Circuit setter on supply?

steamfitter

This morning I walked by a high rise building under construction and peeked in the window and saw hw finned tube radiation with Danfoss TRVs on the supply. Totally normal to me.
What was surprising to me was a brass strainer before it. I've never seen that before but I guess it can prevent debris from affecting the TRV.
However, even more surprising was the circuit setter downstream of the TRV but before the finned tube.
I always thought they belong on the return. Is this something new? Can you balance a system properly with circuit setters on the supply?

hot_rod

Balance valves can be on either S or R. Hydronic coils typically have them on the return so you are adjusting after the friction loss of the coil. On a radiator or fin tube I think either would be satisfactory, opinions may vary

EBEBRATT-Ed

What @hot_rod said

I am sure from your post that this is an "engineered job". They get paid a % of the job so they want to "be sure it will work" so they pile on all the goodies to raise the job price and their %

Hence strainers and anything else shown in engineering textbooks. Even if not needed

hot_rod

it's fairly common to see a Y strainer in an assembly, like these coil hookup kits from B&G.
Some balance valves, like a PIV pressure independent or PICV pressure independent control valve, have small slots or passage ways that need to be kept free for debris like teflon tape, soldier balls pipe shavings, etc.

An example of one of the Caleffi pressure independent balance valve, on a low gpm version, .5 gpm for example, that slot is pretty small.

steamfitter

Thanks you!