Chemical raw materials
and materials

Heat transfer fluid for solar systems

We, as manufacturers of FRREEZLIGHT antifreezes and coolants, often face the question of what kind of coolant should be bought for solar systems or solar collectors. Undoubtedly, when choosing any coolant, you should adhere to the following principles:< /strong>

  1. Compliance of the coolant with the technical characteristics of the heating or cooling system
  2. Security
  3. Longevity
  4. Anti-corrosion
  5. Antiscale
  6. Temperatures
  7. Verified manufacturer.

These are general rules when choosing any coolant or coolant. However, when choosing a coolant for a solar system and, in general, when buying it, it is necessary to take into account a little more technical features of the latter.
First of all, when choosing a solar installation, it is recommended to check what protection against boiling and excessive pressure is in this installation. Perhaps this system is equipped with a controller. Namely, the overpressure and temperature valve. The presence of such a KIDT controller will provide you with a “quiet life”, as it provides control of the pressure and temperature of the coolant in the system, preventing overheating. Such a valve automatically relieves excess pressure (max allowable pressure in the system (5 atm.) and discharges hot water (steam) when the temperature reaches 98°C.
Also, to increase the safety of the system, expansion membrane tanks, a safety valve for steam release or modern mechanisms such as “AuroStep” can be used. All these methods will help to avoid stagnation in the system, its unwanted breakdowns and, moreover, increase the stability and increase the durability of the coolant.
It is very important to correctly design and calculate the operating conditions of the solar battery system and take into account climatic features. Indeed, one of the advantages of modern solar systems is their all-weather operation, therefore, not water is used as a heat carrier for such systems, but a special non-freezing liquid based on glycol with a high boiling point.

Best to use propylene glycol based heat transfer agent</ a> and distilled water, which does not contain nitrites, phosphates and borates and is safe for humans and the environment. The proportion of propylene glycol and water for such a coolant, recommended by manufacturers of solar installations, averages 45% glycol and 55% water.

The coolant of our production FREEZLIGHT -32°C for solar systems is a safe non-freezing liquid based on propylene glycol. In addition, this coolant contains < strong>distilled water, European quality anti-corrosion and anti-foam additives and dye.< /span>

Heat media for solar panels tm FREEZLIGHT fully meet the requirements DIN 4757 part 3 for solar systems, their production is approved by the international certificate ISO 9001.

I would like to pay attention to the issue of stagnation and, as a result, boiling of non-freezing liquid in the solar system.

So what is the boiling point of the coolant?

There is a rule – the higher the pressure in the system, the higher the boiling point of the coolant becomes.

Given that the maximum allowable pressure is up to 5 atmospheres, we calculate:
The boiling point of the coolant at a pressure of 2 atmospheres is 126-128˚С. At a pressure of 3 atmospheres, the coolant will boil at a temperature of about 140˚С, and at 4 atmospheres – about 150˚С.

The benefits of using “FREEZLIGHT” for solar systems:

  1. Does not freeze unlike water at low temperatures
  2. Works well in stagnation.
  3. The concentrate withstands temperatures ranging from -60 to +188-190°С
  4. Protection against scale and corrosion
  5. Safe for all system elements, including rubber seals
  6. Safety for humans and the environment
  7. Low viscosity and easy to overclock
  8. 5 year quality guarantee

FREEZLIGHT anti-freeze fluid with a package of anti-corrosion additives from the best European manufacturers – 100% protection against freezing and corrosion in the system.

However, the heating fluid in the solar system should be checked regularly. Typically, manufacturers of solar installations recommend doing this once a year. Such an event is necessary to check and maintain the declared temperature of the coolant, to study the stability of its physical and chemical properties, and, accordingly, the possibility of further use.
We, as manufacturers of heat transfer fluids, do such an analysis in our production laboratory for our customers absolutely free of charge. You can also conduct mini analytics yourself. For this you need:

  • drain a small amount of coolant from the system (1-1.5l)
  • check its organoleptic properties (color, consistency, uniformity)
  • measure the pH of the solution using indicator strips (pH must be at least 7 units)

If the quality of the coolant does not meet the norm, it should be replaced.