Solar water heaters are manufactured as pressure and non-pressure models. Pressure model (also called high pressure solar heaters) means, water in the tank are under high pressure, it's equal to the pressure of tap water. Non pressure model (also called low pressure solar heaters) means, water in the tank is under low pressure, and is equal to the gravity of the water. There are some fundamental differences which you should be aware of before deciding which one works best for you and which one you should install.
Compact Low Pressure Solar Water Heater
The low-pressure system is combined with vacuum glass tube collector, an insulated storage tank and stand frame. The evacuated glass tubes are filled with water and exposed to sun, thus heating up the water in the glass tubes.
As the specific gravity of cold water is heavier than hot water, the hot water in the glass tubes starts rising in the insulated water tank, and the cold water in the insulated water tank sinks into the glass tubes. As this cycle is repeated, water in the solar water heater gets heated. This process is known as thermosiphon and is based on natural convection..
Integrated High Pressure Solar Water Heater
Typically characterized by a heat pipe connected indirectly to a tank. There is no direct connection between the working fluid in the copper tubes and the water being heated in the tank
The solar collector absorbs light energy through the AL/N/AL/SS/CU coating, and converts light energy into heat energy, stores heat energy in the insulated water tank through a heat pipe, which relies on the thermosiphon principle for natural circulation heating of the water tank. The tank is enclosed pressurized which provides high pressure hot water.
It doesn’t really get more basic than this, because there are no pumps or other moving parts involved, which means you have less to worry about. In fact, you’re looking at a cut in costs for installation as well, seeing as the complications are minimal.
And this system is 100% solar powered, no electricity required. Therefore, it is the best choice for people who live in places having electricity cut often or no electricity at all.
People Who Will Appreciate Non Pressure System
The first benefit that jumps to mind is the affordability. Given that this particular geyser is so cost effective, it’s a logical economic choice if you have a tight budget. Except in cold regions, It is widely used in Mexico, Mauritius, South Africa, Kenya, Ghana, Mozambique, Morocco, etc
People Who Will Appreciate High Pressure System
This system is especially suitable for high-latitude, cold and low temperature areas. People who live in these areas can buy this system for domestic hot water because the solar heat pipe adopts a phase change heat transfer design, and the hot energy start is fast. When heat pipe stand by under sunshine, the temperature reaches 222 ° C, which can provide high temperature hot water. Moreover, the tank is designed with a pressure-bearing structure, with a test pressure of 0.9Mpa and a working pressure of 0.6Mpa, which can supply pressure hot water to make people more comfortable when taking shower.
Making your home more energy efficient can be done in many ways. Which one of the two will serve you best and save you the most money? But there is no straight answer. Instead, your needs and demands are going to determine which one suits your lifestyle better. Hope this article can help get a better understanding of what you need.