I'm replacing my boiler. I've decided to go a supply side circulator. I'd like to add a boiler bypass. I'm having trouble identifying throttling valves. I'm not interested in the automatic type. I looked around for globe valves but, nowhere I've stopped seems to carry them (only been to hardware stores so far, not plumbing supply). I know that ball valves aren't desirable for this, for multiple reasons.
Here are a couple of options I've found online, but, the prices seem a bit spicy:
This seems optimal and not available:
Perhaps they are just expensive to manufacture and this is the current state of the market but, I thought I'd check in to see if someone can help me identify a cheaper source, or some product I can request from the plumbing supply and not get floored by the price.
I'm not sure what info is helpful so, I'm including a bunch below.
Thanks for any assistance.
-Boiler: Burnham PV8H3WT-TBWF
-Configured tankless hot water coil with storage tank and circulator pump (not sure I'm describing that right)
-Supply side circulator, single circulator pump, 2 zone valves
-Planned plumbing bits starting at boiler (black pipe to zones, then copper, back to black pipe at return manifold): 1 1/2 to 1 1/4 reducer, LWCO, supply valve (throttling valve), union, Bypass tees in (also want a throttling valve in bypass), Tee with purge at top, ball valve (full port) 18" run, air scoop (below air scoop is tee with pressure reducing valve, check valve, shut off valve to water supply, and below tee, expansion tank) circulator pump, 12" run, flo-chek valve, manifold to zones, zones plumbed 3/4", zone valve, balancing valve (throttling valve needed here), baseboard radiators, shut off valve, return manifold, flo-chek valve, tee to boiler bypass, union, reducer, return to rear of boiler.