Ceoighe 2 Pack Anti Siphon Valve Repair Kit, Vacuum Breaker Fix Set Compatible with Legend Valve LEG-108-903 T550 T550A, Frost Free Faucet Repair Kit for Outside Faucet Fix

Why I reached for this kit

The anti-siphon vacuum breaker on my frost-free hose bib (Legend Valve T-550) finally gave up—leaking at the bonnet, hissing air, and dribbling every time I turned the spigot on. Replacing the entire faucet is overkill if the stem and body are healthy; the vacuum breaker is a serviceable part and, in most cases, a 10-minute fix. I picked up the Ceoighe vacuum breaker repair kit because it’s billed as compatible with the Legend T-550/T550A, and it comes as a two-pack—useful if you have multiple hose bibs or want a spare on hand.

What you get

Each kit includes:
- Two metal press-on caps
- Two plastic bodies with preinstalled O-rings
- Two pistons (the small internal piece that actually seals), with the pronged end designed to face the valve

Everything is sized for 3/4-inch openings, which matches the common Legend T-550/T550A vacuum breaker.

The cap is metal and feels more substantial than the flimsy plastic caps you see on some budget kits. The body and piston are plastic, which is normal for this part. The O-rings arrived lightly lubricated and intact.

Installation and setup

Swapping the vacuum breaker on a Legend T-550 is straightforward:
1. Turn off water at the supply to the faucet.
2. Pop off the old cap (a flat screwdriver or a small pry bar works) and remove the old body and piston.
3. Clean the valve seat and threads—mineral scale here is the enemy of a good seal.
4. Drop in the new piston with the flat end up and the prongs down toward the valve.
5. Seat the new body with its O-ring against the spout shoulder. Hand-tight pressure is enough; don’t crank on plastic.
6. Press on the metal cap. I seated it with a firm push from the heel of my hand.

On my first faucet (a 6-inch T-550), it took under a minute and sealed immediately—no drips from the cap, no weeping from the spout with the handle closed. On a second faucet (a 10-inch T-550), I did run into an issue I’ll describe below.

Fit and performance

On a healthy T-550, the kit fits as advertised. The cap snaps on positively, the body sits flush, and flow is unaffected. With the faucet off, the atmospheric vent closes as it should; with the faucet on, the breaker seals and you don’t get spray or leakage through the cap. After installation, I cycled the faucet a couple dozen times and checked for telltale dampness at the breaker—none on the first unit.

Backflow protection is passive here: when supply pressure drops, the breaker admits air rather than allowing contaminated water to siphon back. There’s no easy DIY test for true backflow, but functionally, the piston is doing what it should when it closes under pressure and opens to atmosphere when pressure drops. That’s what you want.

A quirk worth noting: piston stability

My second install exposed a design quirk. The piston is free to rotate within the new body. On one faucet, no issues. On the other, after a few uses, the piston had rotated just enough that it didn’t seat concentrically when the faucet opened, and I got a small spray out of the vent holes. Reseating the piston fixed it temporarily, but the symptom returned.

Two workarounds solved it for me:
- Reuse the original body with the new piston and cap. The OEM body on my faucet has a slightly tighter bore that keeps the piston from wandering. With that setup, the leak disappeared for good.
- If your original body is damaged or unusable, align the piston carefully and make sure the body is fully square and seated; a tiny misalignment amplifies the rotation problem. It’s not a guarantee, but it helps.

This isn’t a deal-breaker, and it won’t show up on every faucet, but it’s something to be aware of. If your original body is in good shape, using the new piston and cap with the OEM body is a perfectly valid repair.

Build quality

• Cap: The metal press-on cap is the star of the kit. It feels sturdier than typical plastic versions and snaps on securely. It also pries off cleanly for future service.
• Body: Standard molded plastic with a decent finish. The O-ring groove is clean, and the supplied O-ring seals well. Like all plastic parts in this class, it will not tolerate over-tightening or wrenching.
• Piston: Light plastic with a thin sealing edge. It seals reliably when guided correctly. Because it can rotate, body geometry matters.

I wouldn’t expect the plastic parts to survive abuse or freezing with water trapped behind them—no vacuum breaker will—but under normal use they are up to the job.

Compatibility notes

• This kit is sized and shaped for Legend T-550 and T550A frost-free faucets in the common 3/4-inch vacuum breaker size, regardless of faucet length (4–14 inches). If you’re trying to adapt it to a different brand or a non-AVB spigot, results will vary.
• Check the spout shoulder and seat for dings, scale, or burrs. Even a small nick can compromise the O-ring seal on the body or prevent the piston from sealing perfectly.

Tips for a clean, leak-free install

• Mind piston orientation: flat end up, prongs down toward the valve.
• Lightly clean and de-scale the spout end before assembly; a nylon brush and vinegar do wonders.
• Seat the body squarely. If you see any daylight or uneven gap under the cap, re-seat before pressing the cap home.
• Don’t overtighten. The body isn’t meant to be torqued—hand pressure is enough.
• After installation, run the faucet and watch the vent for a few seconds. A drip-free vent under flow means the piston has seated correctly.

Value

As a two-pack, the cost per faucet is reasonable, especially versus buying an entire new frost-free faucet. If you only need O-rings, this is more than you need; but having a spare piston and cap on hand is nice insurance, and it saves a run to the store mid-season. The cap’s sturdier construction is also a plus compared with bargain kits.

Who this kit is for

• Homeowners with a leaking or failed vacuum breaker on a Legend T-550/T550A who want a quick, inexpensive fix.
• Anyone who prefers a press-on cap over screw-on designs for quicker service.
• People maintaining multiple exterior spigots who’ll use the second kit within a year or two.

If you’re dealing with a different brand of hose bib, or if your faucet’s spout end is dinged up, I’d look for an OEM-specific kit or be prepared to reuse your original body with the new piston.

The bottom line

On my first T-550, the Ceoighe vacuum breaker repair kit was a 60-second, leak-free repair with a sturdier metal cap than the original. On my second, I hit a piston-rotation quirk inside the new body; reusing the original body with the new piston and cap fixed it completely. That dual experience sums up the kit: the parts are well made for the price, the cap is a genuine step up, and installation is easy—but the body’s internal geometry may not play perfectly with every faucet.

Recommendation: I recommend this kit for Legend T-550/T550A owners as a cost-effective, quick repair—especially if your original body is still serviceable. Expect an easy install in most cases and be ready to reuse the OEM body if you encounter piston misalignment. For the price and convenience of a two-pack, it’s a practical addition to a home maintenance kit.