Turn down ratio is the maximum to minimum heat output.Turn down ratio for direct gas fired burners is 25:1, which means that the burner can modulate from 4% to 100% of full fire. Indirect gas turn down ratio is typically 2:1, which limits the heat output from 50% to 100% of full fire. Mukesh Yadav
To turn off the furnace, locate the power switch or breaker connected to the furnace and switch it off. This will shut down the furnace and stop it from running.
afbc has high turn down ratio,burner arrangement is simple,low grade coal can be burnt efficiently,so2 emission can be controlled,
To turn on a furnace without a thermostat, locate the furnace switch on or near the unit. Flip the switch to the "on" position to start the furnace. Keep in mind that without a thermostat, you won't be able to control the temperature or set a programmed schedule for the furnace to operate.
To turn off a Bunsen burner, first close the air hole at the base of the burner by turning the metal collar clockwise until it's fully closed. Then turn the gas knob on the burner clockwise until it stops to shut off the gas supply. Let the burner cool down before handling it.
Thermostat
it is ratio of maximum air to minium air
To turn off the furnace in your home, locate the power switch or breaker for the furnace and switch it off. This will stop the furnace from running and producing heat.
To shut down a coal furnace, follow these steps: 1) Turn off the power supply to the furnace. 2) Close the air intake and exhaust dampers to restrict airflow. 3) Allow the fire to burn down and the furnace to cool before removing any remaining coal or ash. 4) Dispose of the coal ash properly and clean the furnace as needed.
The furnace may turn on when the thermostat is off due to a malfunction in the thermostat or wiring, causing it to send a signal to the furnace to turn on incorrectly. It could also be due to a short circuit or a problem with the furnace itself.
The on button
You take a match, light it up and turn the knob on the side of the burner.