Best use of solar cover

[Mopar4u]

Bought the cheap Doheny blue solar cover. Our pool gets full 100% sun. To get the most heat into the water should i take the cover off during the day and back on at night or leave it on full time when the pool is not in use?

Bubbles facing up or in the water?

 

[cowboycasey]

I leave it on all the time when covered bubbles down

 

[Mdragger88]

The idea behind the cover is to slow down heat loss from evaporation so the longer u have it on the more evaporation it will mitigate.

 

[magiteck]

I initially theorized that it was better to have the cover off when the sun was shining (to maximize solar absorption), and then to cover the pool at night when the sun goes down.

My real experience taught me that wasn’t really the case. The added heat retention with the cover on more than makes up for any reduction in sun getting through the plastic (for me anyway).

Now, I leave the cover on unless the air temperature is warmer than the water temperature (or if we are using the pool, or if the water approaches 90 and I want it to cool down).

When the air is colder, the greater the differential between the water temp and air temp, the more evaporation and the more heat loss. In our Wisconsin climate, having the cover on (minimally) the vast majority of nights makes a huge difference.