Electric gas heater also known as Hybrid heater, works on electricity as well as on gas. Its blower / fan uses very less electricity (Max 30 Watts) and burner uses gas for heat. Combined effect of fan and burner reduces consumption of both electricity and gas. Smaller heaters can even work on UPS and less gas pressure thereby no worries of low gas pressure or failure of electricity. These are available for Sui Gas (Natural Gas), LPG and even for Kerosene Oil for those areas where both gases are not available. Advantages of hybrid heaters are:
Energy Efficient about 90% of the energy content of the gas is transformed into heat.
Provide Instant Heat, more than other heaters. They come with a capacity of up to 25 MJ/h (mega joules per hour). That’s equivalent to more than 6kW of electric heating the same as you would get from three 2kW electric heaters.

Cheaper to run than portable electric heaters, even though they are expensive to buy.
Safe: They are equipped with safety feature such as once gas supply is off they switch off and don’t turn on even if gas supply is restored hence no danger of suffocation of room inmates and accidentally blast due to combination of gas leaked any spark. During winter, combustible heaters cause many deaths due to suffocation and burn cases in Pakistan. All the gas appliances must be switched off before going to sleep. However, these hybrid heater are very safe as they provide many safety features.
Your Goal is to design a hybrid heater with additional features. Here are your design requirements:
1. Use button to ON and OFF heater.
2. Use push buttons to adjust temperature value. (one for increase and one to
decrease)
3. Maintain the blower speed to achieve the desired temperature.
4. Use gas solenoid valve to control gas availability. If gas is not available, turn
OFF the heater.
5. In case of gas leakage, buzzer the alarm with 100Hz signal.
6. In case of load shedding of gas and electricity, use small battery only for
turning OFF the gas solenoid valve and heater.
7. Check battery if it drained, then charge it. [Keep in mind the battery charge
and discharge cycles. in case of faulty battery, display it to customer and
beep the buzzer with 80Hz].
8. Display gas availability on LCD.
9. Display temperature on LCD.
10. Use humidity sensor, and display its value on LCD
11. Report should be clearly written and it must include all calculations,
working procedures, discuss results and conclusion.
NOTE:
• Draw schematic diagram for the required tasks and properly mention microcontroller pins connected with sensor(s) and I/O(s).
• You must write sensor(s) and I/O(s) Characteristics and Datasheet Reference.