There are a few things you can do to obtain the maximum heating for your pool. This assumes that the system is working correctly. (See: Troubleshooting) These are listen in descending order of effectiveness.
- Cover the pool. All solar systems are fighting against nighttime heat loss. A pool cover will minimize this and provide a higher starting point for the next day. Of course, covers are unsightly, a hassle to pull on and off, and need replacing after 2 or 3 years, but they are quite effective. Ideally you should only need one for early and late season use. But some pools, due to shading, wind or other factors may need a cover at other times.
- Increase the number of hours the system runs. Generally speaking you should see good results running the pump about 6 hours per day. However, if you have good sun on the panels before or after the system is currently set, you might try to increase the run time to 8 or even 10 hours. This will cost a little for the extra electricity, but still much cheaper than running a gas heater.
- Make sure you are getting at least 50% of your suction supply from the bottom of the pool. Usually this is done by adjusting a valve at the equipment pad or adjusting the diverter valve under the skimmer basket. The water at the bottom of the pool can be somewhat cooler than the surface; cool water will absorb more heat. Many pools are set to run skimmer suction only, and in effect are re-heating warm water. The results of this may be only slight, but in pools with low issues there may be a greater benefit.
- If the return lines into the pool have adjustable “eyeballs”, direct the flow downward. This will again help to even out the heating.
- In cool weather minimize the use of water features. Large spillways, waterfalls, stream beds, negative edge overflows, fountains, etc. can cool water, especially in windy conditions.