temperature reducing valve

[chuck172]

I generally charge my 500 gallon storage up to about 195*.
I'd like to then reduce my temps down to about 150-160* to supply my zones. My mains are 1 1/4" copper off the storage tank.
What should I use here?

 

[ewdudley]

I generally charge my 500 gallon storage up to about 195*.
I'd like to then reduce my temps down to about 150-160* to supply my zones. My mains are 1 1/4" copper off the storage tank.
What should I use here?

Danfoss and Termovar both make versions of their boiler return protection valves with 160 degF mixing guts. Danfoss, at least, has both 1.25 inch and 1.50 inch FPT housings available.

Might be special order and upwards of $200, but they have nice big Cv's and should be simple and reliable.

An alternative might be primary-secondary with a secondary injection flow from storage, but if the amount of flow on the primary side varies according to the number of zones calling, then the secondary injection would need a fairly expensive variable speed control.

--ewd