A hard start kit is utilized in air conditioning and heat pump systems to assist the compressor in initiating operation more easily. These kits are particularly beneficial when power source issues exist, such as fluctuations or low voltage. Installation is often performed by individuals with experience working with high voltage, though professional assistance is recommended if there is any uncertainty.
What is a Hard Start Kit?
Compressors require a significant amount of power upon initial startup—approximately four to eight times more than during normal operation. A hard start kit provides an additional boost of power during this critical phase. The kit incorporates a capacitor that is disconnected by a relay after the compressor has started, ensuring efficient operation. Air conditioning and heat pump systems often already include a start/run capacitor; a hard start kit adds an additional capacitor specifically for the compressor.
Why Install a Hard Start Kit?
Several scenarios can benefit from the installation of a hard start kit. These include:
- Helping older air conditioning systems operate more efficiently.
- Improving performance in off-grid power systems where voltage fluctuations may occur.
- Reducing voltage drops during compressor startup, which can manifest as dimming lights.
- Providing increased torque to PSC (Permanent Split Capacitor) compressors, which are known for their low starting torque.
The installation of a kit can lower the maximum in-rush amps during startup while maintaining consistent operating amps. It is important to note that older air conditioning systems may already have a hard start kit installed, as they were commonly used in the past but were sometimes removed due to cost considerations and improvements in system design.
Types of Hard Start Kits
The documentation references examples of hard start kits available on Amazon. One example is the “Ultra Durable 5-2-1 CSR-U1 Compressor Saver Hard Start Capacitor by Blue Stars,” compatible with 1 to 3-ton units. Another example is the “AMI PARTS SPP5 Hard Start Capacitor Relay,” designed for use with 1/2 through 10 H.P. systems. It is crucial to always follow the specific instructions included with the purchased kit, as configurations may vary.
How to Install a 3-Wire Hard Start Kit
The following steps provide a general overview of installing a 3-wire hard start kit. It is essential to turn off the power to the unit at the breaker or disconnect before beginning any work.
- Remove the panel on the outside condensing unit to access the internal components.
- Mount the hard start kit inside the panel. The capacitor will typically be secured with a zip tie, while the relay requires bolting.
- Identify the three wires associated with the kit: Yellow, Black, and Red.
- Connect the Black wire to the common side of the contactor.
- Connect the Red wire to the Run capacitor common side labeled “C”.
- Connect the Yellow wire to a Run capacitor lead labeled “HERM”.
The documentation emphasizes the importance of safety when working with high voltage and recommends consulting a professional if there is any doubt regarding the installation process.
When Should a Hard Start Kit Be Installed?
A hard start kit can be installed when issues with the power source are present. Specifically, it can be helpful in situations where the power source fluctuates or experiences low voltage at certain times. A noticeable symptom indicating the need for a kit is dimming lights when the air conditioner starts. Additionally, these kits are beneficial in off-grid systems where power supply may be inconsistent. The documentation states there are “many scenarios when a hard start kit is beneficial.”
Will a Hard Start Kit Damage the Compressor?
The provided documentation does not indicate that a hard start kit will damage the compressor. In fact, the purpose of the kit is to assist the compressor during startup, potentially prolonging its lifespan by reducing stress on the motor. The relay disconnects the capacitor after initial startup, ensuring the system operates efficiently.
Checking for Existing Hard Start Kits
If an HVAC system is very old, it is advisable to check if a hard start kit is already installed. The presence of a capacitor disconnected by a relay indicates a kit is already in place. This can prevent redundant installation and potential complications.
Summary
Hard start kits are a relatively low-cost solution to assist compressors in air conditioning and heat pump systems during startup. They are particularly useful when dealing with power supply issues or older systems. While installation can be performed by experienced DIY individuals, caution must be exercised due to the presence of high voltage. If any uncertainty exists, it is always recommended to consult a qualified HVAC professional. The kits function by providing an extra boost of torque during the initial startup phase, reducing stress on the compressor and potentially improving overall system efficiency.
Conclusion
A hard start kit can be a valuable addition to an HVAC system experiencing startup difficulties, particularly those related to power supply inconsistencies. Proper installation, following the manufacturer’s instructions, is crucial for safe and effective operation. While the documentation provides a general overview of the installation process, professional assistance should be sought if there is any hesitation or lack of experience working with electrical components.