Why won't my home Hvac blower turn on?

check the circuit breakers to make sure one isn't tripped. some furnaces will have an on/off switch inside the cover. on the electric motor that turns the fan should be a reset switch, usually on the end. it will look like a small red button. if it's tripped it will be sticking out a little bit, try to push it in until it clicks and locks in place. also depending on what kind of system you have some won't start the fan if the A/C unit is low on refrigerant or covered in ice.