My ten year old steam boiler (with a water feeder) does not have a backflow protector, which is required by code ("The potable supply to the boiler shall be equipped with a backflow preventer with an intermediate atmosphere vent complying with ASSE 1012 or CSA B64.3").
1) This was installed by a licensed plumber, paid for "on the books" and had a gas permit, so all should have been done properly. Is it common practice to ignore the backflow requirement, maybe because of the water feeder, or was he just lax? Note: this is in an unincorporated area of Nassau County, NY.
2) I'll soon be replacing the water feeder (because it flooded the boiler), so this is a good time, and time of year, to make any changes to the boiler supply. Or should I not bother adding a backflow preventer, with no plumbing inspections looming?
3) Given that I do put in a backflow preventer, can someone recommend a device? An inexpensive check valve such as https://www.supplyhouse.com/Bluefin-SLCS050-1-2-Sweat-Spring-Loaded-Check-Valve-Lead-Free
does not seem to conform to the specs. Something more expensive does:https://www.supplyhouse.com/Caleffi-573403A-1-2-NPT-Dual-Check-Backflow-Preventer-w-Atmospheric-Vent?gclid=EAIaIQobChMIotWggZ__6QIVDHiGCh15EgU3EAQYAyABEgLFYPD_BwE