Installation and operating instructions for the Viessmann Vitotron 100 Type VMN3 and VLN3 electric instantaneous water boiler for central heating systems.
This manual provides installation and operating instructions for the Viessmann Vitotron 100, specifically models VMN3 (weather-compensated) and VLN3 (constant temperature). The appliance is a sealed unvented system boiler intended for domestic or semi-domestic use in central heating and DHW applications. It includes integrated components such as a circulation pump, safety valve, and diaphragm expansion vessel.
The document covers the entire lifecycle of the product, from preparation and assembly to electrical connection and commissioning. Key sections include detailed wiring diagrams for various power ratings (4–8 kW and 12–24 kW), descriptions of the internal Printed Circuit Boards (PCB MSK.80/04 and MSK.80/05), fault message interpretation, and a comprehensive spare parts list.
| Expansion vessel capacity | 5 litres |
|---|---|
| Maximum pressure | 0.3 MPa (3 bar) |
| Outlet temperature range | 20 – 85 °C |
| Maximum temperature | 100 °C |
| Dimensions (H x W x D) | 716 × 316 × 235 mm |
| Weight | ~20.5 kg |
| Boiler connections | G ¾" (female thread) |
| Expansion vessel pressure | 1.5 bar |
The Vitotron type VLN3 is set up for operation with a constant boiler water temperature, while the VMN3 is set up for weather-compensated operation.
No, these boilers are only intended for installation in sealed unvented heating systems.
The maximum permissible mains impedance is 0.27 Ω.