What should the amps be on a blower motor?

Typically, a standard blower fan needs on average 400 watts of electricity. This means that it needs a 15-20 amp circuit. However, depending on the size of your furnace, the amount of needed power could be 20 amps or more.

Why is my motor drawing too many amps?





Electrical overload or over-current is caused by an excessive current flow within the motor windings, exceeding the design current which the motor is able to carry efficiently and safely. This can be caused by a low supply voltage, resulting in the motor drawing in more current in an attempt to maintain its torque.

What causes higher amp draw?

What Causes a Motor to Draw Higher Amps? Motors require a certain output in watts in order to function, and this is the result of a voltage multiplied by amps. So when voltage falls, resistance scales up in order to supply the difference, and the motor will also draw more current.

How does a motor draw more current?

As more mechanical load is applied, the motor slows, the back emf decreases, and more current is drawn. If sufficient mechanical load is applied, the motor stalls/stops rotating, and therefore there is no back EMF at all, and the current is limited by the supply or by the resistance of the windings.

How do you test a blower motor amp?

Quote from the video:
Quote from Youtube video: And i just closed the damper. And you see the amp draw has dropped. Now opening the damper the amp draws up to where it should be closing the damper. The amp draw has dropped.

What does amp draw mean?





In simple terms, your machine’s amp draw measures how hard your machine must work to run. Think of it like your treadmill’s blood pressure. In the same way your heart works to circulate blood through your body, a treadmill requires electricity to flow through its components.

How do you reduce amps on a motor?

According to Ohms Law (I=E/R or Amps=Volts/Ohms) if the voltage in the circuit remains constant and the resistance is increased, the current should decrease. Try adding resistance to the circuit to lower the current output.

How many amps should a motor draw with no load?

Benefits of Finding Motor No-load current:



Instead of that by calculating no-load current of the 50HP motor (it will be 6 to 10 Amps), you can design low rated starting equipment (i.e starter, cables etc) to start the motor at the maintenance floor itself.

Can low voltage cause high amperage?

If the voltage decreases, the current will increase in roughly the same proportion that the voltage decreases. In other words, a 10% voltage decrease would cause a 10% amperage increase.

What does low amp draw mean?



Low amp draw is fine. Its better. It means the motor’s are using less power than they are allowed to perform the same job. Unless it’s overheating or making weird noises, its fine.

Is a higher amp motor better?

So amps measures or indicates the maximum time a tool can continuously run without exceeding the temperature limits. Amps basically measure how effectively the motor cools itself, not how much power it has. With this in mind, more amps can be good because motors will run longer and won’t heat up as fast.

Can you over AMP a motor?

Answer: No. The motor will draw the current it requires. This current is limited by the resistance of the motor.

What determines amp draw?



Ohm’s law states that the voltage equals the amperage times the resistance, so if you divide the voltage of your power source by the resistance of the load, you will find the amps. For example, if you plug a 40-Ohm dryer into a 220-volt outlet, the appliance will draw 5.5 amps.

How do you check amp draw on a motor?

Quote from the video:
Quote from Youtube video: And then we need to put our meter in the circuit to test amp draw. And how do you do this. Well. You put your black lead to your meter toward.

How do I know if my blower motor is bad?

What Are Signs Your Blower Motor Needs to Be Replaced?

  1. Poor or Airflow from Air Vents. This will be the first and most obvious sign your blower motor has a problem. …
  2. No Airflow At All From Vents. …
  3. Skyrocketing Energy Bills. …
  4. Strange Noises When You Turn on the Heat. …
  5. Overheating Blower / Weird Smells.


Do blower motors get weak?



Similar to other components in an HVAC system, the blower motor will become more vulnerable to mechanical failures as it experiences more wear and tear over time. If your air conditioner is aging and becoming increasingly problematic, there’s a good chance the motor is in trouble.

How do you test a blower motor with a multimeter?

Quote from the video:
Quote from Youtube video: Now you can take your multimeter connect it to one of your jumpers. Here. And the other lead of the multimeter to that jumper make sure they don't touch here now we're ready to test the amperage draw.

How do I change the speed on my AC blower motor?

You can increase or decrease the blower speed by slightly adjusting the pulley on the blower drive motor. To increase blower speed, slightly loosen the setscrew that holds the pulley to the driveshaft. Move or turn the pulley clockwise on the shaft one turn, then tighten setscrew.

How can I make my furnace blower faster?

When increasing the blower speed, loosen the setscrew a little bit. This is the part that holds the pulley to the furnace’s driveshaft. Turn the pulley one rotation clockwise on the shaft. If you want even more speed, do two rotations.

How do I increase the speed of my air conditioner fan?



Quote from the video:
Quote from Youtube video: So you can be normal or your low or your high. So you would just pull this pin connector off if you wanted to lower this down say to take more humidity out of the building. You can run at a lower CFM.