/ DRAIN BACK systemThe DRAIN BACK system by Hewalex is a proven technology with our own design. Perfect for regions with very high solar radiation, our DRAIN BACK system is completely resistant against overheating thanks to the operation of the pump unit and the expansion vessel. The system is protected by a specially designed glycol tank mounted directly to the collector. The tank has been engineered for efficient operation with two KS 2600F TLP AC collectors, with a total surface area of 5.2 m².
Ideally suited for single-family homes occupied by 3–4 people, as well as for small commercial buildings. | Easy to install on a sloped roof, flat roof, ground-mounted structure or building façade. | Free monitoring system with the MiniSOL app.
Choose between system DB-A, in which the hot water tank is installed in the technical room of the building and system DB-B, which is installed entirely on the roof and is an alternative to a thermosiphon system.
Location of the DRAIN BACK system tank in our design
In our solution, the DRAIN BACK system tank is located below the solar collectors in both, DB-A and DB-B.
The advantages:
- Flexible piping layout – the piping can even run above the collectors, and the system will still drain correctly. The pipes remain filled with glycol.
- Standard solar pump – there’s no need for expensive high-lift pumps. A simple, standard pump is sufficient, reducing installation and operation costs.
- Quiet operation inside the building – no sounds of liquid flowing are heard indoors. The flow is interrupted only in the tank located on the roof.
- Faster filling and draining of collectors during operation – thanks to placing the tank closer to the collectors, the process takes a maximum of 40 seconds, regardless of installation size – much quicker than in standard solutions.
What makes DRAIN BACK DB-B different from a thermosiphon?
Corrosion protection – Complete filling of the space between the jacket and the tank with liquid (without an air pocket) protects the steel against corrosion and extends the lifetime of the system.
Less scale deposits – Lower heating temperatures reduce the precipitation of calcium and magnesium carbonate. This keeps heat exchange efficient and ensures trouble-free operation of fittings.
Easier installation and aesthetics – The water heater mounted under the collectors simplifies installation work and improves roof aesthetics, with fewer elements visible from the outside.