Brazed Plate Heat Exchanger Installation Considerations

In the design and construction process of the air conditioning industry, it is popular to say that "three parts of the product and seven parts of the installation", which shows the importance of the installation for the project. Even as a spare part of the brazed plate heat exchanger, its installation for the performance of the machine is not to be underestimated, any improper operation of the installation process may reduce the heat transfer efficiency and service life of the brazed plate heat exchanger, which in turn brings immeasurable risks to the whole machine customers in terms of cost, maintenance, and terminal experience.

Here is the content list:

• Installation process considerations

• Precautions for the brazing process

• Frost protection

Installation process considerations

Brazed plate heat exchangers should not be installed where there are strong vibrations, circulating pressures, or large temperature variations. It is important to ensure that no vibrations and stresses are transmitted to the heat exchanger. If there is such a risk, vibration-damping devices should be added. For heat exchangers with large pipe connections, it is recommended to add cushioning devices in the piping. It is also recommended to use a rubber cushion between the brazed plate heat exchanger and the fixed clamp as a cushion. In single-phase applications (meaning that no phase change of the fluid occurs), such as water-water heat exchange, and water-oil heat exchange, the installation orientation has little or no effect on the performance of the heat exchanger. However, in two-phase applications (where the fluid undergoes a phase change), the orientation of the heat exchanger becomes very important.

Precautions for the brazing process

Degrease and polish the surface. Apply flux, insert the copper tube into the joint and hold it in place, and braze with silver solder containing at least 45% silver at a maximum temperature of 650ºC (1200ºF). Do not aim the flame directly at the brazed plate heat exchanger. Use a damp cloth to cool the brazed plate heat exchanger to prevent it from overheating. Protect the inside of the brazed plate heat exchanger with nitrogen gas to prevent oxidation. Another point to note is that overheating can melt the copper solder and damage the brazed plate heat exchanger!

Frost protection

The anti-freeze treatment of the heat exchanger is also very important. A filter can be installed upstream of the brazed plate heat exchanger to prevent the brazed plate heat exchanger from clogging. When the evaporating temperature is close to the freezing point of the liquid on the cooling side, anti-freeze measures are required. Use an anti-freeze thermostat and flow switch to ensure a constant water flow before, during, and after compressor operation. Another small point to note is that after starting the system, wait a few moments before starting the condenser or wait until the flow through it decreases before starting the condenser.

These are some of the considerations for brazed plate heat exchangers during installation and use. These issues are not only found in the installation of air conditioners, but also in many other areas. We hope that these precautions will help you and give you a better understanding of heat exchangers.