AIR CONDITIONER split type, 4T
Valid Article
Split Air Conditioner
Definition
Air conditioners are devices designed to cool indoor spaces by removing heat from the indoor air and transferring it outside. Air conditioners don't bring in fresh cool air from the outdoor, instead, they recirculate and cool the existing indoor air.
Split air conditioners are made up of 2 separate units: an indoor unit that is called the evaporator unit and an outdoor unit called the condensing unit. The indoor and outdoor units are connected together by copper pipes (to manage the flow of the refrigerant in the form of gas or liquid) and electrical cables (power supply and communication cable). The unit also comes with a condensate drainpipe connected from the indoor and a remote control.
Specifications
There are different types of split air conditioners.
Inverter vs non-inverter:
Invert ACs require much lower starting current and will run more efficiently overall, whereas non-inverter also known as on/off will either work at full capacity or off. Inverter ACs are the recommended type because they consume less energy.
Cooling air conditioner vs heat pump:
A heat pump can be used for cooling and heating by reversing the refrigeration cycle. Heat pumps should be selected when heating is required. A cooling air conditioner can only cool air and not heat.
This description only covers single split air conditioners.
Components
- Outdoor unit containing the compressor, condenser and fan
- Indoor unit containing the evaporator, filter and blower
- Factory charged refrigerant gas
- Copper pipes with insulation
- Electrical cables
- Condensate drainpipe
- Remote control
Technical specifications
Size, cooling capacity:
Standard sizes of air conditioners are defined by their cooling capacity.
- 1 Ton = 1.5 HP = 12,000 BTU/h = 3.5 kW cooling capacity
- 1.5 Ton = 2 HP = 18,000 BTU/h = 5.3 kW cooling capacity
- 2 Ton = 2.5 HP = 24,000 BTU/h = 7.0 kW cooling capacity
In order to choose the right AC capacity for a defined space, this tool https://sherlog.msf.org/articles/1499/aircon-calculation-tools.html is used to calculate the capacity required taking into account multiple factors that affect the cooling capacity, like: room size, ambient temperature, type of walls, insulation,..
Refrigerant gas:
All active cooling systems require a refrigerant gas to operate. It is the process of changing the gas from vapor to liquid and vice versa that provides most of the heat transfer. Unfortunately these gases, when released into the atmosphere have very serious effects on the environment; and have ozone depletion potential (ODP) and global warming potential (GWP). Different types of refrigerants have different ODP and GWP, the following types of refrigerant gases are the most commonly used in ACs:
R22 | R410A | R32 | R290 | |
OPD | 0.055 | 0 | 0 | 0 |
GWP | 1,810 | 2,090 | 675 | 3 |
Flammability | No propagation of flame | No propagation of flame | Low flammability | High flammability |
Refrigerants are generally not interchangeable. It's important to select a system that runs on a refrigerant that is available locally in case it needs to be refilled.
Energy efficiency ratio:
The efficiency of an air conditioner is expressed as the Energy Efficiency Ratio (EER) either expressed as the [W of cooling / Wh of energy consumed \] or in [Btu/h of cooling / Wh of energy consumed]. The higher the EER, the better the efficiency is. It is important when comparing EER of different ACs to make sure that the EERs are expressed by the same unit of measurement.
Class A conditioners have the highest efficiency. Consult the table below with EER values measured in BTU/Wh
A | EER > 10,9 |
B | 10,9 > EER >10,2 |
C | 10,2 > EER > 9,6 |
D | 9,6 > EER > 8,9 |
E | 9,0 > EER > 8,18 |
Transport Dangerous Goods
Below gas are flammable take this into account for transportation and handling:
- R32: low flammability
- R290: high flammability
Supplied with the Article
- Technical sheet and user manual.
- Mounting brackets and vibration pads to mount the outdoor unit are sometimes supplied with the unit.
To be Ordered Separately
- Spare parts should be ordered when purchasing a split AC and notably PCBs.
- If mounting brackets and vibration pads are not supplied with the unit, they should be ordered separately for the installation of the outdoor unit.
- Additional copper pipes if needed.
- It is recommended to install a voltage limiter PELEVOLL230F to protect against high and low voltages, brown-outs, power back surges and voltage tips. Newer AC are more electronic and will be more sensitive to voltage fluctuations.
Instructions for use
Instructions to install wall mounted split ACs:
Maximum pipe length between indoor and outdoor unit should be respected. The maximum allowable distance is indicated on the technical sheet (usually less than 15m).
Maximum allowable level difference (vertical) between indoor and outdoor unit should be respected. This level difference is indicated on the technical sheet.
Outdoor unit properly mounted to avoid vibrations.
Placement of indoor unit:
- Clearance of at least 150mm between the indoor unit and ceiling
- Clearance of at least 125mm between the indoor unit and walls
- Indoor unit should be at least 2.3m above floor
- Avoid installting the indoor unit above a closet, behind a screen/ monitor or close to a diffuser (exhaust or supply)
Placement of outdoor unit:
- Clearance of at least 600mm from the front of the unit (the fan side)
- Clearance of at least 300mm from the rest of the sides
- Clearance of at least 600mm from the top of the unit
Pipework should be done correctly to avoid pinching. All pipes should be insulated.
Precautions for Use
- Avoid obstruction of the airflow:
- Avoid blocking the air inlet and outlet or placing objects near the units that could obstruct the airflow.
- Avoid direct sunlight:
- Minimize direct sunlight exposure to the indoor unit by using curtains or blinds during the hottest parts of the day. This reduces the workload on the air conditioner.
- Avoid overworking the unit:
- Avoid overworking the air conditioner by closing doors and windows in the room being cooled or heated.
- Temperature settings:
- Avoid setting the temperature too low in cooling mode or too high in heating mode, as this can strain the unit and increase energy consumption. Set the temperature to a comfortable level (21°C – 25°C) and consider using programmable thermostats to optimize energy usage.
- The air swing of most indoor units can be adjusted:
- It's best practice to fix the air swing: horizontal blow out of air without swinging over the horizontal axe nor vertical axe
- You can recognize this position by checking the position of the louvers of the indoor unit, they should be at 90°.
- Use eco mode:
- Many modern air conditioners come with an eco-friendly mode that adjusts settings to conserve energy while maintaining comfort.
- The ionizer option:
- Some AC split indoor units have an ‘ionizer' option which is a technique to sterilize the air. However, it's worth noting that some studies suggest that the effectiveness of ionizers in significantly improving air quality may vary depending on factors such as the size and type of particles present in the air, as well as the specific design and performance of the ionizer. Additionally, excessive use of ionizers in poorly ventilated spaces may lead to increased levels of ozone, which can be harmful to health. It is recommended not to use this option.
Maintenance
Maintenance of split ACs should be done regularly to insure proper functioning of the unit.
Following the preventive maintenance protocols, maintenance for indoor units should be done on a monthly basis and maintenance for outdoor units should be done every 3 months, except in dusty areas to be on a monthly basis.
Preventive maintenance protocols are found in the knowledge base of the different OCs or reach out to the HVAC referent.