The hvac accessories required for the installation of a central air-conditioner mainly include the following: ceiling air diffuser, ceiling air grille, refrigerant pipe, insulation cotton, branch pipe, power line, communication line, power line communication line pipe, PVC condensate drain pipe, suspender, clamp assembly, outdoor unit damping pad, air outlet, etc.

1. Refrigerant pipe: It is the pipeline for refrigerant circulating transmission in the air conditioning system and the bridge for cold and heat transfer.

The wall thickness and pressure resistance of the selected refrigerant pipe shall meet the technical requirements.

Refrigerant pipe shall be free from defects such as sand holes, oxidation, and crack.

Installation requirements: according to the pipe diameter, the refrigerant pipeline shall be equipped with hangers with proper spacing and covered with qualified insulation cotton.

2. Thermal insulation cotton: it is sheathed on the surface of the refrigerant pipeline to prevent the loss of cold heat from the refrigerant pipeline and the generation of condensate during refrigeration operation.

The high-quality B1 grade plates and pipes are printed with white fonts, and the manufacturers are generally identified in English. The fonts are not easy to erase.

The font will remain unchanged after stretching with good quality.

The B1 rubber and plastic products of good quality are rich in incombustible, flame retardant, and smoke-reducing materials. The smoke produced during combustion is of very low concentration and does not melt, and there is no fireball dropping. It has the characteristics of natural extinction.

Thickness requirements of insulation layer:

a. Outer diameter of copper pipe d ≤ Φ Thickness of insulation layer at 12.7mm δ= More than 15mm.

b. Outer diameter of copper tube d ≥ Φ Thickness of insulation layer at 15.9mm δ= Above 20mm.

c. Outer diameter of copper tube d ≥ Φ Thickness of insulation layer at 41.3mm δ= Above 25mm.

3. Branch pipe: whether the refrigerant is used when shunting in the pipeline and the installation level will seriously affect the operation effect and reliability of the system.

The wall thickness of the diverging pipe is good, and the welding quality is good. The pipe will not burst due to high pressure.

Installation requirements: it must be installed horizontally, and there must be a straight distance of 0.5m before and after the branch pipe; Only by strictly following this requirement can the refrigerant between the indoor and outdoor units be allocated in the most reasonable way, and the use effect of each indoor unit and the reliability of the outdoor unit can be guaranteed.

4. Power line: the internal and external power connection lines shall be selected in strict accordance with the product requirements. The internal power supply of the same system must be uniformly powered to ensure the normal operation of the system.

The copper core of qualified copper core wire shall be purple red, shiny, and soft.

The copper core of the fake copper core wire is purple-black, yellow, or white, with many impurities, poor mechanical strength, and toughness. It will break with a little force.

When the wire diameter is selected correctly, the power supply wiring must use wire lugs to ensure that the wiring is firm and reliably grounded.

5. Communication line: it is used for communication transmission between internal and external computers. Shielded wire is selected and connected in series. If unqualified communication lines are selected, the stability of system communication and operation effect will be affected.

Qualified copper core wire copper core shall be purple red, shiny, and soft.

The copper core of the fake copper core wire is purple-black, yellow, or white, with many impurities, poor mechanical strength, and toughness. It will break with a little force.

Wiring requirements: the three-core shielded wire must be used, the shielding layer must be grounded, the wiring must be firm, and the shielding layer must be wrapped with power tape to prevent the copper wire from overlapping with other terminals, causing abnormal communication.

6. Power line and communication line pipe: When laying a power line or communication line, in order to ensure that the line will not be damaged during installation, the communication signal will not be interfered with by strong electricity and can be reliable and durable for a long time, the line must be threaded separately.

The power line and signal line cannot be threaded in the same line of pipe, and must be separately threaded at an interval of more than 300mm;

When the line comes out of the junction box and connects to the power terminal of the air conditioning equipment, it needs to be protected with a plastic corrugated pipe, and the connection between the plastic corrugated pipe and the junction box needs to be wrapped with black tape.

7. PVC condensate drain pipe: connect the drain outlet of each indoor unit, and timely drain the condensate generated during the cooling operation of the indoor unit; The condensate drain pipe must be covered with insulation cotton with a thickness of no less than 10mm to prevent condensate from generating on the surface of the pipe.

The pipe diameter shall be regular, the thickness shall be uniform, and the color shall not be yellow.

The hanger spacing of the condensate pipe must be reasonable, with a slope of 1/100 towards the pipe drain.

8. Composite air duct material: It is used for making air ducts for the outgoing and returning air of the internal machine. It has the characteristics of small air resistance, good insulation effect, etc., and effectively ensures the operation effect of the air conditioner.

Check the material density according to the material density table provided by the manufacturer to confirm the quality.

Knock the composite materials to confirm the quality, and the sound is pleasant;

When the air duct is connected with the internal unit, a canvas soft connection shall be made to reduce vibration noise; The air duct hanger shall be arranged reasonably to ensure that the air duct is hoisted firmly; The size of air duct and air outlet shall be reasonable to ensure the air outlet effect of the air conditioner.

9. Hanger rod and clamp assembly: It is used to fix refrigerant pipelines and drainage pipelines. The hanger rod and clamp are used together. The distance between hangers is determined according to pipeline materials and pipe diameters to ensure that the pipeline is stable and does not sink.

Installation requirements: boom shall be installed at the bend and branch pipe of the pipeline for reinforcement; According to the pipe diameter, appropriate spacing shall be selected for boom reinforcement. At the same time, PVC pipe shall be padded at the position of the clamp for protection to prevent damage to the insulation cotton and water dripping.

Damping pad for outdoor unit: it is placed at the bottom of the foot of the outdoor unit to effectively reduce the vibration and noise of the outdoor unit. Improve the comfort of the air conditioner.

10. The thickness of the damping pad shall not be less than 50px, and it shall be uniform and not easy to deform and crack.

The compression strength of the damping pad shall be able to bear the weight of the outdoor unit, and it is not easy to deform and crack after being padded with the outdoor unit.

Installation requirements: the shock pad shall be fixed with the outdoor unit foot, and the installation foundation must be horizontal. After installation, swing the outdoor unit vigorously to confirm whether it is firm and reliable.

11. Requirements for copper pipe welding: During the welding of the refrigerant pipe, nitrogen must be continuously filled into the pipe, and the pressure shall be controlled at about 0.2~0.3kgf/cm2 to ensure that there is no oxide skin in the refrigerant pipe.

Welding requirements: During the welding of refrigerant pipe, nitrogen must be continuously filled, and the airflow size should be controlled appropriately.

The place where the nitrogen charging hose is inserted into the copper pipe port must be wrapped well without air leakage.

The nitrogen filling path must be reasonable, there must be only one outlet, and the nitrogen must flow through the pipe welding point where it is welded.

When two refrigerant pipes with equal pipe diameters are connected, an expansion pipe must be used to ensure the welding quality.

12. Ceiling air Diffuser: small parts are often overlooked by many consumers, but this part has a great impact on the interior decoration effect.

There are two kinds of materials for common air diffusers: ABS air diffusers and aluminum alloy air diffusers. Both air diffusers have advantages and disadvantages. It is made of ABS engineering materials and is not easy to fall. However, the material has a certain coefficient of thermal expansion and cold contraction, so it may make a squeak during use, and the air diffuser may also have a slight arch in winter when the temperature is low. After a long time of use, the air vent will turn yellow, which is not easy to clean. The advantage is that it is not easy to deform and discolor. However, due to the very fast heat transfer speed of aluminum alloy, it is easy to condensation during use in summer. In serious cases, there will be water drops.