Choosing a central air conditioning system for the first-time home renovation certainly requires a lot of research. It's different from a regular air conditioner, where design and installation significantly impact the effectiveness. Even scarier is that the more online guides you read, the more confused you get, and if you're not careful, you might..."Bargain Deals and Ceiling Price Increases Trapped, Ceiling Removals Repeatedly. Don't worry, check out this new 2025 "Quick Reference Guide for Newbies to Avoid Pitfalls" in just 10 minutes, understand central air conditioning with minimal effort, and directly copy the homework!"

Complete Guide to Central Air Conditioning Selection and Installation

Central Air Conditioning System Types

Central air conditioners are primarily categorized into two main types: water systems and refrigerant systems.

Water system with high comfort level, soft airflow, minimal impact on humidity, perfect for health-conscious families with spacious homes.

Fluoride Systems, featuring rapid cooling and heating with high efficiency and energy-saving properties, are perfect for households that prioritize efficiency and quick heating.

The multi-split system in the home air conditioning field is more mainstream now.

2. Key Selection Criteria

When selecting a central air conditioner, consider the following points:

a. Brand and After-Sales: Central air conditioning is a "70% installation, 30% product" scenario. Choosing a brand is not only about product quality but also about the reliability of after-sales service. Renowned brands like Daikin, Hitachi, Gree, Midea, and Haier usually have more comprehensive service networks and warranty systems. Make sure to confirm the warranty period (commonly 3 years, 6 years, or even 10 years) and whether it is a manufacturer's direct warranty or a dealer's warranty.

b. Efficiency Grade: Choose products with the highest efficiency level. Pay attention to the Energy Performance Ratio (IPLV), as the higher the value, the more energy-efficient the air conditioner is. For instance, some high-end brands have an IPLV value above 7.6.

c. Cooling/Heating Capacity: Calculate the required cooling capacity based on the room area. Generally, estimate the cooling capacity at 150-220W per square meter. For instance, a 15-square-meter bedroom would need approximately 2250-3300W of cooling capacity (about 1.5 horsepower). Also, consider heating needs, especially in northern regions. It's crucial to inquire about the heating power and performance under high altitude and low-temperature conditions.

d. Noise Level: Bedrooms require high levels of quiet. Pay attention to the operating noise decibel (dB) level of the indoor unit when making a purchase. Good products can operate with a noise level as low as 18-22 dB, making them almost inaudible.

e. Special Features: Consider the need for additional functionalities such as formaldehyde removal, smart control (e.g., remote operation via a mobile app), and self-cleaning capabilities.

3. Installation Precautions

The installation of central air conditioning is crucial; please pay attention to the following points:

a. Installation Timing: The installation of central air conditioning must be integrated at the early stage of renovation and during the electrical and waterworks modification phase. This is because all pipes and wiring need to be laid out before the ceiling and walls are sealed.

b. Installation Location:

Outdoor Unit: Place in a well-ventilated area, away from heat sources and flammable materials, ensuring ample space for heat dissipation and maintenance.

Indoor unit: Maintain a distance of at least 1 cm from the ceiling during installation and secure with a double nut to prevent resonance and noise during operation. Avoid any obstructions such as decorations or chandeliers in front of and below the exhaust outlet to ensure smooth airflow.

c. Pipeline Installation:

Chilled Media Copper Tubes: Nitrogen welding is required during installation to prevent carbon buildup on the inner wall of the copper tubes, which could later lead to compressor damage. The insulation of the pipes must be tight to prevent cold bridging and heat loss.

Condensate Drain Pipe: Installation requires a slope of no less than 1% to ensure smooth drainage of condensate. Connect to the drain pipe as close as possible to avoid backflow, and install an air vent to prevent airlock.

d. Debugging and Acceptance:

After installation, a vacuum operation must be performed (multi-split systems typically require at least 2 hours of vacuuming), to remove moisture and air from within the system.

Subsequently, fill the refrigerant to the specified quantity as required by the manufacturer.

During the acceptance, simply feel the exhaust air temperature (the outlet temperature should be below 16°C during summer cooling), check if the operating noise is within a reasonable range, and inspect for any signs of leakage.

Common Misconceptions and Pitfalls to Avoid with Central Air Conditioning

Misconception: The higher the count, the better.

Correction: Over-sizing the unit leads to frequent start-stop of the air conditioner, which not only consumes more electricity but also results in significant fluctuations in room temperature, affecting comfort. Under-sizing it, however, leads to poor cooling and heating performance, and the machine operates at high load for extended periods. Always calculate the appropriate cooling capacity based on the actual area and room layout.

2. Misconception: Comparing equipment prices only, neglecting installation accessories and after-sales service:

Correction: Before signing a contract, ensure that the quoted price includes all auxiliary materials (such as copper pipes, condensate pipes, insulation, signal cables, etc.), installation costs (drilling, hanging, brackets, etc.), and post-installation tuning fees. Choosing brands or dealers that offer "all-inclusive" service can save a lot of headaches later on.

3. Myth: Installing exhaust outlets in all rooms

Correction: It is generally not recommended to install air conditioner vents in spaces like kitchens and bathrooms. Kitchen fumes can contaminate the indoor unit's fins, and high humidity in bathrooms can easily trigger electrical issues. If a kitchen absolutely requires an air conditioner, a dedicated kitchen air conditioner should be considered.

4. Prevent the purchase of unauthorized products:

Counterfeit Machines: Products sold across regions may not be covered by the brand's official warranty.

Refurbished/Engineering Units: May be second-hand refurbished or products removed after engineering projects; quality and lifespan are not guaranteed.

Avoid pitfalls: Sign an official brand contract, confirm the air conditioner has a unique code and is traceable on the official website, and ensure that after-sales service is provided by the manufacturer, not the dealer.

Three, Recommended Usage and Maintenance

1. Temperature Setting: For air conditioning during summer, it's recommended to set the temperature around 26°C; for heating during winter, the setting should not exceed 20°C. Avoid significant temperature differences indoors and outdoors (usually within 8-10°C) for better health.

2. Avoid Frequent On/Off: Central air conditioning is more energy-efficient when left on for extended periods. Frequent switching off is actually more power-consuming. It's not necessary to turn it off during short absences, such as for 1-2 hours.

3. Regular Cleaning: Clean the return air filter monthly. It is recommended to contact a professional for a deep clean before or after the start of the usage season, including the indoor unit's fins and condensate pan.

4. Regular Power-On: Even during off-season, it is recommended to power on the unit once a month for about ten to fifteen minutes to prevent the compressor lubricant from solidifying and to extend the system's lifespan.