Tankless Water Heater Goes Cold After A Few Minutes

Many consumers complain that tankless water heater goes cold after a few minutes. Unexpectedly that’s true. But there are some specific ways to solve it. A water heater is not less than an essential home appliance, and It can be with a tank or without a tank. Gas or electricity is the fuel for the water heater, but the gas model is an older one.

Tankless electronic is the latest version of the water heater. People use it for their comforts. Especially in the cold season, consumers are much dependent on it. The user gets irritated when hot water became cold just after a moment. When it happens regularly, then they get frustrated.

The Tankless Water Heater Goes Cold After A Few Minutes

A new tankless water heater provides hot water smoothly. But as time flies water heater may have a problem. One of the problems is tankless water heater goes cold after a few minutes. I am now describing some reasons for hot water became cold:

Hot Water Become Cold After Lasting a Few Minutes

•    Dip tube: It is a tube that attaches to the inlet valve of cold water. Pushing cold water at the bottom of the tank, that’s deep tube’s main job.

•    Heating elements: Electric water heater has upper and lowers heating elements. After using it for years, these elements got damaged and failed to heat water.

•    Thermostat: A thermostat controls the heating elements of the water heater. What if the thermostat gets damaged?  It loses power to run heating elements. Thus, water remains cold.

•    Coldwater sandwich:  Using multiple appliances at a time creates problems in heating water. It keeps the water heater in pressure. So you get cold water after hot water.

•    Hard water: heat exchanger system becomes imbalanced due to hard water. Later it may fail to heat water.

•    Ventilation: The water heater uses a ventilation system to continue heating water. The blocked vent prohibits the ventilation system.

    Dirty Burner: Burner uses to heat water. If ut geta dirty then water heating process becomes slow.

    Fuel supply issue: water heater needs fuel ( electricity or gas) to run the system. But for any reason, supply may get restricted.

•    Defective ignitor: Without an ignitor, you can not think of heating water in the gas water heater. Sometimes it gets damaged.

Preventing Water From Getting Cold

You don’t need to replace your water heater for some problems. You can fix them quickly by yourself or a plumber. Describing below the solution tips:

•    Get a dip tube: It may get old and isolated. It is available in the market. Get it replaced by a new one to have hot water.

•    Installation: Consumer installs water heater near appliances to avoid creating pressure. You can use multiple appliances easily.

    Storage: Get a tank to store hot water. Ou may get warm water without power for a limited time.

Tankless Water Heater Goes Cold

•    Heating elements: Elements lost the ability as they get older. The water healing process becomes slow. Before it fails to heat water, you should replace the parts.

•    Fuel supplying continues: Water heater runs on electricity or gas. You have to ensure their continuous supply.

    Thermostat: As we know, it controls heating elements, so it is imperative.  Symptoms of the thermostat not working should not be neglected. Buy a new thermostat instead of the water heater.

•    Water softener: It is used widely by consumers to solve complex water problems. For hard water, malfunction happens in a heater. A water softener clears the pipe and makes the water taste better. It clears the path for a valve to supply water. To get good quality hot water, you should use a water softener.


01. Why my electronic or gas tankless water heater goes cold?

Ans. Hot water turns cold and again hot after a while because of the cold water sandwich problem. Temperature fluctuations happen during the coldwater problem. A tankless water heater can not heat water instantly on multiple devices. When we use multiple appliances simultaneously, the heater does not get enough time to heat water. A dirty water filter is also a reason for cold water.

02. Why do I get cold water after one shower of hot water?

Ans. The most reason for losing hot water is sediment. It may build up slowly in a water heater. Regular maintenance is a must to prevent sediment. It leads cold water to shower instead of hot water.

03. Why does my tank-less water heater not remain hot like before?

Ans. Tankless water heater does not have a tank to store hot water. It heats water on demand. When we use multiple appliances at a time heater gets pressured. Thus, it can not supply hot water. Hard water, heat elements damaged, blocked vent, etc., can be other reasons. Keep heater near appliances, maintained properly, get a plumber, etc., are the solutions.

04. Why hot water gets cold and hot in a while during a shower?

Ans. Water temperature fluctuates during that problem. It is called the cold water sandwich problem. Tankless water heaters require time to heat water properly. When you shower just after using an appliance, you face a cold water sandwich problem. It also depends on your valve activity and water flow rate.


Though tankless water heater goes cold after a few minutes, its demand is high. Because of some easy solutions tanks, fewer water heaters are preferred by many consumers. People can fix the cold water problem and get hot water. It plays a significant role in our day-to-day life.

Besides, people like to use the latest technology like an electronic tankless water heater. It lasts longer and even does not need extra space or ventilation space. By taking some simple steps described above, you can enjoy life with hot water. Hope this “The tankless water heater goes cold after a few minutes” post helps you.

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