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Pressure Reducing Fill Valves

hydronical Member Posts: 24
On my hydronic system, the pressure reducing valve is a Bell & Gossett FB-38TU, which has a fast fill feature. It maintains the static pressure in the system at 12 PSI... When I test the fast fill feature, even by just a little, it takes several seconds to fully close.

Should I (1) continue to use this valve as is, (2) service it, or (3) replace it? If replace is the best answer, what is a good replacement?
--- Bell & Gossett FB-38TU (same as I have now)
--- Caleffi 553 AutoFill, which does not have a a fast fill feature (why was it omitted?)
--- Watts 1156F, which has a fast fill feature, and is least expensive of the three.
--- Other recommendations?


  • icesailor
    icesailor Member Posts: 7,265
    As long as it stops, it won't make any difference.
  • clammy
    clammy Member Posts: 3,086
    the califee doesn t have a fast fill but it has the feature of a dial which you set the pressure you want.When you fast fill you just set it to as higher pressure while purging the system and after your bleed all the air out you re set it to the 12 to 15 psi you need .I started using them a year or two ago and have great luck wth them .Biggest plus is you can fast fill your system and not have to constantly look at your gauge to ensure you don t pop your safety valve ,they have a interanal stop so if your inlet valve is shut you can replace the cartiridge with draining system if you don t have a isolation valve on the outlet of your valve .Great products have used a bunch of there stuff including zone valves , hydro ,dirt mags and of course there auto fill valves .Ps there prv come with a chk valve in the outlet some thing which has become code on boiler installs thats also includes a back flow when i install b & g or watts i have to add a brass check valve ,it s not every inspector but it s defenitky on commerical there looking for it on the residental it s a hi or miss i put them on all ..Peace and good luck clammy
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating
  • hot_rod
    hot_rod Member Posts: 21,790
    The Caleffi 573 fills at 5.2 GPM with 30 psi inlet pressure, much faster than any other. It also has a nice pressure gauge, new for 2015
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream