Heat transfer medium propylene glycol for heating systems

Propylene glycol for heating systems is made from petroleum products, has excellent performance characteristics and can be used as a working fluid. This substance, when frozen from the liquid phase, transforms into a gel-like state, which makes it possible to protect the pipelines from corrosion and rupture.

Features of the water system

In our country, the most widespread water heating system, in which the transfer of energy is from the source to the heating devices by means of a liquid coolant, which is usually water. It is worth noting that it is the best way to handle the heat transfer function. However, it has a unique drawback - when frozen, this coolant expands, crushing radiators from within and damaging the cast iron and steel systems. Ice congestion that is formed in pipelines with local freezing is less dangerous, but they are also capable of delivering many problems and leading to local overheating or even boiling of the coolant.

This moment explains the high interest of owners of autonomous heating systems and heat engineers to antifreeze, which can replace water, affordable and safe for human health and life. It's not a secret that even in the most reliable system faults and leaks are not excluded.

Among such liquids, it is necessary to allocate antifreeze on the basis of propylene glycol for heating systems.

Propylene glycol

This coolant is a colorless viscous liquid, which is characterized by a sweetish taste and a corresponding odor. And most importantly, it is safe for human health. Propylene glycol has become widespread in various sectors of the national economy, including the cosmetic and food industries.

Propylene glycol for heating systems has all the properties of an ideal heat carrier: it boils at a temperature of 187 ° C, and crystallizes at -60 ° C.

Another advantage of propylene glycol is low corrosion activity, which allows to reduce the bar of requirements for the quality of steel for heating systems and, consequently, to reduce their cost.

Propylene glycol is excellent for systems including structural elements made of rubber, polymeric materials, aluminum, copper, iron and steel. In addition, when this substance is used on the inner surface of the heating system, scale and precipitation are not formed, which ensures high heat transfer and increases the operating life.

Properties

Propylene glycol has the following properties:

• Good hygroscopicity;
• At any percentage, propylene glycol is completely soluble in water;
• This substance is non-toxic;
• Excellent bactericidal and sterilizing properties;
• Low volatility;
• Protection of the system against corrosion and freezing.

In addition, propylene glycol for heating systems can withstand high temperatures.

Specifications

They have the following propylene glycol:

• Transparent (colorless);
• Boiling point at atmospheric pressure of 188.2 ° C;
• At a temperature of 20 ° C, a density of 70% solution of 1,044 g / cm ³ ;
• The beginning of crystallization of 70% solution - at a temperature of -67 ° C;
• The operating temperature is in the range of -40 ° C to +108 ° C.

Advantages

The first advantage of antifreeze, due to which it received such a name, is the property not to freeze at large minus temperatures, which the coolant in question has. Propylene glycol for the heating system forms an amorphous structure, this is what distinguishes it from water. This substance does not increase in volume, accordingly, the destruction of the heating system as a result of this does not threaten.

disadvantages

Unlike water, propylene glycol for heating systems has a lower heat capacity. Hence, it accumulates less heat and, consequently, gives it less. As a result, consumers will need more powerful heaters.

The viscosity of the antifreeze is 4 to 5 times higher than that of water. For this reason, the intensity of circulation of propylene glycol through the system will be less. Choosing heat carriers for heating systems based on propylene glycol, you need to consider these factors.

Application

Before pouring into the heating system of the non-freezing liquid, it is necessary to perform hydraulic tests.

The correct choice of antifreeze deserves special attention, it is important to choose one that will fully comply with the heating system. For these purposes, an analysis of its elements is made, as well as the materials from which it is composed. After that, antifreeze is selected, which will not contain additives hazardous for the materials of the system.

For heating systems, the most popular is the non-freezing liquid with carboxylate additives. As a rule, it is used for at least 5 years. It is also worth noting that the heat transfer medium propylene glycol for a heating system without effective additives is especially dangerous for copper heat exchangers and may lead to their unfitness after a year of operation.

During use, the coolant becomes contaminated, so its quality requires constant monitoring, which is desirable to produce in the laboratory.

Antifreeze propylene glycol for heating systems should be replaced only after a hydraulic test of the system and washing it with an alkaline solution.

Effective use

To effectively use this non-freezing liquid, it should be poured into the heating circuit after thoroughly sealing all components and performing hydraulic tests. The system itself is recommended to be supplemented with a circulation pump.

By changing the propylene glycol solution for heating systems as a percentage, a liquid with a freezing point of -1 ° C to -65 ° C can be obtained.

The life of propylene glycol without additives is on average 5 years, then in the ventilation, cooling or heating system, it is necessary to either rinse using an alkaline solution or completely replace the liquid. With prolonged or frequent exposure to low temperatures (for example, the heating system was not used for a long time in winter), it is preferable to change the solution every 3 years.

Washing

The heating system requires periodic washing. Various liquids are used for these purposes. Washing at home is usually done by water.

To get a good result, the system should be filled for about an hour with a solution of caustic soda, which perfectly fights against corrosion and scale.

Another important point is to know what freezing temperature of antifreeze is needed. Only when this condition is fulfilled, it is possible to choose the most optimal liquid for heating systems. Propylene glycol has several advantages over conventional water. And the main thing is the ability not to freeze at low temperatures.

After filling the antifreeze in the heating system, you can not worry about what will happen "defrosting" the heating appliances in the country house. Do not have to go there constantly to check the status of the system.

Various additives give the best quality to the non-freezing liquid. As a result, the heating system will last longer. Additives can protect metal surfaces from corrosion, while preventing the destruction of sealing elements.

How to choose antifreeze

To date, the construction market offers a wide range of coolants, the basis of which is propylene glycol for heating systems (reviews about them are mostly positive). All of them have a different cost, which directly depends on the brand, the country of origin, as well as the performance characteristics of the solution itself.

Some consumers, without special knowledge, use automotive antifreezes in their heating systems (transformer oil, antifreeze, etc.). However, this is unacceptable, since such solutions contain unsafe for human health and flammable substances. The most optimal and universal in use is a non-freezing liquid based on propylene glycol. When choosing a coolant for a heating system, you should pay attention to the following points:

• Shelf life. In the original packaging, antifreeze can be stored for a long time (even if the period is unlimited, it must in any case be specified by the manufacturer).
• Terms of Use. Non-freezing liquid can be universal, and can only approach a certain type of equipment.
• Packing material. As a rule, the antifreeze liquid is sold in cans of plastic. In a galvanized container this substance loses its operational properties.
• Certificate of quality. Non-freezing liquid must be manufactured in accordance with technological rules and norms, tested in laboratory conditions and allowed for sale.
• Presence in the composition of refined products.

It is very important to use antifreeze strictly according to its purpose. Neglecting the rules for choosing a non-freezing liquid will lead to negative consequences - emergency situations, hydraulic shocks, pipeline rushes, etc.