Solar controller questions

[mithesaint]

I'm getting ready to purchase the parts for a solar heating system, but there is something that confuses me. I think I'm misunderstanding something.

I'm looking at the Hayward Aquasolar TC system. Per my understanding, there are two temperature sensors. One of the sensors is monitoring the pool water temperature. The other is monitoring the temp inside the solar collector, right? I thought the collectors were supposed to drain when they weren't in use. Is the sensor just checking the air temperature inside the solar collector? Seems like the collectors would heat up very quickly when there is no water in them, but cool quickly once the water starts flowing...Can someone clear this up for me? Thanks.

 

[borjis]

The second sensor measures temp very close/next to your panels, not actually inside them.

The other, you are correct measures water temp in the plumbing.

The panels when not running and hot sun on them do get very warm.

I had solar at my last house and it was fun watching the temp
climb rapidly when engaging them before settling down.

A typical climb would start around 80 degrees then almost peg 100
before settling down to 85-87. (the setup i had, had temp gauges on incoming / outgoing pipes)

Watching solar work and feeling the heat from the jets seems like magic.