Hot air generator lining: what to check before and after startup

Hot air generators supply heat to dryers in textile, food, chemical and many other plants. Whether the unit is new or freshly relined, the first startup decides how long the lining will last.

Before startup

• Lining finished as per drawing, with joints and expansion gaps checked
• Burner block or grate area properly seated
• Doors, peep holes and inspection openings sealed
• Insulation and casing complete, with no gaps
• Thermocouples in place for dry-out monitoring

During the first heat-up

• Follow the dry-out schedule from your refractory supplier
• Raise temperature slowly, with the specified holding periods
• Watch for steam from the casing; it should reduce steadily
• Do not stop and restart without guidance
• Record temperatures on a dry-out chart

After the first week

• Check casing temperatures for hot spots
• Inspect doors and openings for gas leakage
• Look for cracks around the burner or firing area
• Compare flue gas temperature and fuel use against design

Long-term care

Regular cleaning of the heat exchanger, steady firing practice and an inspection at every stop keep a HAG efficient for years.

JISPL builds hot air generators in-house and relines existing units, with dry-out supervision on request.