... pipe series solar collector are always connected with existing heating supply device.2. The selective coating on the inner ... . Hotels, resorts, hospitals and hostels 2. Process industry, boiler feed, laundry and canteens 3. Agricultural sector, hatcheries and ... industry, Boiler feed, Laundry and canteens 5. Agricultural sector, hatcheries, and dairies 6. Swimming pool heating 7. In-process heating 8. ...