Why Does My Tankless Water Heater Take Long To Heat Up? (Explained)

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Your tankless water heater might take long to heat up because of the distance the hot water travels from the heater to the open water outlet.

Electric boiler

Why Your Tankless Water Heater Takes Long To Heat Up

Tankless water heaters do not have a storage unit to keep gallons of hot water for an extended period. They use burners and heating elements that quickly heat up the water.

The water then passes through pipes and out of an outlet such as a showerhead.

The outlet will release water at your preferred temperature, and once you are done and switch off the outlet, the how water line is stopped, and the water cools down. Once the water pathway cools, it will need more heating time when you switch on your outlet for hot water again.

Water will take longer to heat up because of the distance the water has to travel from the heater, up the pipes, and to your outlet.

The longer the water has to travel, the more time it will take for it to heat up or dispense the cold water before the heated water can pass through. The delay can last for a few seconds or a few minutes.

While regular tanks can reserve hot water, tankless water heaters cannot, hence the long hot water delivery time. Tankless water heaters can supply you with a constant flow of hot water.

Unfortunately, since the water is heated on demand, it gets cold once you switch on your water outlet.

When you switch on the outlet again, it may release a surge of cold water before the hot water flows again. In other scenarios, the outlet may release a surge of hot water, followed by cold water and hot water again.

This ‘cold-water sandwich’ happens because of the lack of hot water reserves in tankless heaters, so cold water overlaps with the heating water.

Tankless water heaters also use wired technology, so short circuits are a common fold among them. When this happens, the heat sensors stop working, and so will your water heater. The wiring faults may also result in a delayed heating time.

How Does A Tankless Water Heater Work?

Tankless water heaters only generate water when necessary. Unlike traditional water heaters, there will not be a reserve of hot water, especially when it is not needed.

When there is a demand for hot water, you turn on the heater and begin the heating process.

The tankless water heaters have electric units or gas-fired burners that activate when you turn on the heater or open a hot water faucet.

As the water flows up the pipes to the outlet, it is heated along the way at adjustable temperatures and for the desired period of time when the heating system is on.

How Do I Make My Tankless Water Heater Heat Faster?

There are ways you can shorten the waiting time when you use your tankless water heater.

Use A Recirculation System

A recirculation system creates a loop between your heater and outlet and ensures unused hot water does not stay on the pipes.

A thermostat will detect the water cooling down, and the water will begin to reheat again. When you switch on the outlet, the water that comes out is hot instead of how it would be had there not been recirculation.

One con of recirculation systems is that they consume more energy and might not be compatible with all tankless heaters. They are, however, a sure way of heating your water faster and for longer.

Point-Of-Use Water Heaters

These are also known as secondary water heaters and are small units installed below your primary water outlets like a shower or sink.

The point-of-use heater will heat any cold water in the pipes, so it will boost your central tankless water heater’s hot water supply.

Demand Hot Water Systems

Demand hot water systems use a pump connected to your water supply and carry hot water from your tankless water heater to the outlets. It pushes cold water away from the pipes and into a cold line so you will get hot water faster.

You can fit them anywhere in your home, and they save time, water as well as energy.

tankless water heater 2

Benefits of Tankless Hot Water Heaters

Tankless water heaters are a modernized version of water-haeting systems that are gaining popularity and for good reasons.

They are energy-efficient

Compared to the traditional water heaters, they save energy. You do not need to keep gallons of water hot for a long time. You only need to heat water when you need it, a period at a time.

This saves you water and electricity and consequently your money. Some tankless water heaters use natural gases, which are even more energy-efficient.

They are convenient

You only heat up water when you want to, and use the amount that suits you at the time. The hot water supply is endless at any time of the day, as long as you switch on your outlet.

Save on space

Tankless water heaters take up very little space compared to traditional heaters. There are no water storage tanks, so you will save up a lot of room within your home. You can also place them wherever you deem fit and are not forced to keep them in closets or cabinets.

They are long-lasting

Tankless water heaters can last up to 15 years because their general use is minimal compared to traditional heaters.

Traditional heaters carry a lot of water, use up excessive electricity, and generally operate unnecessarily for longer than tankless water heaters.

What To Consider Before Getting A Tankless Water Heater

While tankless water heaters are a good investment, you could consider a couple of facts before choosing them for your home.

1. Consider the frequency of hot water usage in your home. If you have few people in your household or your hot water usage is minimal, then the tankless water heater will work for you.

You will not store hot water unnecessarily with no one utilizing it.

2. Think about the amount of space in your home. If you have a large house with a significant amount of people living there, a tankless water heater may not be ideal.

There is the possibility of high water usage, and since the home is large, there may be storage space for a traditional tank that will hold up gallons of hot water throughout the day.

If you have a small home, then the tankless water heater is ideal because of its size.

3. Tankless water heaters provide an endless supply of hot water but a low flow rate. If you use hot water out of several outlets at a go, for example, during cleaning, tankless water heaters might be a setback.

However, you can combat this shortcoming by installing point-of-use heaters throughout your home and facilitating multiple hot water activities.

Lastly, if you wish to stay in your current residence for a long time, installing a tankless water heater is advisable. It is value for money and will serve you for years without having to replace it.