When to Replace a Coil Instead of Recoating It
Key facts
| Sign | Recoat | Replace |
|---|---|---|
| White deposits, fins firm | Yes | — |
| Pitted fin edges, fins firm | Yes, expect shorter life | — |
| Fins loose or flaking | — | Yes |
| Corrosion leaks | — | Yes |
| Capacity not recovered by cleaning | — | Yes |
Check the fins first
Press gently on the fins at several places across the face. If they move on the tubes or crumble, the fin-to-tube contact is gone, and no coating will bring back the lost heat transfer.
Check the tubes and joints
Look at return bends, brazed joints and headers. Heavy corrosion there usually precedes leaks, and leaks from corrosion tend to recur.
Compare the costs
Recoating costs cleaning, coating and downtime, and buys time on a coil that is still sound. Replacement costs more but resets the coil’s life — and the new coil can be coated before installation.
What this means for your project
Send photos of the coil faces, fins and joints. If replacement is the better choice, the new coils can be coated before they ship.
