Heating, Ventilation, and Air Conditioning (HVAC ) Electrical Practice Test

If the fuse in L2 is blown, what will continue to operate?

1. The compressor

2. The condenser fan

3. The blower motor

4. The crank case heater

The correct answer is: The blower motor

In HVAC systems, the function of the fuses is to protect various components by interrupting the electrical supply when there is an overload or short circuit. Fuses are often designated for specific components, and in a system with fuses for different lines, it is possible for one line to be affected without impacting others. If the fuse in L2 is blown, the components that receive power from that particular line will stop working. However, if the blower motor is connected to a different line (such as L1), it will continue to operate since it is not reliant on the blown fuse in L2. The blower motor is typically responsible for circulating air throughout the system and may operate independently from other components, such as the compressor, condenser fan, and crankcase heater, which might be affected by the failure of L2. This shows that the functionality of one component can remain unaffected while another faces disruption due to a blown fuse, allowing for certain parts of the HVAC system, like the blower motor, to still function even when there is an operational failure elsewhere in the system.