Our range of products for bivalent cooling and heating water treatment
Water is the key factor in ensuring the trouble-free operation and longevity of heating and cooling systems. The specifications set out in VDI 2035, VDI 6044, ÖNORM H 5195-1 and SWKI BT 102-01 form the basis for installation, filling and maintenance.
As it flows through the system, the water comes into contact with almost all components and can – in both heating and cooling circuits – have a significant impact on function, efficiency and service life. Without targeted treatment, there is a risk of corrosion, deposits and other system-related damage.
Against this backdrop, UWS continuously develops practical and efficient water treatment solutions that are consistently designed for use in compliance with guidelines. The aim is to reliably protect heating and cooling systems and ensure consistently stable operation.
The product range extends from initial filling and controlled top-up to magnetite separation and corrosion monitoring. UWS treatment units enable effective water treatment using the bypass process, which combines softening, desalination and filtration in a single step.
Fully demineralized water with mixed bed resin Vadion pH-Control
In order to meet the values recommended in VDI 2035 (hardness of 0.3 °dH, conductivity ≤ 100 μS/cm and a pH value of 8.2 – 10.0 in stainless steel systems or 8.2 – 9.0 for aluminum components) and VDI 6044, we have developed our mixed bed resin Vadion pH-Control has been developed. In addition to desalinating the water to < 100 µS/ cm, it also ensures that the pH value of the filling water is within the required range. The application range is in a temperature range from 3 °C to 80 °C. This also makes it possible to remove existing residual hardness and dissolved salts in the heating water of a heating system during operation (bypass process)
Why Heating water treatment?
Stone formation, corrosion and magnetite are frequent causes of damage in the event of problems with the heating system. The VDI 2035 specifies guide values for the heating water for these reasons. These form the basis of many warranty conditions – which planners, installers and operators should always keep in mind. If the specified guidelines are not adhered to, there is a risk of:
- Refusal of commissioning by the manufacturer
- Refusal of the warranty claim in the event of damage and
- Performance and efficiency losses
- Medium/long-term damage to the system.
Why Cooling water treatment?
Scaling, corrosion and magnetite are common causes of damage in the event of problems with the system. For these reasons, VDI 6044, ÖNORM H 5195-3 and SWKI BT 102-01 specify guide values for the cooling water. These form the basis of many warranty conditions – which planners, installers and operators should always keep in mind. If the specified guidelines are not adhered to, there is a risk of:
- Refusal of commissioning by the manufacturer
- Refusal of the warranty claim in the event of damage and
- Performance and efficiency losses
- Medium/long-term damage to the system.
The standards VDI 2035, VDI 6044, ÖNORM H 5195-1, SWKI BT 102-1
The core objective of VDI 2035 is to prevent limescale formation and water-induced corrosion in heating systems. EN 1717 sets out requirements for protecting drinking water from contamination by non-potable water, and in accordance with EN 14336, heating systems must be flushed prior to commissioning.
VDI 6044 applies additionally to cooling and chilled water systems. Its focus is on preventing damage in cooling circuits, particularly due to corrosion, deposits and microbiological growth. It thus applies the fundamental principles of water treatment to cooling applications, whilst taking into account the specific requirements of these systems.
In other European countries, different standards may apply. In Austria, for example, it is ÖNORM H 5195-1, and in Switzerland, SWKI BT 102-01. However, many countries now follow VDI 2035.
FAQ - Cooling and heating water treatment
The values recommended by VDI 2035, ÖNORM H 5195-1 and SWKI BT 102-01 are a hardness of 0.3 °dH, conductivity ≤ 100 μS/cm and a pH value of 8.2 – 10.0 in stainless steel systems and 8.2 – 9.0 for aluminium components.
The heating water should be limescale-free, corrosion-free, clean and clear in accordance with the applicable standards. It should also not have an unpleasant odour.
If there are too many anions and cations in the water, it must be demineralised. Desalination removes several salts (cations and anions) from the water, which trigger corrosive and decomposing reactions in the heating system. In turn, desalination prevents scale formation, as calcium and magnesium are also removed. This reduces conductivity enormously as (almost) all cations and anions and therefore conductive salts are removed.
The advantages of low conductivity and therefore demineralisation:
– The lower the conductivity, the higher the heat capacity
– Higher tolerable oxygen concentration
– Significantly reduced likelihood of corrosion
– Specifications of all manufacturers are met
The standards differentiate between low-salt and high-salt operating modes. For low-salt heating water, a conductivity of > 10 to ≤ 100 µS/cm applies; high-salt heating water should be > 100 to ≤ 1,500 µS/cm.
The higher the conductivity in the water, the greater the likelihood of corrosion. The salts dissolved in the water largely determine the conductivity. A high salt content causes high conductivity. Oxygen binding agents and corrosion inhibitors also increase conductivity. Electrochemical corrosion only takes place if the installed materials come into contact with an electrically conductive medium. Conversely, this means that low conductivity reduces or slows down corrosion in the heating system.
In order to fulfil the values recommended in VDI 2035, there are special mixed bed resins (ion exchangers). The UWS Vadion pH-Control not only desalinates the water to < 100 µS/ cm (corresponds to 0-2 °dH), but also ensures that the pH value of the filling water is within the required range. The application range lies within a temperature range of 3 °C to 80 °C. This also enables the removal of existing residual hardness and dissolved salts in the heating water of a heating system during operation (bypass process). With our treatment devices, you fulfil all manufacturer specifications.
VDI 6044 relates to the prevention of damage in cold-water and cooling circuits.
It supplements VDI 2035 for open and closed systems with and
without antifreeze, with a capacity of at least 1,000 litres and a circuit temperature
below 40˚C.
The guideline provides guidance on the planning, installation and operation of
new and existing systems.