As the UK heating market increasingly adopts low-carbon technologies, installers are seeking solutions to maintain optimal cleanliness and water quality. A notable topic gaining momentum in the industry, especially with renewable systems, is the VDI2035 standard. This has long been the recognised standard in Germany for chemical-free filling alternatives, designed to prevent damage in heating installations caused by poor water quality, corrosion, and scale formation.
VDI2035 encourages proactive water treatment. Instead of trying to remedy poor water quality with chemicals after it has entered the system, installers treat the water beforehand. This removes scale and stabilises pH levels. To ensure proper functioning and a long service life, the quality of the filling water is crucial – hence the creation of the VDI2035 standard.
Water hardness is primarily determined by the concentration of calcium and magnesium salts. These minerals, known as hardeners, define the “total hardness” of water, measured in the VDI2035 standard in °dH (degrees of German hardness) or mol/ m³. One German degree of water hardness (1°dH) equates to 10mg of calcium oxide or 7.19mg of magnesium oxide per litre of water. Additionally, one millimole of calcium and magnesium ions corresponds to 100mg of calcium carbonate (CaCO₃).
For heating water, maintaining an alkaline pH between 8.2 and 10.0 is essential, as acidic water accelerates corrosion. The pH affects the protective surface layers on metals within the heating system, which serve as a natural barrier against corrosion. Aluminium components, such as heat exchangers and radiators, require a pH between 9.0 and 10.0 to avoid damage.
In UK domestic properties, the system is often filled via a filling loop or similar arrangement. Complying with water regulations is essential, requiring backflow protection to class 3 for domestic and class 4 for commercial settings. Isolators must be provided on both the potable and heating water sides of the filling loop, and the loop must be disconnected after use.
Permanent connection to the mains is only permitted if a CA device (domestic) or BA device (commercial, RPZ) is used. The demineralisation system must be installed downstream of the filling loop, leading to a complex, time-consuming installation.
Syr has simplified this process with the Filling Station 3228 All-in-One Connect. The All-in-One Connect ensures smooth and effective operation by providing automatic monitoring of filling and water conditioning, conductivity determination, special leakage protection, and an integrated RPZ valve for backflow protection up to fluid category 4.
Thanks to electronic monitoring and an integrated pressure reducing valve, the filling process stops once the desired system pressure has been reached. The filling frequencies are recorded and displayed in statistics. The initial system filling may also include the display of the total filling volume. The built-in leakage detection system will monitor the frequency of top ups to the system and the amount of water used. If this falls outside pre-set parameters alerts are triggered.
The 3228 All-in-One Connect is Wi-Fi-enabled and comes with a LAN connection. The SYR app can be used to create, monitor, check and control a project. For example, the smart valve informs installers/operators via push notification that the connected cartridge will soon be exhausted.
As renewable heating systems become increasingly popular, the chemical-free solution offers lower long-term maintenance costs, eliminating the need for chemical storage and disposal, and providing a more environmentally friendly system. www.syr.de/en