[solarhotairpanels]

Hi Mike,

Thanks for your comments.
My air vent is a manual vent.. ball valve just cracked open.
I tested the sytem both ways.. with and without the vent and the return water actually DUMPS right back into my drainback tank with the air vent just cracked open.. as in barely open.

After I installed the vacum release valve I did not need to leave the air vent open any longer because all water 'was' draining right back just not as fast as if I left the air vent cracked open.. so I decided, being it's winter time I cracked the air vent open again just because the water literally dumps right back in quickly.

I feel much secure that nothing is going to freeze in my pipes but well appreicate your input and technical knowledge for sure.

So far so good on the insluation.
Nothing melted all summer long which I was surprised a bit.

Using the foam self stick stuff but wrapped the pipe exiting the collector with fiberglass wrap insulation prior to putting the foam over that.

The fiberglass is protecting the foam for the first 5 ft leaving the collector where the water is the hottest.

I almost forgot to do that when I was installed the foam stuff.. then remembered last minute.

so again..
so far so good..

Just wish I had about 4 more evac tube collectors during winter cuz it's hard to bring the water temps up very much with so little sun during later Nov thru end of Jan.