How to choose the right Solar Water Heater

220 ltr Supreme Solar Vajra Pressurized

why solar water heater?

A solar water heater is a device that uses sunlight to heat water. It enables substantial energy savings, as the sun shining on 1m² of roof saves approximately 2-3 units of electricity a day. Generally speaking, it is possible to heat 50 to 70 % of the water used in the kitchen and the bathroom in this way. Also can be used for washing machine or dishwasher which consumes a lot of hot water also cuts out the electricity used by these appliances to heat the water and shortens the washing cycles. A basic solar water heater costs on average Rs.13,500, including Tax and installation anywhere in Bangalore. To help you with this investment, the Government gives you Solar rebate on your electricity bills every month too.

Minimum Requirements to install a solar water heater

  1. Shadow Free Terrace or open area
  2. The base of Over Head Tank Height should be at least 5 feet from the floor level (please see photo below)  Click image for larger photo.Solar Water Heater Installation Requirements
  3. After Plumbing work is over, water is to be let in only after 10 pm or before 6 am for the first time.   This is because the tubes have to cool down before water is let in, or else tubes will break within seconds because there is no Guarantee for ETC Glass tubes and chargeable.  Hence keep this in mind and inform the plumber also.  Because each tube may cost around Rs.600 each to replace.   
  4. The slope of the collector should always Face towards the south to get the maximum benefit of solar radiation.  If not, a solar water heater may not work.
  5. Space Requirements for solar water are shown below.  Click to enlarge the image. 

How to choose the right Solar Water Heater

How to choose the right Solar Water Heater

How to choose the right Solar Water Heater

How to choose the right Solar Water Heater

How to choose the right Solar Water Heater

How to choose the right Solar Water Heater

supreme solar 220 GL Specification
supreme solar 220 GL Specification

How to choose the right Solar Water Heater How to choose the right Solar Water Heater


How many litres system to select?

50 Litres per person is an approximate thumb rule.  Keeping mind that a solar water heater is installed just above the bathroom floor.

100 Litres Suitable for 2 to 3 persons per day
150 Litres Suitable for 3 to 4 persons per day
200 Litres Suitable for 4 to 5 persons per day
250 Litres Suitable for 5 to 6 persons per day
300 Litres Suitable for 6 to 8 persons per day
500 Litres Suitable for 10 to 14 people per day

In case if there is more than one floor between the bathroom and the terrace, you may have to recalculate the size of the solar tank.  You can call me on 9632417722 I will help you with this.

Example: for 2 elderly persons and a child you can buy a 100-litre solar water heater, that will be enough.

How the solar water heater works

The solar water heater absorbs sunlight by a solar collector passes this hot water to the solar tank. Conversely. The efficiency of the collectors is at its highest at midday, in summer, when the sky is cloudless, and facing south. However, the collectors also work well in other seasons, when the sky is cloudy, for a good part of the day, even if they face east or west. Likewise, the efficiency is best at a gradient of 35° to the horizon, but good results can be achieved with collectors fitted vertically to a façade. When there is insufficient sunlight, the water is preheated and a backup system takes over to bring the water to the required temperature. This system can, therefore, be used to produce hot water at a constant temperature throughout the year without emitting any CO2.

Do solar water heaters work on cloudy days?

Since solar energy systems require sunlight, the bulk of production will take place under sunny conditions only. The output is directly proportional to the amount of infrared sunlight available at any given moment. A system can generate 50-70% of its typical output under bright overcast conditions. When rain or excessive days of cloudy conditions exist, the use of auxiliary backup where conventional energy will be needed.

what are the advantages of a solar water heater?

Energy Cost is entirely free of cost. So, while you are using a solar water heater unit, you won’t need to worry about a hundred dollars of utility bills.

The most amazing thing regarding solar water heating systems is- you will be getting the energy to run your water heater as long as the sun shines. Wondering, what will happen in sudden wet weather or rainy day? FYI, many solar units are capable of providing you energy even when the sun is not shining. So, you won’t have to worry about running short of hot water even on cloudy days.

Save Space requires less installation space compared to the conventional gas or fuel run water heaters. Still, solar water heaters are more frugal in terms of installation space. Moreover, in most cases, the PV or thermal panels are installed on the rooftop.


Solar water heater help the environment?

yes, it Keeps the environment clean and pollution-free, which has become the demand of recent times. A solar water heating system is environment-friendly as it doesn’t burn any fossil fuel when heating water for you. So, you have the chance to contribute to the environment and take part in the go green revolution

Do solar water heater works in winter?

With good insulation, sunlight will be able to heat the water quite well in a solar water heater winter. The heating is caused by the radiation energy of the sun, which can come through the glass and heat enclosures, even if the outside
temperature is well below freezing – providing good insulation can ensure very small heat loss.  Hence hot water is available during winter too.

Does solar water heater work at night?

No, but hot water generated during the daytime gets stored in the solar tank which is insulated.  A good PUFF insulated tank can keep hot water for more than 24 hours regardless of outside weather conditions.

Does a solar water heater save money?

you might be knowing that the government has been encouraging people to go for various renewable energy options. Besides, they are also offering lots of schemes in renewable energy sectors, as well. Apart from that, investing in
a solar water heating unit is- one time, and it doesn’t require many things else a few necessary fittings. Moreover, the price of solar equipment is decreasing with every living day, and many companies are offering more efficient solar equipment at less investment. So, summing up all these, you will surely save some bucks for installation cost comparing to a conventional water heater unit.

can solar water heaters generate electricity?

No. it cannot generate electricity as these are thermal collectors.  only solar photovoltaic panels are used to generate electricity.

how much energy/electricity solar water heater save

A 150-litre capacity solar water heater system is suitable for 3-4 people and can save up to 1500 units of electricity in a year, depending on hot water used. It can also save.

How long do solar hot water systems last?

approximately around 15-20 years depending upon various techniques used to protect the inner tank of the solar water heater system,   a glass-lined coated tank from supreme solar can last well over 25 years and in some parts of the world, it’s in operation for more than 20 years.

What size/Capacity solar hot water do I need?

As a rule of thumb, a relative water-efficient household is looking at a system size of 50 litres per person depending upon how many floors the hot water is coming to your bathroom.   If for example, you installed a solar water heater just above your bathroom terrace floor, then 100 ltrs is enough for 2 to 3 people.  If the solar water heater is above 2 floors then you need 150 ltrs.  Because the waste of water goes higher as the floor level increases.

what are the types of solar water heaters available

1. ETC evacuated tube collector type,

2. FPC Flat panel collector is the major two types.

And there are pressurized and non-pressurized systems available, choose the one depending on the water pressure you require. If you are not sure about this Please give us a call, we will help you.

Evacuated Tube Collectors (ETC)

Evacuated Tube Collector is made of double-layer borosilicate glass tubes evacuated for providing insulation. The outer wall of the inner tube is coated with selective absorbing material. This helps the absorption of solar radiation and transfers the heat to the water which flows through the inner tube.

Flat Plate Collectors (FPC)

The solar radiation is absorbed by Flat Plate Collectors which consist of an insulated outer metallic box covered on the top with a glass sheet. Inside there are blackened metallic absorber (selectively coated) sheets with built-in channels or riser tubes to carry water. The absorber absorbs the solar radiation and transfers the heat to the flowing water

Professional Help:  Cost 500/- per site visit, Book by advance payment along with location map, name and address via WhatsApp with a screenshot of payment made.

  1. Savings on Electricity Bills
  2. Produces very high hot water
  3. Maintenance Free
  4. Easy to use
  5. Available in Copper panel FPC system
  6. Available in Glass Tube ETC System
  7. The inner tank is made of Stainless Steel / Copper depending on models.
  1. Initial Cost is high
  2. During Cyclonic seasons it may not work properly
  3. If ETC System proper care to be taken, as it's fragile in nature.
  4. If FPC System, proper Service need be done regularly, chances are it may get choked up due to scaling.
  5. ETC Types cannot be used for Pressurized water, hence be careful before purchase, and consult the dealer.
Review Overview

Before Buying solar water there are many important things need to be discussed.   Once you make a mistake in selecting the wrong solar water heater for your water conditions, later it cannot be exchanged or ask for a replacement.  Hence Select the right solar water heater after reading this blog, which is well written for people like me who have the only basic knowledge.  Pressurized and Non-pressurized selection is very very important and do not do any mistake in this.  Hence talk to the dealer before you purchase a system.


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