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Do Hard Start Kits Save Energy? Make Your AC Energy Efficient

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I used to dread turning on my air conditioner because I feared how much electricity it would need.

That’s when I came across the fantastic hard start kits, which saved me money and sped up the startup procedure.

So now I don’t have any dimming lights or anxiety, so you may be wondering do hard start kits save energy, and how? Read on to find out more.

A Hard start kit minimizes the time and quantity of power required for the compressor to start. Consequently, saving time and effort since efficiency is paramount. In addition, installing a hard start kit for an AC saves energy and extends its lifespan, as replacing a compressor may be costly.

Both hard and soft start kits could help save energy.

Unfortunately, most AC compressors don’t have hard or soft start kits.

Below I cover some of these kits’ most common questions, benefits, and facts. 

Saving Energy With A Hard Start Kit

During the initial startup of an AC system, the electrical current is often significant, putting a tremendous amount of stress and excess heat on the compressor.

But a hard start kit can improve the compressor’s life expectancy by reducing the stress on the windings.

In your experience, you will soon realize that reducing the inrush current while starting up helps save operational costs.

Therefore, when purchasing a new AC, installing a hard start kit will be essential in the long run. Installing a hard start kit for older AC units is even more important.

The Benefits Of A Hard Start Kit In An AC

A capacitor inserted in the HVAC system is known as a “Hard Start Kit”

Even in low-voltage situations, your AC compressor can start with the aid of this gadget.

However, as the age of the compressor in your air conditioner may cause it to have trouble starting, it will work more efficiently if you use a hard start kit.

The added expense of installing a hard start kit is something everyone should make. The cost of replacing a compressor is high, and one should always place a high value on conserving resources.

In addition, hard start kits save electricity and enhance the unit’s longevity, which adds to the air quality in a house.

A hard start kit will help you maintain a constant energy consumption level and guarantee that your motor starts up quickly when you turn it on.

However, the real benefit lies in getting the unit up to speed faster and with less power drain.

As a result, before purchasing a hard start kit, speak with an HVAC expert for advice on which hard start kit you will need for your unit.

Will A Hard Start Kit Make Your AC More Energy Efficient?

Yes, the electrical efficiency when starting up your AC is as high as 98% when using a hard start kit; without one, it is only around 50%.

So with this efficiency reducing heat and wear on your compressor and other essential components of your AC, how can you resist using a hard start kit?

What is the main difference between hard and soft start?

By controlling the current that runs through the start and run windings, soft start kits are there to reduce the starting current of your compressor.

Therefore, it will provide more control over the current and avoid overheating the circuit. They are more prevalent in smaller AC units with lower amperage requirements and usually cost more. 

Most hard start kits have a start capacitor and a positive temperature coefficient device.

These devices got designed to provide an electrical boost in your AC system compressor when startup occurs, therefore; saving you energy by shortening the startup process.

They are more prevalent in larger AC units with higher amperage requirements. 

Are Hard Start And Soft Start Kits Necessary?

In many homes, when startup occurs from a large motor, for example, an air conditioner, it is common for LED lights to either flicker or dim because of system voltage reduction.

Installing either a soft start kit or a hard start kit can quickly solve the problem of flickering lights.

Both hard and soft start kits consist of a capacitor and relay. However, installing a hard start kit on aging electrical motors in need of assistance when starting up is more common.

Soft start kits limit the inrush currents and improve the power source’s stability.

In addition, soft and hard start kits help motors start up much faster, and they are a lot more efficient because they enable power-factor correction for low power factor motors.

Motor efficiency is essential in the long run.

What Does A Compressor Saver Kit Do?

The compressor saver is linked to the condensing unit to save the air conditioner windings from overheating.

In certain circumstances, the 5-2-1 Compressor Saver reduces the time it takes for your compressor to start by as much as 50 percent, protecting these critical components.

Of course, they can cost as much as three times more than a Hard Start Kit, but the Compressor Saver can help your air conditioner function more efficiently and save you money in the long run.

When Do You Need A Hard Start Kit?

It is essential to pay attention to your air conditioner, and the moment you notice the following signs in your AC unit, you should install a hard start kit immediately:

  • You hear a clicking sound when your compressor turns on
  • When you start up your AC, you notice the flickering of lights which generally means your AC unit is using too much energy
  • When the compressor trips the circuit breaker of your AC

Can A Hard Start Kit Cause Damage To A Compressor?

The air conditioning system compressor motor startup process requires around 4 to 8 times more electricity than simply running.

With time this intense shock of electricity could cause damage to your compressor in the long run if you do not pair it correctly.

On the other hand, a properly paired hard start kit shortens the startup period of the compressor as well as the amount of energy consumed to start up.

Finding The Correct Size Kit

When you decide to purchase a startup kit, for example, a 5-2-1 compressor motor saver, you will realize that you would need to buy a kit that would fit the exact size of your air conditioner.

You can purchase kits for an air conditioning system ranging from 1-3 tons, 3.5-5 tons, and 4-5 tons.

If you choose a startup kit that is inadequate for the size of your air conditioner, the entire system might suffer.


As long as you’re using a hard start kit, a new compressor saver, or a soft starter, you’ll be able to save money and extend the life of your air conditioner.

An air conditioner uses more energy when it is started up than if it is left running in the same way. Be sure to pair it correctly with the type of AC compressor you have, and it will be a win-win situation.