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Which Type of Water Heater is Best: Instant or Storage Geysers?

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Geysers are essential home appliances are used to heat water. These days if you go to a marketplace in search of a geyser or even look for them online, you will be flooded with choices. But the main decision you will have to take is the kind of geyser you want to buy. Broadly, there are two types of geysers, – Instant Geyser or Storage geyser.

Whether you are getting a new house or planning on remodeling your old one, choosing the type of geyser that would be perfect for you depends on several factors like, the temperature in your city, your budget, space availability and the number of persons in your household.

Imagine standing under a shower of hot water in winter with your head full of lather, and suddenly the water starts turning cold! Well, this can happen if you choose the wrong kind of geyser. So, picking the right one between instant geyser and storage geyser is important.

However, each of them comes with certain advantages and disadvantages. In this article, we will be comparing both the types and discuss their working, features, pros, and cons.

Instant vs Storage

How Does an Instant Geyser Work

All Water heaters use energy (generally electricity or combustible natural gas) and convert it into heat. It then transfers the heat into water, thus making it hot.

The Tankless water heater is the new buzz in India. It was invented decades ago, but it isn’t as popular in India yet. It is a more energy efficient option over the traditional geysers and has the capacity to produce and supply an endless amount of hot water on demand. So, how does a tankless geyser work?

How Does as Instant Geyser

First thing first, all instant water heaters need a certain amount of flow rate to activate its heating unit. Most instant geysers work on a minimum flow rate of 0.5 gallons per minute. However, there are some models available that can work with a flow rate as low as 0.26 GPM.

When you turn on a hot water faucet, cold water enters the tankless geyser through the inlet pipe. Once the system senses enough flow of water, it activates its heating unit, which rapidly heats the heat exchanger as the water runs through it. This heated up water then goes into the outlet pipe, which is connected to the hot water faucet. Once you shut off the tap, an instant geyser will no longer continue to heat water. It will go into a standby mode and will only start operating again if you re-open the faucet.


  • Continuous Supply of Hot Water

In today’s world, people do not have time. To wait for a storage geyser to heat the water can be a major bummer. Instant geysers can give you hot water with a matter of seconds. It will continue to supply hot water as long as you have the faucet on.

  • Less Power Consumption

It is true that the power consumption per minute of an instant geyser is more than the traditional type. But you must consider that it only heats water for the time you have the faucet on, which ultimately saves power.

  • Takes Lesser Space

If you do not have much space to dedicate to a storage type geyser, then the tankless water heater is definitely your thing. These units come in compact sizes and can fit in limited space.

  • Durable

These types of water heaters are very durable. On average, the life of a tankless geyser is around 15 to 20 years. You can add a couple more years to the unit if it is powered by gas.


  • More Initial Cost

An instant geyser has a huge initial cost. It has a lot of advantages, but all good things come at a certain price. So, this might not be the best option for people who have a tight budget.

  • Complex Installation

The installation process of a tankless geyser isn’t the easiest. You will have to make special kind of drills and would need accessories for its installation. If you are switching from storage geyser to instant geyser, the entire process will be lengthier. You will most certainly need the help of a professional, which will add up to its total cost.

  • High Maintenance

No doubt tankless geysers have a longer life expectancy, but for it to function at its best, you will have to maintain it, which includes annual servicing.

  • Requires a Certain Water Flow Rate to Function

Most models function only when the water flow per minute is at least 0.5 gallons. Many work with a flow rate of 0.26 GPM. In case the water flow is lesser, this type of geyser will not heat water.

  • Temperature Sensitive

Instant water geysers are perfect for tropical and temperate climates. But if you reside in one of the colder states in India, where winter is harsh, do know that the instant water heater has its limitations.

  • First: If the water temperature drops below 4 degree Celsius, the flow rate will decrease as the water will tend to freeze. And an instant geyser has trouble working with a low flow rate.
  • Second: To raise the temperature of water to 40 degrees, which is at 15 degrees, this type of geyser will take a minute. And it will require about 2 minutes to heat it to a temperature of 60 degrees. However, in case the temperature of the water is 20 degrees or above, this type of geysers will do its job in a matter of seconds.
  • Third: If the geyser is connected to a number of water outlets, the heat distribution might not be even. The water running through one faucet might get a little colder than the other.

How Does Storage Geyser Work

A storage water geyser has an inlet, by which it draws cold water into the tank. It uses an outlet which is connected to faucets and showers to give out hot water. Very much like instant geysers, it uses either electricity or gas to heat the water in its reservoir.

A storage water heater has enough storage space to reserve hot water that one can use later. It has insulated walls, which does not let the heat to evade. However, the quality of the insulation decides how long the water will remain hot once you have turned the switch the geyser off.

How Does Storage Geyser

It is a known fact to all that storage geysers have a certain capacity, and it takes time for it to heat water. So, if you are planning to buy this kind of water heater, you should consider the number of members in the house. If you are a bachelor or live with your partner, a tank of 20 to 30 gallons will suffice the water requirement for 2people. If you have 3 members in your family, consider going a step ahead and buy a geyser which has the capacity of 40 gallons. A family consisting of more than 4 or 5 members should opt for a storage capacity of 50 gallons.


  • Inexpensive

One of the most influencing factors while buying anything is our budget. Storage geysers are pretty budget-friendly. You can easily spot a decent water heater with good storage capacity at a reasonable price. Though the ones that run on natural gas tend to come at a higher cost, still they are pretty affordable.

  • Can Store Hot Water

Imagine running out of gas, or there is a sudden power-cut in your area while you are in the shower. The storage geyser can still give you a few gallons of water in those scenarios. With this type of water heater, your need for hot water will not always be determined by the availability of power.

  • Easy to Install

Installation is one thing that bothers us after we purchase an appliance. A complex installation process can be a major turn off. The storage water heater is pretty easy to install. You will not have to toil much or incur heavy expenditure for setting this type of geysers up.


  • Requires More Space

Storage geysers require a lot of space. It will take up a considerable bit of space in your bathroom. In case you have a shorter availability of space, settling for a storage water geyser isn’t the best idea.

  • Water Loses Heat Over Time

The purpose of a storage water heater is to store water while keeping it hot. Even though these geysers come with heavily insulated walls, the water in it tends to lose heat as hours pass. It will have to frequently reheat the water to maintain its temperature.

  • More Utility Cost

As the storage geysers need to heat and then again re-heat water, it tends to consume more energy. Hence the operating cost is more.

  • Limited Hot Water Storage

Storage water geysers have a limited capacity to supply hot water. It takes a considerable amount of time to heat water, and in case you happen to run out of heated water in the middle of taking a shower, you might have to wait for quite a long time to for the fresh supply of hot water to hit the tap or shiver as you continue to take shower in cold water.

Comparison of Features: Instant Geyser vs. Storage Geyser

Instant vs Storage

Other Things to Consider While Purchasing Geyser

In order to choose the best type of geyser for yourself, it is best to pit the features of each type against another to see which one fits your requirements.

1. Space Savings

In the department of space savings, the instant geyser is a clear winner. This type of geysers tends to be way more compact in comparison to the traditional storage geysers. Instant water heaters are tankless. Hence it does not store any water, it accounts for its smaller body, which saves more space.

2. Initial Purchase Cost

Storage geysers cost lesser when one goes to purchase it. Instant geysers can cost thrice as much as a storage geyser, thus requiring more investment.

3. Installation

Installing a storage geyser is far simpler than an instant geyser. It is not only less complicated but also costs less, as it does not require special drillings and fixtures to get the water heater to start functioning.

4. Operating Costs

Tankless water heaters require way lesser energy in comparison to storage geysers. It consumes power only when one turns on a faucet connected to the geyser. Instant water heaters are the better deal if you want to save on your electricity or gas bill.

The storage water heaters, on the other hand, need to constantly re-heat water so as to maintain its temperature. It adds up to its operating cost. In colder states, the heat settings will have to be turned to the maximum to obtain hot water, which requires more power to operate.

5. Lifespan

On average, the lifespan of a storage water heater tends to be between 7 years to 12 years. Instant geysers last between 15 to 20 years, which is almost twice as long as the traditional type. If you intend to buy a storage water heater, you must prepare yourself to replace is more frequently than the instant type.

6. Size of the Geyser

A storage geyser is available in the sizes ranging from 6 liters to 50 liters. The bigger sizes of this type of geysers, can store quite a lot of water to serve a family. The instant geysers are available in the sizes ranging between 1 liter to 10 liters. Even this type of geyser has a decent output rate, but it might fall short if several faucets are opened at the same time.

7. Bacteria Formation

Harmful bacteria can form on the inside the tank of a storage geyser after a few years of use.It can have a negative impact on your health. In addition to it, the bacteria can render a foul odor to the hot water and ruin your bathing experience. With an instant geyser, there is no scope of bacteria formation in the storage tank as it does not have one.

8. Maintenance

The storage water heaters can run easily with full efficiency with minimal to no maintenance. But an instant geyser will need annual maintenance to function at its best. Which makes the storage geyser gain an upper hand in this field!

9. Hot Water Availability

Instant geysers are called so as it can give an endless supply of hot water. This stands especially true if you install a bigger heater.  The storage geysers can run out of the water at any time and it will require you to wait for quite a long time before you get hot water.

10. Heat Loss

Even though storage water heaters have insulated walls, it tends to lose a lot of heat in the process. The geyser makes up for the heat loss by re-heating the water again, which consumes more energy. In the case of instant geysers, the heat loss is negligible, as the water is utilized as soon as it is heated.

11. When to Use

The instant geysers are perfect if you want a constant on-demand hot water supply. However, in cooler regions, this type of water heaters has its own drawbacks. So, if you are from a region which experiences bitter cold in the winter or is very cold throughout the year, it is best you install this type of geysers in washbasins and sinks. And get a storage geyser with a good storing capacity to connect to faucets or showers for bathing.

However, if you hail from a state where the temperature does not drop that much and the water temperature remains at least above 15 degree Celsius (ideally 20 degrees), you can install an instant geyser to function as the central water heating unit.

Different Power Source of Geysers: Gas Powered Geysers & Electric Geysers

The main work of a geyser is to give hot water, be it an instant water heater or a storage one. The heating procedures differ depending on the kind of energy the geyser uses. Now that we have already mentioned ‘gas powered geysers’ and ‘electric geysers’ a few times in the article, let us delve a little into the detail.


Water Heaters Powered by Gas

As the name suggests, gas water heaters use gas burners to heat water. A water heater powered by gas has to be connected to a gas cylinder. Another thing about gas heaters is that these units cost twice as much as an electric heater. But it will save you a lot of bucks in the longer run, as the running cost of an electric heater is way more than gas heaters.

A gas powered geyser has its own shortcomings, even though it is cost-effective in the longer run. You will have to install it in a well-ventilated area so that the soot and additional heat it produces can go out. Also, you must understand that India has a shortage of natural gas; it is not as easily available as electricity. In case you run out of gas at any point, you will have no other choice than to bathe in cold water.

Water Heater Powered by Electricity

Electric water heaters run on electricity and use heating elements to give hot water. Generally, there are two heat elements present in an electric water heater. The heating element present in the upper section does the main job of heating the water. The second element only contributes if the heat knob is at its maximum, to further increase the temperature. However, it is not necessary that all electric heaters will have two heating elements. Some just have one, and it does its job pretty well.

However, if you operate an electric geyser to heat water, you will have to pay heavy electricity bill. Another drawback of this type of hearers is that they last lesser lifespan than the gas powered geysers.

How to Cut Back on Power Consumption while Using Geysers

Saving energy is essential, not only because it will cut back on the operating cost of the geysers, but also the world is running short of enough combustible energy source. With ample of options at our fingertips, the cost of living has skyrocketed.  It is estimated that taking a hot water bath every day can shoot the figures up in the monthly utility bills by 18%!

So, how to make hot baths more economic? Here are 7 ways to cut back on power consumption, even when you use a geyser.

1. Take Shorter Showers or Install a Bath Tub

Showers can have a flow rate as high as 8 gallons of water per minute! To save more energy, you can switch to taking shorter showers under hot water. It is beneficial for your skin as it will retain the natural oils. However, if you want a long relaxing bath, consider installing a bathtub. It will take way lesser water and it is more relaxing.

2. Wash Clothes in Cold Water

Doing laundry requires a lot of water. Using cold water to do the laundry is good both for the fabrics and the utility bill. However, in the cases of stained clothes that require soaking in hot water, make sure to rinse it using cold water to save on power consumption.

3. Turn off the switch of the heater when not in use

Even when the geysers run on a standby mode, it uses some power that adds to your bill. To save electricity or gas, turn the switch off (in case of both storage and instant) when not in use.

If you are using a storage water heater, schedule your bathing time and turn on the geyser sometime prior to that, so that you can get hot water when you stand in the shower. However, if you are reluctant to do so, turn it off at least during the nights.

4.  Keep the Heat Setting of Geyser to Low or Medium

Excessive hot water can damage your skin, and it also increases the operating cost. Keep the heat settings of your geyser to low or medium to slash power consumption by 3% to 5%

5. Install an Instant Geyser

In case you are using a storage water heating unit, consider installing an instant geyser, as they tend to consume lesser energy as it heats only the amount of water that is used.

6. Invest in Low-Flow Showerheads

If you are using a bucket and mug to bath, then it is fine, as bucket will measure out the amount of water you need to use. However, in case you are using a showerhead, invest in low-flow fixtures. It will regulate the amount of water that is drained through the outlet while giving you a satisfactory shower.

7. Fix if there is a Leak

In case your geyser has a leak, fix it immediately. A leak of one drop of water per second can waste around 9 gallons of water a day! It is cancer on your utility bill that needs to be taken care of as soon as you can.

Frequent Asked Questions on Water Geysers?

1.What is a tankless geyser?

Tankless geysers are also called instant geysers. These are water heating units that can produce hot water instantly. It does not require several minutes to heat water which is the norm in the case of traditional type storage geysers.

2.Will I need a separate gas pipe to use for my Instant geyser?

Do use a gas pipe with a minimum diameter of 1/2 inch. This type of geysers requires a higher flame to heat the water and so, a gas line of at least 1/2 inch works better than thinner pipes.

3.Which geyser is better, Instant or Storage?

It depends on preference. If you think about electric consumption, and instant geyser is the better pick. However, if you live in a really chilly region or want to connect your geyser to multiple faucets, storage geysers will work better.

4.What will happen if I forget to switch off my geyser?

In case you have a storage geyser without the feature of auto turn off or auto standby, it can cause serious damage to the geyser. It can even burst and catch fire.
However, if you use an instant geyser, then it will go on a standby mode the moment you close the faucet.

5.Can I install an Instant geyser all by myself?

You can install an instant geyser all by yourself; just go through the manual thoroughly before doing it. But this type of heaters has a little complicated installation process, so it is advisable that you seek the help of a professional.

6.What should I do in case there is an emergency with my water heater?

If your water heater is making strange noises, or you see jolts of fire on the electric board or any other situation that you think might cause a hazard, wear a plastic slipper and take a wooden or a plastic spatula to pull the plug off from socket.  Turn off the switch if you can and call the electrician for help.
NOTE: If you see fire on the socket, do not approach it. Instead, turn off the main switch in your house. Then call the electrician and fire brigade for assistance.


With this we have come to the end of our guide. In our opinion as you can clearly see, storage geysers are time tested. They have their limitations, but they guarantee a certain amount of water. The Instant geyser is definitely an advancement on the storage geyser in terms of luxury, convenience and energy saving. Tankless water heater is perhaps the more upgraded and better option for anyone to buy if the person is not limited by specific weather condition or budget.

Do share and comment below if this guide is helpful! Cheers!

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10 Responses

    1. There are several factors to consider before finalizing the right one. For example, if you want hot water instantly, then go for instant heater. However, if you don’t mind waiting for some time, then storage water heaters are good. But for a 2-member family, we recommend choosing any water with 6 to 10 liters capacity.

  1. knowledge able article. I would like to mention that a new model instant tap water geyser is innovative technology , gives you water in 3-5 seconds , anytime you open the tap. Safe to use, less power consumption. Very essential ,special to woman who is undergoing post delivery phase . To keep herself and baby warm, sanitise baby feeding bottles etc. Its cost effective aswell. Hope comment helps someone.

  2. You have not considered power outage. Storage can save hot water for later time (power is not there). Instant units should have power when you want use if not cold water only.

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