Frozen Wilkins RK34-375V Backflow Preventer: Poppet Assembly Replacement

Water flowing freely through the vent of a Wilkins RK34-375V after freeze/thaw means the poppet assembly cracked from ice expansion and no longer seats. Good news: you don't need a whole new unit.

Repair

1. Shut off water, relieve pressure.
2. Remove the bonnet/cover (typically 4 bolts).
3. Extract the poppet assembly (spring, stem, rubber seat).
4. Take to irrigation supplier (Ewing, John Deere, local plumbing supply) for exact match.
5. Reinstall, torque bolts evenly, test.

Cost vs. Replace

• Poppet kit: ~$40–$60
• New RK34-375V: ~$250+
• Labor: same either way

Prevention

Next winter, drain the backflow preventer completely using test cocks and ball valves. Leave test cocks open 45°. Insulate with a backflow blanket or enclosure. Freeze damage is 100% preventable.

Don't buy a new unit—rebuild the poppet and winterize properly going forward.