It is said that the central air conditioner should be installed according to its quality and quality. In fact, the equipment purchased by the central air conditioner is only a "semi-finished product". It needs a series of installation and commissioning before the central air conditioner can operate normally. If the installation and commissioning of the central air conditioner is unreasonable, the most common problems such as water leakage, fluoride leakage, excessive noise, and weak cooling heat will occur. This article collects some common problems, hoping to attract more attention of refrigeration personnel through this article.
1. The drainage of fan coil is not smooth
If the water leaks outside the fan coil water collecting tray, it is mainly because there is a problem with the insulation material. If the water leaks inside the water collecting tray, it is because the fan coil condensate pipe is blocked and the condensate overflows. We just need to dredge the condensate pipe. Fan coil if If there is no condensate drainage pump, it must rely on slope gravity drainage. Then, the gradient of branch pipe of condensate pipe shall be greater than 1%, and the gradient of main pipe of condensate pipe shall be greater than 5 ‰
2. Tee is not installed horizontally
The lack of horizontal installation of three-way is likely to cause system bias, and some of the internal machine capacity is insufficient. Attention must be paid! The internal machine branch tee must be placed horizontally. After the tee, it is not allowed to turn at once. The branch tee cannot be installed vertically or obliquely. After the tee forks, the pipeline should continue to run horizontally along the original direction (when running horizontally) for at least 1m before turning or running upward or downward. The following pipes should be re run.
3. There is no sealing protection at the pipeline interface
There is no sealing protection at the pipeline interface, and there are many impurities and dust in the pipe. If it is not handled in time, the moisture and dust in the air are easy to enter the copper pipe, polluting the system, causing the system to be dirty or ice blocked, which may severely burn the press. Therefore, when the pipeline is not in operation, all interfaces of the pipeline shall be sealed and protected in time to prevent dust and moisture from entering the system. If there is dust entering the system, the operation method of nitrogen purging must be used.
Operation method of nitrogen purging: effectively connect one end of the copper pipe to the outlet end of the pressure reducing valve of the nitrogen cylinder without gaps. Block the other end of the copper tube with multi-layer white gauze or mask by hand, and release it when the pressure is high.
4. No nitrogen charging protection
There is no nitrogen filling protection during welding. Without nitrogen filling protection, there will be too many impurities in the pipe during welding and the oxide skin will be serious, which can seriously block the refrigeration system. Therefore, during copper pipe welding, sufficient nitrogen must be filled into the copper pipe, and the nitrogen must flow through the welding part to protect the inside of the copper pipe. It is required to fill nitrogen for a period of time before welding operation. At the same time, the welding time should not be too long to reduce the oxide scale in the pipeline and avoid system operation blockage.
One of the biggest problems of multi split installation is welding. If you can control the standard welding operation well before installation, the service life of the air conditioner will be improved, the failure rate will be reduced several times, and the difficulty of maintenance will be reduced in the future.
5. No pressure maintaining and vacuum pumping, wrong refrigerant filling
Air tightness test must be carried out to avoid leakage of equipment. The test pressure of R410a refrigerant pipe is 4.0MPA, and the pressure gauge reading is checked after the pressure is maintained for 24h. The refrigerant pipe is qualified if the pressure drop is not more than 1%.
After the operation is completed, vacuum drying shall be carried out, and the vacuum shall be pumped from the gas-liquid pipe for two hours and maintained for one hour. If the pressure does not rise, it is qualified. be careful! If the equipment is not vacuumized, if the moisture content of the system exceeds a certain limit, it will form an ice block at the node, making the refrigerant unable to circulate normally. Moreover, the water reacts with the refrigerant chemically, and the generated hydrochloric acid and fluoric acid will damage the insulation layer of the compressor. The oxygen in the residual air reacts with hydrochloric acid and copper to produce copper plating, which corrodes copper and iron parts in the system pipeline and shortens the service life of system parts.
6. The cable is not connected tightly, and the communication cable is connected incorrectly
The power line of the equipment is not tightly connected, which will cause poor contact. After a period of operation, the line may catch fire or the press may burn down. The wire is not tightly connected. Most of the time, the screw is twisted. Although the screw has been tightened, the wire is still loose.
The wrong connection method of the communication line will cause abnormal communication between internal and external machines, especially when the machine is in failure. Because the communication line is hidden and there are many lines, it is very cumbersome to repair the unit, which brings great inconvenience to the maintenance personnel. According to the installation specification, the communication line must be connected with the two core shielded wire of the metal mesh shielding layer, and the communication line of the internal machine must be connected with the method of head to tail connection. The internal machine must be connected in turn, and the communication line cannot be connected in the way of split in the middle, otherwise the communication of the whole system will be abnormal and cannot operate normally.
7. Influence of lamp slot and strip on heating
The influence of light slot and light strip on heating. The light slot or light strip is designed in front of the outlet of the multi split air conditioner. When the air conditioner heats in winter, hot air will be concentrated above the room. The whole activity space will feel insufficient heat, which will take a long time to feel hot. Owners who need to use multi split air conditioners for heating in winter need to pay attention to this. From Xiao Bian's personal experience, only the ceiling is really hot.
8、 The air supply pipe bends too quickly
In pipe layout, the bend angle of supply air duct is a key factor. Too fast bending angle will significantly increase the air flow resistance, resulting in poor air supply, affecting the uniformity of indoor air distribution, thus reducing the comfort and energy efficiency of the air conditioning system. In order to ensure unimpeded air flow, it is recommended that the radius of curvature of the elbow should be at least 1.5 times the pipe diameter. Try to use a gentle elbow design, or use special elbow fittings to reduce air flow resistance.
9. Gas wiring problems
In electrical installation, the selection of power cord specification is very important. If the load capacity of the power line is lower than the requirements of the air conditioning unit, overload may cause wire heating, insulation aging, and even short circuit fire and other serious safety accidents. On the contrary, if we choose wires that are far beyond the required specifications, although the safety is guaranteed, it will increase unnecessary costs.
