How to insulate valves, filters, etc.
 

I am trying to better insulate my heat buffer, and the heating system's plumbing in general. Adding another layer of foam insulation and stuff like that.

But there are parts which are more difficult to insulate - inline valves, filters, etc., like in the pic below:
https://ecorenovator.org/forum/attac...3&d=1696098941

My idea for this would be to make 2 halves of a box (shell) out of styrofoam to enclose this stretch of plumbing with the accessories, filling in the void with mineral wool. Not sure how good that would be?
These are things I need access to regularly - the magnetic filter 1-2 times per year, the 3-way mixing valve above it once per week during the colder half of the year - so the enclosure cannot be permanent or difficult to remove.

Any better ideas?

I think your idea is ok. Are you insulating to keep heat in the plumbing or to keep cold out? I know it sounds the same but the question is [is there more heat or more cold] ?

Good question!
The water in pipes will have a temperature of 40-70 deg C, while the basement is usually 15 deg c. I don't mind if the basement warms up by 1 or 2 deg, but don't want the water to cool down.

Ok I still think your idea is a good one!