Decoration hardcore popular science series-guide to selection and installation of floor heating

Every winter, I will think of the classic joke: you eat popsicles with the heating on in the north, and I am shivering in the rainy south.

Now more and more places in the south are considering floor heating. If you have this demand, this article is worth reading. If not, it can also be used as a knowledge reserve.

Of the three houses renovated on 20 17, the one occupied by oneself has floor heating, and just half of them belong to the decoration industry. If you are interested, you can read the article written earlier.

I bought floor heating and ran a lot of floor heating companies. Due to the limited budget, I originally planned to buy materials and install them myself, so I made up a lot of things about floor heating, from materials to installation and debugging. Later, I found a new local floor heating company and installed the whole house floor heating, and the price was relatively low (fifteen thousand). I also became good friends with my boss (later I recommended many clients to him, which is another story).

2 Definition and classification of floor heating

Floor heating is short for radiant floor heating. In the 1950s, it became popular in Europe and North America. It is a heating method in which a heat source (coil or heating wire) is evenly buried under the concrete to heat the ground and radiate heat indoors.

Its history can be traced back to Roman times, when hot springs were introduced into underground pipelines to heat the ground circularly. There were similar designs in ancient China. In the palace, the heating flue is laid on the ground for heating through clever design.

At present, there are three main types of floor heating in the market: electric floor heating, water heating system and air energy floor heating.

(1) electric floor heating

Taking electricity as energy source, electric energy is directly converted into heat energy by using heating cable (now with heating film), which is mainly composed of ground insulation material, heating cable, temperature controller and so on.

Advantages: simple structure and installation, basically maintenance-free.

Disadvantages: the relevant domestic technical specifications and standards are not perfect, the quality of heating cables is uneven, and the domestic maturity is not high. The use cost of ladder power consumption area is high.

(2) Circulation system

Taking natural gas as energy source, the natural gas burns the water in the heating coil through the wall-hung boiler, and then circulates the hot water to the floor heating pipe for radiant heating through the water diversion valve and the temperature controller.

Advantages: high maturity, high market share and no step gas consumption.

Disadvantages: the process is more complicated than electric floor heating, and there are many accessories such as wall-hung boilers and water diversion valves, which need regular maintenance.

(3) air energy floor heating (heat pump floor heating)

Strictly speaking, air energy floor heating is also a kind of water heating, which is different from using natural gas as a heat source. It uses the heat energy in the air, and the water in the heating coil is converted by the compressor to achieve the heating condition (a bit like the principle of air conditioning). You don't need a wall-hung boiler, you need an air energy host (heat pump), and you need electricity.

Advantages: energy saving and environmental protection. Compared with electric floor heating and circulating system, it saves a lot of money. Selected as the key recommended project of national energy saving plan.

Disadvantages: The pre-installation cost is high (generally more than 40,000 yuan is needed locally), the system is complex, and the maintenance is difficult. The permeability is not high (only in recent years 10), and the thermal efficiency will be low when the outdoor temperature is low in winter. The mainframe takes up a lot of space.

The three methods of floor heating have their own advantages and disadvantages. Can be purchased according to the actual situation of the individual. Where the electricity price is cheap and there is no ladder electricity price, you can choose to buy electricity and floor heating. Where natural gas is cheap, you can buy a circulating system, and if the heating area at home is large, you can buy air energy (more energy-saving than electric floor heating).

Personal recommendation circulation system, mature and reliable, convenient for later maintenance. The comprehensive cost is not high, considering the domestic hot water.

3 Precautions for the purchase and installation of circulating system

(1) wall-hung boiler

Boiler, commonly known as boiler, is the most important and expensive part of liquid circulation system. It burns natural gas to heat water to generate heat (heated to 35 ~ 85℃), and sends the hot water to the distribution manifold to heat each loop through the built-in circulating pump. The quality and efficiency of wall-hung boiler directly affect the later use cost.

The mainstream imported wall-hung boilers are basically monopolized by Germany, such as the three giants of wall-hung boilers: Weineng (Germany), Bosch (Germany) and wiesmann (Germany).

In addition, the Italian departments of Beretta, ariston and Yima have a good reputation in the market, as well as the British Baxi.

Finally, there are domestic squirrels, Haier, Wanhe, Midea and so on.

Take the 24kw power wall-hung boiler as an example. It is a pure imported boiler 1w (condensing boiler 1w5 or above), and some parts are imported and assembled at home for 7 ~ 8K and about 5k.

For example, my Bosch Geshi 7000 is made in Shanghai.

The nominal thermal efficiency is about 93%. Key components such as water pump and air valve are imported, and the rest are made in China.

In addition, the thermal efficiency of a good condenser can reach about 104%, so if the heating area is large, the condenser can be considered, and the difference cost will come back in a few years.

Household cookers with limited budget can be considered. Personally recommend pure import or joint venture domestic.

(2) Distribution manifold

As the control center of the liquid circulation system, the wall-hung boiler is only responsible for sending hot water to the distribution header, and the specific distribution and control are controlled by the distribution header. According to the floor heating circuit, there are 4 companies, 6 companies and 8 companies in the distribution manager. By using temperature controller and solenoid valve, the temperature of each loop can be controlled independently.

The distribution manifold is generally made of pure copper, and its service life exceeds 10 years.

▲ Working principle: According to the solenoid valve, the ejector pin is controlled to press down and lift up, so as to open and close the loop, thus controlling the room temperature of the loop.

The mainstream brands in the market are: Manruide, Owen Top, Danfoss, Aikangbaoli, Guangfa, Rifeng and so on.

Take a set of 6-loop distribution manifolds as an example. Imported brands often need more than 65,438+0,500, while domestic brands only need about half the price. Distribution manifolds without temperature control and manual control are cheaper.

Rifeng manual switch distribution manifold around 600 yuan.

The advantage of manual operation is that it is cheap, the result is simple and not easy to break, and the disadvantage is that it can't accurately control the temperature, so not many people use it now.

(3) floor heating coil

The mainstream floor heating coils in the market are as follows:

PB tube: high temperature resistance, good oxygen permeability resistance, hot melting, pressure resistance and high price.

Representative brand: George Fisher

PE-X tube series: PE-X series includes PE-XA, PE-B and PE-XC, which are distinguished according to the above production methods. The performance is similar. A series is the earliest, and C series is the latest, with better environmental protection and flexibility. At present, it is widely used in China, with good heat and pressure resistance and good flexibility. The disadvantage is that it can't be hot melted. The price is cheap.

Representative brands: Rifeng, Aikangbaoli, Owen Top, Ruihao, etc.

PE-RT tube: the performance is basically the same as that of PE-X series, but it is cheaper, more flexible and can be hot-melted. There are two kinds of raw materials, PERT 1 and PERT2. 1 generation is widely used in China, with high temperature resistance of 70 degrees, and the second generation has high temperature resistance of 90 degrees.

Representative brands: Rifeng, Jinniu, Wei Xing, Tairi, George, etc.

PE-X series and PE-RT pipes occupy the bulk of the domestic floor heating market, so it is very important to distinguish the oxygen permeability of materials when purchasing (foreign standards are mandatory).

The price ranges from one meter in 4 yuan to one meter in 20 yuan, which is above the domestic mainstream brand 6 yuan and above the import 15.

(4) Thermal insulation materials

The composite insulation layer in the above picture is mainly composed of extruded board, reflective film and expansion belt.

Among them, extruded board is particularly important. A good extruded board is resistant to compression and heat, and has a good thermal insulation coefficient. When purchasing, the whiteboard is preferred. Press by hand. If you can easily squeeze out a pit, it is often a substandard product. The extruded boards of regular manufacturers in the market will be marked with thermal insulation coefficient, and the density of excellent extruded boards is often above 35kg/ m3. You can ask the floor heating company or manufacturer when purchasing.

The price of extruded board ranges from 200 to 800 cubic meters. It is recommended to buy at least 400 cubic meters.

(5) Temperature control panel and control solenoid valve

The temperature control panel and solenoid valve are the actuators to control the opening and closing of the distribution manifold circuit, and they are also important components to control the room temperature.

Temperature control panel

LCD panel electronic thermostat (with program control) is the mainstream in the market, and Manred, Sunwell, Danvers (more expensive), Siemens, Honeywell and Hailin have higher market share.

Solenoid valve (thermoelectric valve) for floor heating and temperature control

A good thermostat temperature probe only uses imported components, and the temperature deviation is small. It is recommended to buy it together with the solenoid valve of the actuator. For example, Manfred's temperature control panel and solenoid valve, 380 yuan.

(6) Radiator assembly

According to the materials, it can be divided into the following categories.

Cast iron radiator: large volume, occupying space, basically eliminated.

Copper-aluminum composite radiator: one of the mainstream, with light weight, corrosion resistance, fast heat dissipation and high price.

Aluminum radiator: cheap and fast, afraid of corrosion and water leakage.

Pure copper radiator: good effect, the highest price and less consumption.

Low carbon steel radiator: low price, good heat preservation, pressure resistance and corrosion resistance, and less use.

Steel radiator: affordable, good heat dissipation effect, no obvious short board, and certain requirements for water quality.

The copper-aluminum composite radiator and steel radiator are the most widely used in the market, and the mainstream brands are St. Lawrence, Sende, Nuoluo and so on.

Household floor heating radiators are generally copper-aluminum composite radiators with specifications of 75*75, 80*80, 1 16*60.

Matters needing attention in installation and construction of floor heating:

(1) Waterways and circuits related to floor heating should be reserved during hydropower construction.

(2) Before construction, the insulation layer and the coil should be cleaned, and the ground should be cleaned to ensure that the ground is flat and clean.

(3) The extruded board shall be laid as a whole as far as possible, and the joints shall be sealed and insulated with aluminum foil tape.

(4) The coil can only be wound after the reflective film is laid.

(5) Each coil should not exceed 100 m, and 60 ~ 80 m is appropriate, too long will reduce the thermal efficiency.

(6) Before backfilling, a pressure test (about 6kg pressure) must be carried out to ensure that there is no leakage before backfilling.

(7) Pea stone concrete or coarse sand concrete must be used for backfilling, and fine sand is not allowed.

(8) When backfilling, pay special attention not to damage the coil, do not wear pointed tools, and wear flat shoes.

(9) The distribution main is recommended to be installed in the bathroom. In case of water leakage, it will not affect other areas.

Distribution manifold in bathroom

(10) During debugging, the temperature should be gradually increased, and the wall-hung boiler should be controlled below 55 degrees each time. If the temperature is too high, the water in the coil is easy to scale.

During installation and commissioning.

4 abstract

Floor heating is a systematic project, involving water, electricity and electricity. Problems in any aspect may lead to abnormal use. Friends who need this in decoration suggest learning more basic knowledge and comparing more before buying floor heating, so as to go to the site to check during construction and find problems in time. Avoid losses in later use and so on.

Some pictures come from the internet. If there is any infringement, please contact.

This answer comes from the user's iron head 32 1. For more decoration strategies and home experience, welcome to visit the live APP.