New unit leak after first service traced to drain pan not reseated

What we found

A leak that starts right after servicing, on a unit that was previously dry, points to the service visit itself. The drain pan and its seating are the first check.

• Water dripping from the front edge of the indoor unit, not from the drain pipe.
• Drain pipe was clear and flowing when tested.
• Drain pan was slightly shifted and not seated flush against the evaporator coil housing.
• A visible gap between the pan edge and the coil housing allowed condensate to drip past.

The drain pan had been displaced during servicing and was not reseated flush against the evaporator coil housing. Condensate forming on the coil dripped through the gap between the pan and the housing, bypassing the drain path entirely.

What we did

The unit is not defective. The drain pan was displaced during the previous service and needs to be reseated flush against the coil housing. Once aligned, condensate will flow into the pan and out through the drain pipe as designed. No parts and no warranty claim are needed.

After the drain pan was realigned and seated properly, the dripping stopped. The unit ran through a full cooling cycle with no water escaping the drain path.

What we learned

Why post-service leaks on new units are often a reassembly issue.

• A new unit leaking only after its first service — when it was fine before — points strongly to reassembly. A manufacturing defect would have shown up earlier.
• Checking drain pan alignment is a visual and physical check that takes only a short time. It avoids unnecessary warranty claims or part replacements.
• During servicing, the drain pan is removed to access and clean the evaporator coil. If the pan is not reseated flush against the housing, condensate rolls off the coil and misses the pan entirely.