Downward deepend of collector

Simply Rad

I think that is the name Caleffi calls the capped end on the down sloped solar collector manifold.   In a drain back situation what do you do with the potential freeze area.

Jeffrey

Simply Rad

I meant downward deadend

Opps



Jeffrey

Simply Rad

I meant downward deadend

Opps



Jeffrey

Kevin_in_Denver_2

Plug

You can plug it with a silicone test plug...

Simply Rad

Silicone test plug

Kevin

Do you have an example of the the product. How do you seal the plug..with RTV sealant?  Is the silicone able to handle the high temps?



Just how my brain works.

Thanks



Jeffrey 

hot_rod

I built one

by using a short piece of 3/4 copper with a cap on it. The cap was a snug fit inside the 1" copper header. I shoved it in to the first riser and soldered it. Then capped the end of the collector header. With a good joint on the inner plug, you could leave the header pipe cap off as a safety, anti freeze feature. I suppose the inner plug could be inserted with red Hi-temp RTV. Make the nipple long enough to seat against the cap on the header.



Dale at Radiant Engineering invented a plug like a mini thermos bottle plug. Insert it inside and expand it. I don't know if he plans on marketing it?



Depending on how steep you pitch the collector, I'm not sure all that much fluid would lie in there between the end and first riser? I don't hear of the DB installers addressing this??



A nice drainback specific collector could solve this "deadend" dilemma



hr

Kevin_in_Denver_2

Rubber expansion plug

http://www.plumbingsupply.com/testing.html



this link shows a photo of an expansion plug. I had to track down silicone "bar stock" and drill a hole in it for the bolt.



Silicone is the only elastomer that can handle the high temps at stagnation (which you can't avoid with controls or anything else.)