Bypass between supply and return headers / manifolds?

woobagooba

I've got a 3/4" copper connection between my supply and return labeled "bypass". It includes a ball valve with the handle at 45 (versus the direction of flow). Hoping someone can explain its purpose. Thanks

hot_rod

got a pic? Some manifolds have pressure bypass valves added on or built in. Sounds like the valve you have is a way to isolate the branches.

woobagooba

Here is a pic of the return manifold (supply "manifold is tangle of CI and copper in the ceiling). The bypass valve in question is on the far left end of the return manifold.

STEVEusaPA

It's the cheap and horrible way to do boiler protection.

woobagooba

Please explain

hot_rod

what type of boiler?
Why a bucket under the BFD vent pipe?

woobagooba

Its me again

https://forum.heatinghelp.com/discussion/170834/buderus-gb142-multiple-corrosion-issues#latest

Pay no attention to the bucket. That was wanna-be-HVAC-guy draining the failing ST120 to pull what I expect to see is a decimated anode.

Steve Minnich

Looks like a modcon? Nothing to protect.

HVACNUT

It's a Buderus GB-142.
If its piped directly back to the return without anything else inline, shut off the valve, remove the handle and zip tie it near the valve. A bypass is counter productive on a mod con.
And whether it was supposed to be a boiler bypass or system bypass, its piped wrong either way.

woobagooba

@HVACNUT Roger that and thank you