Solar water systems use different types of heat exchangers so that a transfer of solar energy to solar collectors is achieved and an air or liquid are used in order to heat water or space. One heat exchanger can be made out of copper, stainless steel, steel, aluminum, cast iron or bronze. In most cases copper is utilized as it is a really good thermal conductor. It will also provide good levels of corrosion resistance. Let us now think about common types of heat exchangers that you can see.
Basically 2 main types of exchangers exist: liquid to liquid or air to liquid. Heat transfer fluid is used by all heat exchangers designed for liquid to liquid solar systems. It basically circulates through solar collectors, absorbs heat and goes through heat exchangers so that heat is transferred towards the water in the storage tank. A number of heat transfer fluids will protect the collectors from freezing.
For a liquid to liquid exchanger to be effective there will be a need to utilize one or 2 good barriers. One heat exchanger built with a one wall system usually has a pipe or tube surrounded by fluid. A double wall exchanger will have 2 fluids and walls between them. Double walled solar water systems are needed so that safety offered is higher. The problem is that their efficiency is not as big when compared to single systems. All air to liquid systems will include the use of air heater collectors. Between the solar collectors and the air distribution systems there will be no need of using heat exchangers. The two exchanger systems stand out as being highly similar besides the fact that one uses air and the other liquid.
Whenever you build a solar water heating heat exchange system there is a need to analyze sizing. If you want everything to be effective size is really important. Whenever thinking about this topic you need to consider the heat exchanger types, the heat transfer fluid characteristics, flow rates and temperatures for inlet and outlet for the fluids used. In most situations the manufacturer will offer you heat exchanger ratings to consult. Read all the specifications in order to make the best possible decisions.