... safety. ♥ Specification: 50,000/100,000/400,000 kcal/hr ♥ Heating area: 300/600/1200/1800 ♥ Adopt Micro and Nano coating ... of coal. ♥ The air-heater, which applys the latest indirect heating technology , combines the function of combustion and heat exchange which ... (80%-95%),small size and easy installation, low price( half of the price of the heating system of 1 ton boiler) MBQ ...