Differences between glazed and unglazed collectors

Solar collector systems are made of different materials. Which collector you will need depends on the climate you are living in and what you tend to use it for. They are usually classified into glazed and unglazed collectors.

Unglazed collectors

Unglazed collectors do not have any glass covering or you can call it glazing. Generally, they are made of heavy-duty rubber or plastic treated with an ultraviolet (UV) light inhibitor to extend the life of the system.

Due to the cheaper parts and the easy design, these unglazed collectors are less expensive than glazed collectors. Unglazed collectors are also used for indoor pools in colder climates because then the water will go back to the pool when not used. Even if you need to shut off the system for a while during colder weather unglazed collectors are more cost efficient than installing more expensive glazed collectors.

Many people think they need expensive glass covers and that unglazed covers don't work at all. This can't be farther from the truth. Not only do unglazed covers work well enough, but they are also more cost-effective for pools in the outside air.

Usually, the heat from the pool is lost from the surface of the water through evaporation, convection, and direct conduction. Hence, if the temperature of the surrounding air is much lower than the temperature of the water a lot of heat will get lost. Thus the water temperature can be maintained by keeping the air temperature comfortable.

The efficiency of unglazed collectors is almost the same as that of glazed collectors, possibly better.

Glazed collector systems

A glazed collector is made from copper tubing on an aluminum plate and it has an iron tempered glass covering, which is the reason they usually are more expensive. In colder periods glazed collectors with heat exchangers transfer fluids enabling them to absorb sunlight a lot more effectively than unglazed collectors. They can be used throughout the whole year and in many different climates.

Both unglazed and glazed collector systems must have freeze protection if they are used under colder conditions.