What is a Hard Start Kit for air conditioner ?
What is a Hard Start Kit and Does My AC Need It?
Having an air conditioner that fails to start up properly can be extremely frustrating, especially during the sweltering summer heat when you need cooling relief the most. If your AC unit struggles turning on or makes concerning noises when it tries to activate, the root cause likely stems from an issue known as a hard start. The good news is there’s a relatively inexpensive and straightforward solution—installing a hard start kit.
This article will provide a comprehensive look at everything you need to know about hard start kits. We’ll start by explaining what exactly a hard start is and the reasons why it happens in air conditioning units. Next, we’ll discuss how to diagnose hard start problems based on common symptoms. After covering how to identify the issue, we’ll explore what a hard start kit is and how it provides the fix. We’ll also compare the pros and cons of do-it-yourself installation versus hiring an HVAC technician to handle it. By the end, you’ll have a complete understanding of this common AC problem and solution.
What Does “Hard Start” Mean for an Air Conditioner?
The term “hard start” refers to when the compressor inside an air conditioning unit has difficulty starting up. Air conditioner compressors require a strong jolt of electrical power to begin operating. This surge of energy gets the compressor motor going from stationary to full speed. If this initial power surge is lacking, the compressor strains against itself trying to start moving. This struggle to start is what’s known as a hard start.
Some common signs that an AC system has a hard start problem include:
- The compressor makes straining noises when trying to turn on, like humming, clicking, or buzzing. This happens as it tries in vain to start against inadequate power.
- It takes several cycles of trying for the compressor to actually start up and begin cooling. You’ll notice it trying to startup repeatedly.
- The AC cools inconsistently, working fine for a while but then failing. Hard starts cause intermittent operation.
- You notice a burning plastic smell coming from the outdoor AC unit as components overheat.
- Your electrical breakers trip frequently as the system pulls excess power struggling to start.
These hard start issues typically develop over years of use as compressors wear out. The specific component that fails is called the start capacitor. This capacitor provides the initial power surge to get the compressor motor spinning. When it fails, the compressor lacks the starting power it needs.
What Is a Hard Start Kit?
Now that you understand hard starts, let’s discuss how a hard start kit provides the solution. A hard start kit is a supplementary device designed to give an AC compressor the boost it requires to turn on properly.
The kit consists of two key components wired together—a start capacitor and a potential relay. The start capacitor has higher capacitance, meaning it can store more power, compared to the original failing one in the AC unit. This greater capacity provides the extra surge of starting power the compressor needs.
The potential relay serves a vital safety purpose. It disables the start capacitor after the compressor successfully starts up and gets running. This prevents the capacitor from overheating and becoming damaged from extended use.
Once installed, the hard start kit will activate whenever you switch your AC system on. It provides the required power boost so the compressor can start immediately without straining. This prevents common problems like tripped breakers, burning smells, and intermittent cooling operation. It’s an easy, cost-effective solution that can extend the life of an aging AC unit.
Warning Signs Your AC Needs a Hard Start Kit
If you notice any of the following warning signs, your air conditioner likely has a hard start problem that installing a kit can resolve:
- Buzzing, humming, or clicking noises – As the compressor strains against inadequate power to start, it often produces audible noises.
- Frequent tripping of circuit breaker – Drawing so much current to start overloads the compressor and trips your home’s electrical breaker.
- Burning plastic smell – The excess strain also overheats internal compressor components, releasing a noticeable burning odor.
- AC cooling inconsistently – Intermittent cooling operation commonly points to a failing start capacitor.
- Outdoor fan delays starting – The fan relies on the compressor running properly before it can startup.
- AC running but room not cooling – If the compressor works but cold air is weak, low refrigerant is likely the issue. The hard start kit fixed the startup problem but other AC faults remain.
If you notice your air conditioner exhibiting any combination of these symptoms, installing a hard start kit should resolve the problem. AC units suffering from hard starts will only deteriorate further over time without the help of a kit.
Pros and Cons of DIY Hard Start Kit Installation
Installing a hard start kit is straightforward enough for a DIY project, but there are important factors to weigh first.
Potential Pros of DIY Installation:
- Cost savings – Doing it yourself avoids paying HVAC service call fees.
- Convenience – You can install at your own pace rather than waiting for an appointment.
- Satisfaction – Successfully tackling the repair yourself can be rewarding.
Potential Cons of DIY Installation:
- Safety risk – Serious injury can result from mishandling live electrical connections.
- Voided warranty – Manufacturers won’t cover parts you damage during installation.
- Improper installation – If the kit isn’t wired correctly, it won’t work right.
- Misdiagnosis – The kit may temporarily mask symptoms caused by other undiscovered AC faults.
In general, DIY installation works well for handy homeowners comfortable working with electrical wiring. But those uneasy tackling the project themselves may want to hire an HVAC technician to ensure proper installation and diagnosis.
Step-by-Step Hard Start Kit Installation Guide
If you decide to take the DIY route, follow this step-by-step installation guide:
- Turn off power to the AC unit at the breaker and disconnect it. Double check power is off for safety.
- Remove the protective outer cabinet to access the internal wiring.
- Locate the existing start capacitor, usually mounted near the compressor. Remove any protective cover.
- Take photos of all wiring connections for reference later.
- Carefully discharge the old capacitor to prevent shock risk.
- Disconnect and fully remove the original start capacitor.
- Install the new hard start kit, matching the previous wire connections.
- Securely mount the potential relay and new capacitor in place.
- Replace the cover and reinstall the outer cabinet.
- Restore power and test the AC operation.
- Add any needed refrigerant if issues like weak cooling remain.
These basic steps apply to most standard AC unit models. But always check your specific system’s manual for any variations in design. Thoroughly researching the installation process ahead of time is crucial for safe and effective DIY hard start kit installation.
When Calling an HVAC Technician is the Better Option
Despite the temptation to DIY, hiring an experienced HVAC technician is the wise choice in certain situations:
- You don’t feel fully confident handling the electrical work safely.
- Your AC unit is still under warranty that DIY repairs would void.
- You lack the technical skill or tools to properly install the kit.
- You want an expert diagnosis to check for other hidden issues.
- Your system uses newer puron/R410 refrigerant requiring special equipment to add more.
While DIY hard start kit installation often succeeds, having an HVAC professional handle it is the only surefire way to guarantee proper diagnosis, installation, and preservation of your unit’s warranty coverage.
Frequently Asked Questions
Before deciding whether to install a hard start kit yourself or call in an HVAC technician, it helps to have common questions answered:
- How much does a hard start kit cost? DIY kits cost $50-100. Add $100-200 for professional installation.
- Where does the hard start kit install? It directly replaces the original start capacitor, typically mounted near the compressor.
- How long does a hard start kit last? Approximately 5 years. But it extends the lifespan of the AC compressor.
- Can I just replace the capacitor instead? Yes, but a hard start kit provides superior starting power and protects the new capacitor.
- Will a hard start kit fix low refrigerant? No, it only aids compressor starting. Low refrigerant causes separate cooling issues.
- Do I need refrigerant with a hard start kit? Often yes, as low refrigerant worsens compressor straining at startup.
- Is a hard start kit worthwhile? For under $100 it can add years of life to an aging AC system, so it’s very cost-effective.
Accurately diagnosing whether your air conditioner truly needs a hard start kit is best left to an HVAC technician. But once the need is confirmed, these kits provide an easy fix for restored cooling operation. With proper installation, your AC will start effortlessly for many more hot seasons.
