question on taco flow check #220 / 1"

oreo123

Low heat issue. Two zone boiler. Boiler cycles up to high limit fine.

One zone is domestic hot water into super store and that zone is fine.

Second zone is heat - a monoflow loop. Bled convectors and no air found. Pump is on supply side. Return side was not that hot. Had a 007 new pump and swapped that in. Same issue so its got to be the flow check.

Taco flow check is around 15 years old. Backed the top all the way up and getting decent flow. Its a # 220 which is 1 inch. The plan is to just change the guts by spinning off the top. If the store does not have the correct part tomorrow does anyone know if the inside parts are interchangeable from the @218 which is 3/4 ? And what about #221 which is 1 1/4 ?

Thanks....

HVACNUT

Raising the weight worked?
If so, get the 1" Flo valve and yes, just swap out the top. Go in with a rag and make sure the brass seat is clean and smooth.