---
title: LED signaling
description: "| **Feature** | **Color** | **Explanation** | | --- | --- | --- | | Boiler | Green | **On**: Boiler demand active **Off:** Boiler demand inactive | | Pump | Green | **On**: pump demand active **Off**: pump demand…"
url: "https://faqdoc.info/en/systemauswahl/alpha-direct-en/alpha-direct-balance-base-station/led-signaling-2/"
updated: "2026-09-29"
category: Alpha direct Balance base station
---

# LED signaling

| **Feature** | **Color** | **Explanation** |
| --- | --- | --- |
| Boiler | Green | **On**: Boiler demand active **Off:** Boiler demand inactive |
| Pump | Green | **On**: pump demand active **Off**: pump demand inactive **Flashing**: Temperature limiter/dew point monitor active |
| Mains voltage | Green | **On:** Device in operation **Off**: Device out of service **Flashing:** Commissioning mode active |
| Fuse | Red | **On:** Fuse defective |
| Change over | Blue | **On:**Cooling mode active **Off:** Heating mode active |
| Heating zones (HZ) | Green | **On:** HZ active **Off:**HZ inactive **Flashing:** HZ active; No load balancing |