Fridge Amp Guide: Don't Get Shocked! [Calculations]
Understanding the electrical demands of appliances is crucial for household safety, and a refrigerator represents a significant power consumer. The amperage a fridge draws directly impacts circuit breaker selection and overall electrical load management. Therefore, determining how much amp required for fridge demands careful consideration of factors like appliance energy efficiency ratings, typically assessed through the Energy Star program. Calculating the appropriate amperage ensures a safe and efficient home electrical system.
Image taken from the YouTube channel Λsk Λbout Horizons , from the video titled How many watts does it take to run a refrigerator? .
Fridge Amp Guide: Don't Get Shocked! [Calculations]
This guide is designed to help you understand how much amperage your refrigerator requires. Determining the correct amperage ensures safe and efficient operation, preventing electrical issues and potential hazards. Understanding how much amp required for fridge is crucial for homeowners, renters, and anyone looking to install or upgrade their kitchen appliances.
Understanding Amperage and Your Fridge
Amperage, often shortened to "amps," is a measure of electrical current. Your refrigerator, like any electrical appliance, draws a certain amount of current to operate. Knowing this amount is vital for:
- Choosing the correct circuit breaker size.
- Avoiding overloaded circuits.
- Understanding your energy consumption.
Finding the Amperage Information
The best place to find the amperage information for your refrigerator is on the appliance itself.
Where to Look
- Nameplate: Typically located on the back, side, or inside the refrigerator door. This plate provides crucial electrical information.
- Owner's Manual: The manual should contain the refrigerator's specifications, including the running amperage and starting amperage.
Information to Look For
- Amps (A): This is the running amperage, the current the refrigerator draws during normal operation.
- Starting Amps: This is a higher amperage the refrigerator draws briefly when the compressor starts. It’s crucial for determining circuit breaker size.
- Voltage (V): This is the electrical potential the refrigerator is designed to operate on (usually 110-120V in North America).
- Watts (W): While not directly amperage, you can calculate amperage from wattage and voltage (Amps = Watts / Volts).
Calculating Amperage Needs
If you only have the wattage and voltage information, you can calculate the amperage.
The Formula
The basic formula for calculating amperage is:
Amps (A) = Watts (W) / Volts (V)
Example Calculation
Let’s say your refrigerator is rated at 500 watts and operates on 120 volts.
Amps = 500 Watts / 120 Volts = 4.17 Amps
Therefore, the running amperage of the refrigerator is approximately 4.17 amps.
Factoring in Starting Amps
Refrigerators require a significantly higher amperage for a very short time when the compressor starts. This is called the "starting amperage" or "locked rotor amperage (LRA)".
Importance of Starting Amps
- Circuit Breaker Tripping: If the circuit breaker is not rated high enough to handle the starting amperage, it will trip, cutting off power to the refrigerator.
- Appliance Damage: Repeated tripping of the breaker can potentially damage the refrigerator's compressor over time.
How to Determine Starting Amps
- Nameplate: Ideally, the starting amperage will be listed on the nameplate. It might be labeled as "Starting Amps," "LRA," or "Locked Rotor Amps."
- Estimation: If the starting amps are not listed, a general rule of thumb is to multiply the running amps by 3 to 5. However, checking the user manual and specific product information is always recommended.
Example
Using our previous example with a running amperage of 4.17 amps:
- Estimated Starting Amps (using a multiplier of 4): 4.17 amps * 4 = 16.68 amps.
Choosing the Correct Circuit Breaker
Selecting the appropriate circuit breaker is essential for safety and preventing nuisance tripping.
General Guidelines
- 15-Amp Circuit: A 15-amp circuit is often sufficient for smaller refrigerators with low running and starting amps.
- 20-Amp Circuit: A 20-amp circuit is recommended for larger refrigerators, especially those with ice makers or other power-hungry features.
Calculation and Recommendation
- Determine Total Amps: Add the running amperage of all other appliances sharing the circuit (if any).
- Factor in Starting Amps: Add the refrigerator's starting amperage to the running amperage of other devices sharing the same circuit (if applicable). If it's the only thing on the circuit, make sure the breaker is large enough to handle the fridge’s starting amperage.
- Choose Breaker Size: Select a circuit breaker with a rating slightly higher than the total amperage calculated, but without exceeding the wire's capacity. Remember that it is recommended not to exceed 80% of the breaker's capacity for continuous loads such as refrigerators.
Example
Let's say our 4.17 amp refrigerator (with an estimated 16.68 starting amp) is on a circuit without any other appliances:
- Based on the running amps alone, a 15-amp circuit could theoretically handle it, because 4.17 is far less than 15.
- However, because the starting amperage is estimated at 16.68 amps, the 15-amp circuit breaker would likely trip when the compressor starts.
- To prevent this, a 20-amp circuit breaker would be the more suitable choice.
If the fridge shared a circuit with a device with a constant load of 2 amps, one would still need to take into consideration whether the starting amps of the fridge + the constant load of the other device exceeded 80% of the breaker rating.
Important Note: Consult a qualified electrician for any electrical work or if you are unsure about the correct circuit breaker size. Working with electricity can be dangerous.
Video: Fridge Amp Guide: Don't Get Shocked! [Calculations]
Fridge Amp Guide: FAQs
Here are some frequently asked questions regarding calculating your refrigerator's amp draw and electrical safety.
What's the quickest way to find out how much amp required for fridge?
The easiest method is to locate the refrigerator's nameplate. This is usually a sticker on the back or inside the refrigerator. It will list the amperage (amps) or wattage (watts). If it lists watts, divide that number by your voltage (usually 120V in the US) to get the amps.
My fridge nameplate only lists watts. How do I calculate the amps?
Simply divide the wattage by your voltage. For example, if your fridge is rated at 500 watts and your voltage is 120 volts, the amperage is 500 / 120 = 4.17 amps. Remember to consider startup amperage, which can be higher.
Why is it important to know how much amp required for fridge?
Understanding your fridge's amperage helps you determine if your electrical circuits can handle the load safely. Overloading a circuit can cause breakers to trip, or worse, start a fire. Knowing the amperage lets you choose the right extension cord (if necessary) and ensure you're not exceeding your circuit's capacity.
What does "startup amperage" mean and why does it matter?
Startup amperage, also known as inrush current, is the surge of electricity a refrigerator draws when the compressor first starts. This can be significantly higher than the running amperage. It's important to account for startup amperage when calculating total circuit load to avoid tripping breakers. While your fridge might run at 4 amps, the startup could be 10 or more for a brief time.