July 2025 — Prom-nasos.com.ua

Wet rotor pumps are a large group of pumps widely used in heating and cooling systems. Thanks to their silent operation, low energy consumption, and absence of mechanical seals, they occupy a significant niche both in industrial systems and residential heating installations. Currently, you can purchase basic options like single-speed pumps without any control, as well as “smart” electronic pumps with pressure and flow control and multiple operating modes. Despite all the advantages listed above, these pumps have one significant drawback — the quality of the water or heat carrier they work with. Regardless of the level of smart electronics involved, the core element of this type of pump equipment remains the mechanical part — the "wet rotor". Since the rotor is washed by the pumped medium, its quality must be adequate — clean, and free from mechanical impurities (scale, sand, rust flakes, etc.). The photo below shows a pump that was sent to us for servicing due to rotor jamming after just 1.5 months of operation. The impeller and the gap between the rotor and stator were clogged with rust flakes, which caused the rotor to seize. Conclusion — when using pumps of this type, it is crucial to ensure proper water treatment. With clean water, the pump will last well beyond the warranty period. Otherwise, you should consider pump systems that are less sensitive to water quality — such as inline dry rotor pumps equipped with a standard asynchronous motor and mechanical seal.