In the HVAC industry, it is often heard that water machines are different from fluorine machines. What's the difference between them?

In the HVAC industry, it is often heard that water machines are different from fluorine machines. What's the difference between them? The biggest difference between fluorine machine air conditioner and water machine air conditioner is the difference of refrigerant.

Take central air conditioning as an example:

Water unit uses water as heat transfer medium to transport cold and heat. This machine circulates water into the room instead of freon. Of course, someone here must ask, the water unit arrived at the room after secondary heat exchange. Will its cooling and heating speed slow down?

The answer is: it will not slow down.

There are two main reasons:

1. At present, the heat exchanger between Freon and water (commonly known as plate heat exchanger) used in water units has high heat exchange efficiency.

2. The indoor unit of water unit and the indoor unit of fluorine unit have different working principles. The cooling capacity released by the indoor unit is related to the medium flowing in the indoor unit and the air volume of the indoor fan.

The medium flowing in the fluorine unit is Freon, which has a large temperature difference between the inlet and outlet, but the air volume of the indoor fan is small. However, the temperature difference between the inlet and outlet of the water unit is small, while the indoor air volume is large. In this way, the total heat transfer and velocity are constant. This is also an advantage of water units. The air supply is soft and won't make people feel hot and cold. In winter, there will be no dry feeling of fluorine system machine caused by too high freon evaporation temperature.

Heating of water units: Larger water units usually use two compressors, which on the one hand is to save energy, on the other hand, it can also play a great role in heating and defrosting. When defrosting a water chiller, generally two compressors defrost alternately, which has the advantage of greatly reducing the heat loss.

In addition, as we all know, water can store heat, and when defrosting, the heat stored in water is enough to release heat indoors. If the design is good, the fluctuation of water temperature difference during defrosting of water chillers is very small, and the indoor temperature will naturally be well guaranteed.

In the process of contact with customers, many people will ask a question, saying that drinking fountains are prone to water leakage. From the working principle, the working pressure of water system is generally less than 3 kg, and the pressure resistance of common materials (mainly pipes) is 16 kg. The working pressure of fluorine plant is 5-7kg for refrigeration in summer and 20kg for heating in winter. In terms of working pressure, which system is the most prone to leakage? Therefore, the most important factor for which system is prone to water leakage lies in the engineering quality and material quality, not in the water unit or fluorine unit.

In the HVAC industry, we often hear about water machines and fluorine machines, so which of these two machines has a brighter future? Large central air conditioning system adopts ordinary water machine; Fluoride is mainly used for household use and VRV. The two will not replace each other, and each has its own market.

What's the difference between Super League and national football? Super League is the China Football League, and the national football team is the national team. Foreigners can join the Super League, but not the national football team. Must be all China or China nationality.

What's the difference between a water softener and a water purifier? Can they replace each other? The water softener is a water treatment device for removing cations of calcium, magnesium and sodium in water and various acid radicals in water. The water that comes out is pure water (note that it is pure water for industry, chemical industry and medicine, not pure water for drinking).

Water purifier is a water treatment equipment to remove impurities in water and improve the quality of drinking water.

They have different structures, different uses and different costs, so they can't replace each other.

What's the difference between sewing agent and porcelain sewing agent? Porcelain caulking agent and beautiful caulking agent are the two most popular tile gap decorations in modern home decoration, but it is difficult for people who come into contact with porcelain caulking agent and beautiful caulking agent for the first time to distinguish them, let alone know which product has better use effect.

First, the difference between materials.

Porcelain sealant generally refers to tile sealant, mainly epoxy resin. With good hardness and flexibility, it is an upgraded product of caulking agent. It can be called two-component joint sealant, but it is different from joint sealant.

Joint sealant is an upgraded product of joint sealant, which is mainly made of new polymer materials, advanced pigments and special materials. Strong decoration, good antifouling effect and high cost performance.

Second, the difference in efficiency.

Although both porcelain joint filler and beauty joint filler are products of ceramic tile joint filling, porcelain joint filler is an upgraded product of beauty joint filler, with high hardness, smooth surface like porcelain and no shrinkage, and the shelf life is more than 10 year. However, the beauty joint filler on the market is a water-soluble product, which has certain shrinkage when used, soft texture and dull surface, and the shelf life is about 2-3 years.

Third, the difference of whiteness.

The difference between sewing agent and sewing agent lies in the whiteness of their colors. The whiteness of porcelain sewing agent is about 86%, and the whiteness of sewing agent is about 95%, with smooth surface and good texture.

Fourth, the price difference.

Because of the high cost and technology, the price of porcelain sewing agent in the general market ranges from tens to tens of thousands of yuan, while the price of beauty sewing agent ranges from tens to hundreds of yuan.

What are macros and macro groups in AES? What's the difference between them? (

1

A macro is a specific code, which is a collection of one or more operation commands.

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2

) macro takes action as the basic unit, and a macro command can complete an operation. Each macro command consists of an action name and an action parameter.

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three

A macro can be a macro collection containing one or more macro commands. If a macro consists of multiple macro commands, its actions are executed in the order of macro commands.

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four

Macros can also be defined as macro groups, and multiple macros can be stored in one macro.

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five

A macro group is actually a collection of multiple macros with different macro names.

1

If the macro group is executed directly, only all macro commands contained in the first macro name will be executed;

2

) to execute.

Macro commands in other macro names need to be executed through event codes that trigger control components, and indirectly through macro commands.

There are aidl and binder mechanisms for communication between android programs. What's their principle and what's the difference? Binder is the driver of the core layer, which is equivalent to a protocol or something. Aidl is actually rpc, which is also the communication between programs, and the bottom layer is also based on binder mechanism.

What is the difference between CPDU and ordinary PDU in cabinet industry? CPDU is a computer monitoring power distributor;

Main uses:

It is widely used for centralized real-time monitoring of CPDU total load current, voltage, power, ambient temperature/humidity/smoke of multiple cabinets in the computer room of data center.

Product features:

Serial communication technology, local centralized monitoring;

PDU is the same as plug-in, but it is more stable.

Guangzhou Peng Hui Network Technology Co., Ltd. is a cabinet manufacturer and seller.

How to distinguish "licensed" mobile phones from "parallel" mobile phones? What's the difference between them? Parallel imports that have not paid customs duties in China should not be refurbished now. There is no difference between refurbished products and licensed products. Licensed products are not guaranteed. There are few defective products in licensed products, not necessarily in parallel imports.

What's the point? What is the pattern? What is the difference between two keys (key in English) means that the melody of music has a certain pitch position, and different keys represent different pitch positions. For example, the pitch of D key is higher than that of C key, Modal (mode in English), and several high and low keys are organized together according to a certain interval relationship around a stable central tone, which becomes an organic system called mode. Tone and mode are two completely different concepts, but they are inextricably linked. In musical works, the pitch position of a mode is always specific and definite, so any mode must belong to a certain key. On the contrary, a key must include many different or the same tonic modes. Take C mode as an example, which usually includes C major mode, A minor mode, C palace mode, D quotient mode and E angle mode. Usually, when expounding the concept of mode, the central tone of mode-tonic tone is often used as the starting point and the end point, and other sounds are arranged in the form of scale in pitch order, which is called mode scale. In different historical periods, different nationalities and regions have formed various models. Various modes have their own characteristics and expressive force because of their scale structure, the relationship between modes and their different rhythms. The combination of mode and other expressive techniques can give music certain expressiveness and different styles. Therefore, the key determines the pitch, and the mode determines the alto, which is the tonic. For example, C major, A minor, Gongdiao and so on. All the above-mentioned are in C major, in which A minor and C major are relative tones, but the tonic is different, but the pitch is the same (C major tonic is 1, and A minor tonic is bass 6). If it is major, the relative minor is #f minor, which belongs to major (because the notation of staff is the same).