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Why Is My Hot Water Running Cold? (Quick Answers)

While taking a hot and refreshing shower, the worst you can experience is if all of the sudden hot water starts running cold leaving you all frozen in the shower.

This incident would make you demand the answers to the query, “why suddenly the hot water is running cold?” So, let’s explore the answers ahead.

7 Reasons For Hot Water Running Cold: 

Burned-out or defective heating element, a build-up of sediment, broken dip tube, malfunctioning thermostat, small-sized hot water tank, old water heating system, and overusing hot water are the top 7 reasons among multiple reasons that cause a sudden running of cold water instead of hot water.

As you can see, several reasons directly are responsible for hot water running cold, so let’s have a look at the explanations listed below to get a detailed insight into the reasons.

Burned-Out Or Defective Heating Element: 

A burned-out or defective heating element loses its efficacy in heating the water in the water tank. As a result, the water temperature in the taps goes down quickly and cold water starts to run out of the tap, or the water stops heating at all.

Wear and tear as well as an accumulation of hard water sediment in the water tank are the most potential reasons that cause a burned-out or damaged heating element.

A Build-Up Of Sediment:

Water carries solid materials while flowing through the pipeline into several places in your house. Particularly, if you receive hard water, it carries calcium, iron, and magnesium in a large amount.

Gradually, these minerals accumulate and settle at the base of the tank while occupying space and leaving less room for hot water in the tank. Also, the water heater can lose its efficiency in heating water. As a result, cold water starts to run instead of hot water. 

Broken Dip Tube: 

The dip tube is basically a plastic pipe that primarily functions to supply the coming chilled water to the bottommost of the water tank where the heating element is situated.

As the water heats, warm water reaches the tank’s top where it goes out of the tank through a hot water outlet. So when the dip tube gets broken, cold water begins to mix with the heated water and runs through a pipeline from the water outlet.

As a result, cold water starts flowing instead of hot water after a short period of time. 

Malfunctioning Or Non-Functioning Thermostat:

Thermostats are designed for relaying information about at what temperature the water should be heated and when the heating elements need to start up. But the thermostats don’t heat simultaneously, instead, they pass information to one another.

For example, if the upper thermostat perceives that the water is chilly than regular, it passes this information to the lower level thermostat to make an adjustment accordingly.

However, when this automatic procedure breaks down due to malfunctioning or non-functioning thermostats, hot water can consistently go cold.

Small-Sized Water Tank:

A smaller-sized water tank that doesn’t meet the increasing need for warm water in your household can be a why hot water is running cold often. Specifically, if your family is growing, you are most likely to encounter that warm water is running out quickly. 

Overuse Of Hot Water:

If multiple people in your household have taken a shower in a short stretch of time, simply hot water will run out because hot water will be used up mostly and the last person to take shower will be exposed to cold water. 

Moreover, if you use appliances that use hot water like a dishwasher or a washing machine, it increases the hot water usage, which eventually makes hot water run cold suddenly. 

Old Water Heating System: 

A water heater comes with a maximum lifespan of about 10 years. Over time, continuous usage, sediment build-up, corrosion, and any damaged component keep lessening its lifespan.

Thereby, after reaching its average lifespan, a water heating system loses its efficiency and full functionality to heat water like usual, which can cause a running of cold water instead of hot water.

How Do You Fix Hot Water From Being Cold Fast?

Below different ways to fix different issues that cause hot water to get cold fast have been listed for your convenience. 

Frequently Check The Heating Element:

You are strictly advised to keep checking the heating element’s voltage frequently by using a continuity tester or multimeter so that you can stay updated on whether the heating element is functioning properly or not.

If the heating element is totally burned-out or faulty due to wear and tear, you must replace it. 

Drain Or Flush The Water Tank: 

Draining out the sediment build-up is the solution that will solve the issue of hot water getting cold fast. You can also install a filter on the water heater so that solid materials can’t make their way to the water tank. 

And if you receive hard water, think about putting a water softener to break the sediment buildup in the water tank. 

Replace A Broken Dip Tube: 

You just need to replace a broken dip tube if it’s the actual reason that’s causing hot water to go cold quickly. And seek an expert’s help to replace the dip tube because it’s situated at the base of the tank, therefore, excerpts can deal with it more efficiently than you. 

Replace Malfunctioning/Broken Thermostats: 

Malfunctioning or faulty thermostats always need to be replaced with new ones to prevent hot water from being cold fast.

However, before you change the thermostats, turn to an expert to learn what model of thermostats you will require and what are the prerequisites for installing the right system to the water system. 

Get A Bigger Water Tank: 

If a small-sized water tank is responsible for hot water running cold, fix this problem by installing a bigger-sized water tank that will match the requirement for hot water for your household. 

Or else, you can set up an additional water tank. Take a plumber’s help to connect the new and old water tanks, which will raise the capacity of holding more hot water. 

Give Time For The Tank To Heat Water: 

Allow your water tank to have sufficient time so that it can heat more water to fulfill your need for hot water, even if people in your home are overusing hot water or you are appliances that use warm water to do their washing jobs.

Replace Old Water Heating System: 

First, contact an expert to find out if the water heating system has passed its lifespan to function appropriately or not. If it’s old enough and not working, you should get a new water heating system.

What Are The Signs That Your Hot Water Heater Is Going Out? 

To help you perceive the symptoms better of your hot water heater going out, here the most potential signs are listed. 

Not Getting Enough Hot Water: 

A properly functioning water heater should be able to supply sufficient hot water to your family throughout the day while doing chores using hot water.

But while showering if you are exposed to cold water frequently or if it’s taking forever to heat water again after hot water has run out, take it as a sign of your water heater going out. 

Leaked Water Heater: 

If you aren’t getting enough hot water but the water bill is high, it can happen due to a leakage in the water heater because the hot water heater can leak as it gets older. And it’s a sign of a failing water heater. 

Rusty Water: 

As a water heater passes its lifespan, it gets rusty inside. And the rust finds its path into the hot water supply. As a result, if you receive rusty or discolored water, it’s most likely due to a failing water heater. 

Old Water Heater: 

If your water heater has passed the average lifespan of 10 years, it naturally will go out while showing several signs of a failing water heater. So after 10 years of time, you just need to get a new water heater. 

Odd Noises From The Water Heater: 

If odd sounds are coming out from your water heater, it can be one of the signs of a water heater having some internal issues, and it’s about to fail soon.

What Is The Average Lifespan Of A Hot Water Heater? 

A hot water heater comes with a lifespan of about 10 years on average. However, some hot water heaters can last for 8-12 years, depending on the brand and how the water heater is maintained over the years.

Final Thoughts

Hot water runs cold due to several reasons, but among them, burned-out heating element, accumulated sediment, damaged dip tube, non-operating thermostat, small hot water tank, worn out/old water heater, and over usage of hot water are considered to be the main reasons.