8 common problems in the installation of air source heat pumps
The vigorous development of "coal-to-electricity" in northern China has made the air source heat pump industry enthusiastic. However, in this context, there is one thing that air source heat pump manufacturers have to face up to, that is, the machine is sold, but no one will install it. At present, in the entire industry, there are very few professionals who know how to install. Irregular installation is an urgent problem to be solved. So, today, I will talk to you about the 8 common problems in the installation of "coal to electricity".Question 1: Insulation is not done well
Insulation is a very important part of the heating system. However, many manufacturers did not pay much attention to the "coal to electricity conversion" this time. The insulation is poor and the pipes are basically not insulated. Many houses in Beijing’s rural areas are not insulated, so heat dissipation will be very strong. It may be okay when the temperature is relatively high, and it is hard to say whether the temperature can rise after entering the real low temperature.
It is particularly worth reminding that the location of the external refrigerant interface is very critical and must be insulated, but basically no air source heat pump manufacturer has noticed this. For the split machine, the highest temperature is at the interface of the refrigerant. If heat preservation is not done, the copper head of the refrigerant interface will dissipate very quickly in a low temperature environment, and the heat loss will be great.
Question 2: Many drainage problems
Drainage is a big problem in northern China. Unlike southern China, it doesn’t matter that the running water does not matter. The temperature in the north is very low after three or nine days. The water after defrosting will freeze soon, and the ice will “climb”. It may freeze the host. In terms of safety hazards, some hosts are installed on the side of the road, and the defrosted water flows directly onto the road, which is very slippery after freezing and is prone to accidents.
In addition, most of the “coal-to-electricity” installations are air source heat pump split units. When many manufacturers install the copper pipes and electric pipes directly through the wall, if there is rain, it will flow directly along the pipeline. Inside the mainframe, if the temperature is low, the mainframe may be frozen. In the correct way, the copper pipe should take a detour and pass through the wall.
Problem 3: The pipe diameter is too small and the resistance is large
The pipe diameter of the pipeline is a big problem. The original pipes are connected to coal furnaces. The water temperature is very high and the pipe diameter is not large. Many air source heat pump manufacturers have connected pipes that are too small. The pipes of users’ homes are all DN32 or DN40 galvanized pipes. The 32 and 40 refer to the inner diameter, but now air source heat pump manufacturers use the same size. PPR tube, and this data refers to the outer diameter. Compared with the original pipeline, it is much smaller, and the result is insufficient water flow.
In addition, many air source heat pump manufacturers use 90-degree elbows instead of 45-degree elbows, and the water resistance is very large. If the temperature does not rise in the later period, a big possibility is the low flow rate.
Question 4: There is a problem with the host installation
There are two main problems with the installation of the air source heat pump host. One is relatively short, and some are even directly cushioned with red bricks. If the defrosting water is not drained, there will be great hidden dangers; the other is that the feet are too small, Beijing, China Many walls in rural areas are red bricks or lightweight bricks. If the external machine is hung on the wall and the weight of two to three hundred catties is pressed down, it will become crooked over time.
In addition, grounding is a mess. The houses built in rural areas in northern China are not grounded, and the steel is very shallow, usually at least 80-100cm, but many of them are not done. The wiring is also not securely connected. It is best to use the pressure plate screw to lock, but many are very irregular. If something goes wrong in this respect, it will be very serious.
Question 5: There are many and complicated valves
Another problem is that the valves of the air source heat pump system are not well done. The pressure gauge, temperature gauge, gas tank, filter valve, ball valve, etc. are all separated. There are many hidden dangers. In fact, there is a kind of multi-functional integrated valve that all valve parts are assembled together. Although the price is more expensive, it can save a lot of things and there are no safety risks.
90-95% of the installed PPR pipes are used this time. All the valve parts, as well as the head fittings connected at both ends of the PPR pipe, add up to a high price. Moreover, the more joints, the greater the risk of water leakage. If you use an integrated valve, you can add accessories at both ends, which is very convenient and has fewer hidden dangers.
Question 6: Did not consider drainage
The radiators made by the “Coal-to-Electricity” project in Beijing, China are all open systems and need to be filled with water, which means a lot of dust or dirt. But many are not equipped with a drain valve, or the drain valve is installed incorrectly.
It is very important to make heating and drainage valves in northern China. In case of a power failure, ensure that the water can be drained clean. Therefore, the drain valve must be installed at the lowest point. This is an important point, but many air source heat pump manufacturers have not done it, or have not done it, and have no such awareness at all. If there is a problem with the host this winter, it is estimated that many of them will be frozen out.
Question 7: Improper installation location enhances noise
In addition, noise is also a big problem. Some air source heat pump products have problems in design, and there are more problems in installation. If the installation is not horizontal and vertical, the noise will be loud. There is also the choice of installation location. Some are due to the requirements of the owner, but as the installer, it is necessary to communicate and coordinate with the user, but many are not explained because they are not professional. Some are installed in the alleys, and some are installed in the corners, which easily resonate. Especially at night, the feeling of noise will be more obvious.
Question 8: Inaccurate temperature control probe
Many temperature probes are very problematic. Most of them are made of temperature-controlled backwater, and the probe is directly tied to the iron pipe of the backwater, but everyone has not wrapped it for insulation, just wrap it with tape twice.
Generally speaking, the correct approach should be to tie it to the return water valve, the valve is made of copper, the heat transfer will be more accurate, and then wrap the insulation cotton. If there is no place to tie it to the iron pipe, it must be wrapped with insulation cotton for insulation, otherwise the measured temperature will be inaccurate. The consequence of this is that the air source heat pump unit will not stop at all and it has been working.
When the wave of coal-to-electricity changes recedes and the post-coal-to-electricity era is approaching, where will the Chinese air-source heat pump manufacturers go? Let us wait and see