Fix lid seal if a bright red glow is visible around the seal when kiln is operating and/or excessive heat loss can be felt around seal.
- Rub seal high points down with sandpaper until no more than 1/16 of an inch gap is found at any point along seal.
- Check for unevenness in the gap that will cause an excessive heat loss.
- Replace lid if it is excessively cracked or worn or has holes in it. Replace lid.