Types of Solar Pool Heaters
Solar pool heaters range from small inexpensive systems intended for above ground pools to larger more costly systems designed for sizeable in-ground pools. You will need to match the appropriate solar pool heater for your pool. Several factors will impact your decision on the type of solar pool heater to select. These factors may include:
- Geographic location (climate)
- Type and size of pool
- Roof or ground mounted
- Type of roof
Solar pool heaters are characterized mainly by the type of collector they utilize. Types of pool collector designs include:
(1) Black polypropylene plastic collectors
Black polypropylene plastic collectors are the most common collectors for solar pool heaters. These panels are modular and may be either rigid or have individual pipes running lengthwise. Individual collectors are normally 4’x10′ or 4’x12′. Individual panels are coupled together to achieve the desired surface area.
Advantages: They are very light, chemically inert, and their many individual tubes, risers, maintain high efficiencies. They are durable, can be mounted on racks easily, and are available in a glazed version for windy or colder areas.
Disadvantages: Require numerous attachment points to the surface to which they are mounted, their modular design can limit mounting locations.
(2) Flexible rubber mat
Systems are made up of parallel pipes, called headers, with extruded lengths of tubing in mats stretching between them. Both the length and the width of the mat are adjustable and typically custom-fit for each application. Mats are typically one eighth to one quarter of an inch thick and allow water to pass through them as a sheet to increase the surface area contact between the water in the solar collector.
Advantages: Mats are very flexible and adaptable to roof obstructions, like vent pipes, they require few if any roof penetrations to install, and they have similarly high efficiencies. They also may be less subject to freeze expansion damage because of their greater expandability.
Disadvantages: The mat itself is glued to the roof and can be difficult to remove without damaging either the roof or the solar panel in reroofing situations, and due to its flexibility, it’s very difficult to rack without total support of the complete mat.
(3) Tube-on-sheet panels made of copper or aluminum.
Metal panels consist of copper waterways attached to either copper or aluminum fins. The fins collect the solar radiation and conduct it into the waterways.
Advantages: They are rigid and can be easily racked. Glazed versions of these panels work very well in windy or colder areas.
Disadvantages: They require more surface area than other systems, because of lower efficiency, and are usually warranted by the installer rather than the manufacturer.
Low-density polyethylene irrigation tubing is coiled in a disk design (see picture below). Tubing contains special additives to provide protection from UV damage. A common size is 6 ½ feet in diameter.
Advantages: Easier to mount on the roof, less attachment points, less expensive.
Disadvantages: tend to have a lot more flow resistance since all the water has to go through the whole spiral, where conventional panels have a header pipe on each end and only some of the water goes through each finger.
Solar collectors can also be grouped into glazed or unglazed referring to the presence of a translucent cover to enclose the tubes/tubing. For a discussion of glazed vs unglazed collectors follow this link. Solar pool heaters can also be categorized as do it your self or professionally installed systems. Here are some examples of do it your self systems:
The three largest manufactures of solar pool heaters are: