There is no universal replacement schedule
Coil and pod life varies with the device, liquid, usage pattern and manufacturer design. Use the manufacturer's guidance as the starting point rather than relying on a fixed number of days.
Persistent burnt or muted flavour is a warning sign
If performance changes noticeably and does not improve after following the device instructions, inspect the pod or coil. A worn heating element can produce poor or unpleasant flavour and may need replacement.
Check for leaks or visible damage
Inspect the pod, seals and contacts for damage or unexpected leakage. Clean only as recommended by the manufacturer and replace damaged components rather than continuing to use them.
Make sure the replacement is compatible
Before fitting a new coil or pod, confirm the exact model and resistance specified for your device. Similar-looking replacement parts are not necessarily interchangeable.