Day vs Night

[roman009]

I read somewhere on the forum that it's better to run the filter during sunlight hours for a SWG. I was under the impression that it's generally better to run it at night - sunlight doesnt break down the FC and you can achieve sanitation in fewer hours of pump operation.

Which do you prefer and why?

 

[woodyp]

You need to be putting it (FC) in there while it is largely being consumed. Or you can break up your run times with a timer.

 

[jblizzle]

It makes very little difference. Day preferred, but night is fine if power is cheaper.

 

[roman009]

But why is day preferred?

 

[elwood58]

Day is usually preferred as you are generating additional chlorine when chlorine consumption is at its peak. SWG pools use a lower ppm of chlorine and a higher CYA. If you ever get behind on chlorine production, and an algae problem develops, it takes a bunch of chlorine to get to shock level and clear the algae. As mentioned, you can also split runtime between dark and sunlight hours. My folks run their SWG pool from the wee hours until just before noon, which is when the rates go up. They have their SWG set so that when they measure chlorine at sunset, they never drop below the minimum recommended level.

We tend to run during the day, especially when using the HeatPump to warm the pool. When we get to the point where we need to run the HeatPump in chiller mode, we will start the pump in the wee hours to take advantage of cooler temps for chilling.

 

[jblizzle]

With the sun on the pool and no circulation, you could get localized places where the FC drops too low. And as Elwood stated, with a SWG, adding the FC during the day beneficial.

Again, day is only slight more desirable, certainly not required.