It is said that the quality of a central air conditioner is 70% installation, because when you buy the multi-split central air conditioner , the equipment itself is actually just a "semi-finished product". It requires a series of installation and debugging before the multi-split central air conditioner can operate normally. . If the multi-split central air conditioner is installed and debugged unreasonably, common problems such as water leakage, fluorine leakage, excessive noise, and insufficient cooling and heating will occur. Today, Xi'an Conoson has collected frequently asked questions about multi-split central air conditioners, hoping to help everyone!
1. Fan coil has poor drainage
If water leaks outside the fan coil drain pan, it is mainly due to a problem with the insulation material . If water leaks inside the drain pan, it is condensation on the fan coil. If the water pipe is blocked and condensation water overflows, we only need to clear the condensation pipe.
If the fan coil unit does not have a condensate water drainage pump, it must rely on slope gravity drainage. Then, the slope of the branch pipe of the condensate water pipe should be greater than 1%, and the slope of the main condensate pipe should be greater than 5‰
. 2. The tee of multi-split central air conditioners is not installed horizontally. insufficient. Attention is required! The internal unit's shunt tee must be placed horizontally. After the tee, it cannot be turned immediately. The shunt tee cannot be installed vertically or at an angle. After the tee is bifurcated, the pipeline should continue to run horizontally in the original direction (when running horizontally) ) is not less than 1 meter before turning or running the pipe upward or downward. The pipe should be re-routed as follows.
3. There is no sealing protection at the pipe interface of the multi-split central air conditioner.
There is no sealing protection at the pipe interface of the multi-split central air conditioner. There are many impurities and dust in the pipe. If not treated in time, moisture and dust in the air can easily enter the copper pipe. , contaminate the system, causing the system to be clogged with dirt or ice, which may seriously burn the compressor .
Therefore, when the multi-split central air-conditioning pipeline is not in operation, the interfaces of the pipeline should be sealed and protected in time to prevent dust and water vapor from entering. If dust has already entered the system, the nitrogen blowing operation method must be used. .
Nitrogen blowing operation method: effectively connect one end of the copper pipe to the outlet end of the nitrogen bottle pressure reducing valve without leaving any gaps. Block the other end of the copper pipe with multiple layers of white gauze or a mask with your hands, and suddenly release it when you feel a higher pressure.
4. No nitrogen filling protection
There is no nitrogen filling protection during welding. Without nitrogen filling protection, it will cause excessive impurities in the tube during welding and serious oxide scale, which can seriously block the refrigeration system. Therefore, when welding copper pipes, it is necessary to fill enough nitrogen into the copper pipe and ensure that the nitrogen flows through the welding part to protect the inside of the copper pipe. It is also required that the welding operation can be carried out after filling the nitrogen for a period of time. At the same time, the welding time should not be If it is too long, it will reduce the production of oxide scale in the pipeline and avoid clogging the system.
Note, do not use cold water to cool the welding joint after welding is completed!
One of the problems in the installation of multi-split central air conditioners is welding. If welding specifications can be well controlled before installation, the service life of the air conditioner will be extended, the failure rate will be reduced several times, and the difficulty of future maintenance will be reduced.
5. Failure to maintain pressure and vacuum , and add refrigerant incorrectly
An air tightness test must be carried out to avoid leakage of the equipment. The test pressure of the R410a refrigerant pipe is 4.0MPA, and after maintaining the pressure for 24 hours, check the pressure gauge reading. If the pressure drop is not more than 1%, the air tightness of the refrigerant pipe is qualified.
After the operation is completed, vacuum drying is performed. The vacuum is drawn from the gas-liquid pipe for two hours and the vacuum is maintained for one hour. If the pressure does not rise again, it is qualified. Notice! If the equipment is not evacuated, if the moisture content in the system exceeds a certain limit, ice blockage will form at the throttle outlet, preventing the refrigerant from circulating normally. Moreover, moisture reacts chemically with the refrigerant, and the hydrochloric acid and hydrofluoric acid produced will destroy the insulation layer of compressor .The oxygen remaining in the air reacts with hydrochloric acid and copper to produce copper plating, which corrodes the copper and iron parts in the system pipelines and shortens the life of system components.
Many refrigeration people judge the method of charging refrigerant based on these methods, such as: "Measure high and low pressure", "Measure compressor current", "Observe the condensation on the suction pipe", etc. In fact, these All methods have disadvantages (I have mentioned them in previous posts and will not repeat them here), but "weighing and filling according to the nameplate" is the correct approach.
6. The multi-split central air-conditioning line is not tightly connected, and the communication line is connected incorrectly.
The equipment power cord is not tightly connected, which will cause poor contact. After running for a period of time, the line may catch fire or the compressor may burn out. When the wires are not connected tightly, it is often because the screws are twisted. Even though the screws have been tightened, the wires are still loose.
Incorrect connection method of the communication line will cause abnormal communication between the internal and external machines, especially when the machine fails. Since the communication line is hidden and has many thread ends, it is very cumbersome to inspect the unit, which brings extreme inconvenience to the maintenance personnel.
According to the installation specifications, the communication line must be connected with a two-core shielded wire with a metal mesh shielding layer. The communication line of the internal unit must be connected end-to-end. The internal units must be connected in sequence, and communication cannot be used. Otherwise, the entire system will not communicate properly and cannot operate normally.
7. The impact of light trough light strips on the heating of multi-split central air conditioners
Later, let’s talk about the impact of light trough light strips on heating. Design light troughs or light strips in front of the air outlets of multi-split central air conditioners. In winter, multi-split central air conditioners When heating, the hot air will be concentrated in the upper part of the room. The entire activity space will feel insufficient heat, and it 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 my personal experience, only the ceiling is really hot. The best solution is that the air outlet is flush with the light trough.
