What Is The Difference Between Pressurized And Unpressurized Solar Water Tanks?

By Author: Latitude51 Solar
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What are Solar Water Tanks?

Solar hot water tanks are the most significant part of solar water heating systems. Their variable size and type are largely not considered or not properly understood by all solar system users for which some of them are even prevented from getting more effectively working solar systems.

Many solar heating systems often come with a small insulated box attached to the side of its built-in residential hot water tank. It is a great design idea, partly because many users don’t often have space for installing larger water tanks in their homes or mechanical section which again saves them from buying another bigger solar water tank.

Though is true, but indicates that the solar heating system will have less heat to store during the bright sunny days.

The solar water tanks serve like a battery used for storing electricity. They usually store thermal heat in hot water. There are two kinds of hot water tanks, Pressurized and Un-pressurized to fulfill the hot water needs of users with RE (Renewable Energy) source. There is another way for solar system users to keep solar ...
... heat. They can directly connect the solar collectors to an in-floor heating system. It will work better in some conditions.

Pressurized solar tanks

These solar water tanks are standard 80 gallon tanks used in the home or office. They are heavy in weight (200lbs) and designed to keep pressurized water supplied to your home through the main city water supply. Some of the pressurized tanks can be purchased with no internal coils to finally get installed with the user preferred heat exchanger, bringing down its price. They will be fit for small size SWHs designed with 1-2 thirty tube collectors. Though these tanks cost less at the time of purchase but cause the users to spend more money and time for adding the external parts like heat exchanger to it.

Buyers can also purchase 120 gallon solar water tanks which weigh more than 300 lbs and are very difficult to move in the home.

When it comes to price and performance of these pressurized tanks, buyers will have to consider a few things:

The length and diameter of the heat exchanger. The better quality, longer and thicker heat exchangers will make the tanks cost more, but help transfer the heat more efficiently.

The heat exchangers should be stainless steel rather than plain steel which will rust and fail too early.

Un-pressurized Solar Water Tanks

These are huge and well insulated water tanks made in custom sizes to match residential and commercial applications. They have oversized coils fitted in them and are made large in size so that multiple sets of solar collectors can be put in them and the domestic hot water system or underfloor heating system line can run through them properly for pre-heating.

The internal coil of un-pressurized solar tanks is connected directly from the main water supply or well to feed automatically into a more conventional water heater. The incoming flow of water gets pre-heated or heated, before getting into the water heating system which fires only when the pre-heated water from the unpressurized water storage tank is found to be insufficient. Though they are expensive but cost less than multiple number of pressurized tanks connected together.

When you are out to buy a solar tanks, you should look upon all the above facts and come up with the right choice. There is no point purchasing your tank without considering all the intricacies as they might reduce the functional ability of your solar water heating system.