should be around 120 degrees Fahrenheit. That means it should be set below 120 degrees, which may vary depending on weather, brand, need, and age of family members.

Safe hot water temperature should be around 120 degrees Fahrenheit

Guidelines from the U.S. Department of Energy recommend the 120 degree-mark for maintenance and saving purposes but most of the water heaters automatically set it to 140 degrees Fahrenheit which is higher than necessary. Keeping the water heater at the recommended temperature slows down mineral buildup and corrosion in containers and pipes.

Apart from the dermatological harms and equipment damage, there are more unseen factors that you should know about.

Will Turning up the Water Heater Make Hot Water Last Longer?

Absolutely it will last longer as we discuss in our article about turning up the water heater to get more hot water.

Will Too Much Hot Water Damage Your Pipes and Valves?

The plumbing system in our homes is divided into two parts, the hot water supply, and the cold water supply. Most of the homes have PVC pipes installed for both hot and cold water supply. If you are using PVC pipes at your place for hot water, then you should never let the water temperature above 140 degrees Fahrenheit because it can damage your pipes.

The glue at the joints is even more susceptible to extremely hot water, and even if you’ve sent boiling water down before and haven’t noticed any ill effects, know that the damage could be cumulative.

All plastic pipings have a maximum operating pressure and temperature at which they can be used for 50 years. As the temperature increases, the maximum allowable pressure rating decreases to a point where the pipe can not handle the water temperature anymore, and this temperature is called maximum allowable operating temperature.

Different piping materials have different operating temperatures like PPR’s (polypropylene Random Copolymer) maximum operating temperature is 158 degrees Fahrenheit and CPVC (Chlorinated Polyvinyl Chloride), on the other hand, has 180 degrees Fahrenheit.

Most people use extremely hot water to remove clogs from the drainage system but they are just moving the clog deeper. The boiling water does not solve your drainage problem until a mechanical drain cleaner comes to remove it.

So they need to stop this because it leads to a new piping problem i.e. corrosion. Heat accelerates the process of corrosion and increases the susceptibility of piping material to corrosion when exposed to hot water.

Chlorine and chlorine dioxide are used in piping material as disinfectants to remove dirt and other sediments to make water pure. When the water comes in the contact of chlorine then it forms a hypochlorous acid that can easily break the protecting layer of pipes and it takes only nine months to form this acid.

This corrosion is more usual in hot water lines because the hot water makes the chlorine more vicious and degrade the material. After some time, the degraded material corrodes away and the pipe wall thins, weakening it and leading to leakages.

Now you might be wondering why we are not using iron and steel pipes in our plumbing system. The answer is very simple, these pipes are corrosive with normal water so how they will persist with hot water and their durability is less and are very expensive in comparison to plastic pipes.

In a nutshell, we can say that using too hot water in pipes, mixing valves and, taps damage the whole plumbing system, but we can avoid those damages if we work smartly. With the word “smartly”, we mean that you must use the piping material of right operating pressure and temperature according to your need for hot water.

Plastic Pipe MaterialOperating Temperature With PressureOperating Temperature Without Pressure
ABS – Acrylonitrile butadiene Styrene100180
PE – Polyethylene100180
PVC – Polyvinylchloride120140
CPVC – Chlorinated Polyvinyl Chloride180180
PB – Polybutylene180200
PP – Polypropylene100180
SR – Styrene Rubber Plastic150

The above table shows the operating pressure and temperature of plastic pipes of different materials. You can check this table when you install a new plumbing system in your house.

Will My Water Heater Explode If I Turn It All The Way Up?

You might have heard the stories about exploding water heater in someone’s home. Are they true? Yes, they are TRUE. A water heater can explode.

Let’s find the reason behind this, but before that, we need to understand it’s working.ifferent

There are two types of water heater – Gas and Electric. Different models of water heater work in slightly different ways, although they all operate on similar principles.

A gas heater uses a burner to heat stored water inside the tank while an electric heater uses coils to heat the water. When the water heats up to the desired temperature, as preset by the user, the burner cuts off.

Gas water heaters need to exhaust carbon monoxide through the flue, so If your flue is damaged, carbon monoxide can leak into your home, hence, you need to install a carbon monoxide detector to avoid any issues with potential leaks if you use a gas water heater.

If you are using a water heater at a very high temperature or the pressure releasing valve is not working properly, then it can surely explode. And this can happen with both, gas and electric water heater. The pressure releasing valve may malfunction if the pipe is blocked or the pressure doesn’t get released from the gas valve.

As the water heats up, some amount of gas is formed. And when the heat and pressure become too much, then it attempts to release the pressure through the relief valve. If the valve is blocked or broken, the internal pressure will rise until the water heater explodes.

The damage from the explosion can be very destructive, which can compromise your entire house. Although the chances of this are very low, when it happens, it operates the same as a rocket.

Always check the pressure releasing valve to ensure it is in good condition. If you find any defect, then contact an expert, because it can be very dangerous. The best precaution that you can take is to set the temperature no higher than your manufacturer suggested.

Will it be expensive to Turn The Water Heater all the Way Up?

If you want to save energy and cut down your household utility bills then lowering the water heater temperature can help. Most manufacturers have the thermostat set at a default temperature of 140 degrees. The water temperature this high results in energy losses and may cause serious injuries to vulnerable members of your household.

Lowering the temperature is only one of the ways you could save on your energy bills.

By setting up the water heater to the suggested temperature, you can save the appliance’s energy consumption by up to 10 percent. A water heater consumes 25 percent of the total energy usage in most households and lowering the temperature can provide significant cost savings.

Water above 120 degrees causes excessive heat loss and If you have a storage water heater then it uses a large amount of electricity. The reason is simple, each time you turn on a hot water tap in your home it draws some amount of water from the tank.

The emptied tank is refilled by cold water that dilutes the hot water, so the whole tank must be reheated again to maintain the high temperature.

Some effective ways can reduce your electricity bills significantly. You can cut your energy bill by taking short showers, decreasing the temperature of your water heater, fixing leaks, and insulating your hot water storage tank.

Use these tips for a year you will find a huge difference in your energy bill readings.

Myths about water heater

Myth 1: A new water heater saves more energy

A new water heater saves marginal energy. You can save up to $5 per month.These savings don’t take into account the additional cost of the new water heater. The thing that matters the most is how you utilize hot water in your home.

Myth 2: Older water heater means dirty water

People usually think that after some time, water heaters become rusty and the dirt is accumulated around the pipes and inside of the tank that leads to dirty water. But water heaters are designed to work for years. If you find rust and dirt coming out with the water, call your service provider for its servicing.


We are sure after reading all the facts and stats, you will be able to make an educated decision on how to handle your water heater. What temperature is suitable for you. And How much you can save in the long run. Also, we’ve busted some common misconceptions about overheating the water and its effects on plumbing systems. From now on, we hope you’ll use this appliance more smartly.

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