I finished installing my system this past week in early January. Outside temps around 30-35 deg. mid day. The first day of operation the system gave a solar gain to the water in the storage tank up 40 deg. in about 4 hours.
As the sun goes down the pumps shut off and the fluid drains back into the drain back tank, safe from freezing.
In my opinion drainback is the best way to go.
Using distilled water for the solar fluid and no glycol worries. No heat dump worries either.
Alt-e is a great company to work with. Staff is very knowledgeable and friendly.
The delivery was in wood crates and very well protected.
Heavy so have help on hand.
Quality of the collectors, tank, pumps and controller all seem very good.
If you are in the Annapolis area and need any help, feel free to email me (google Annapolis Builder)
Mike K.

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