Flo-Chek

porterbruce

My Taco 219 Flo-Chek to prevent gravity flow is stuck in the closed position when the zone is calling for heat so I am not getting any heat in the rooms serviced by that zone. How can get it unstuck? the chrome splined thumb screw on the top can be backed out. I believe this is intended to allow for gravity feed if power goes out and the circulator won't operate. Am I right? How far can I back out that thumbscrew? Will I get a leak if I back it out all the way? Can it be removed and cleaned to allow it to move freely? Do I need to drain that zone in order to work on the Flo-Chek?

EBEBRATT-Ed

Back out the thumb screw carefully. It could break but is unlikely to cause a leak. Yes, you need to isolate and drain that zone to replace the valve... unless in the unlikely case you have valve installed on either side of the flow check

depending on the age you are probably better off replacing the flow check.

Yes, that is how a flow check works

HVACNUT

You can also isolate and take the pressure off that zone.
Purchase the same Taco flo valve, then just swap out the top portion. Make sure to use the new O-ring and check inside for any debris.
The tops are on pretty tight, so you'll need an 18" pipe wrench and a large adjustable crescent.

lchmb

are you sure the zone isnt air bound? Have you tried purging just that zone? Then again, it may feel like it's working but it could be a bad circ...just thinking out loud..

unclejohn

Was thinking the same thing as lchmb. I can't recall ever having a bad flow check.