iT500 Gateway – Red LED Keeps Flashing and No Internet Connection

iT500 Gateway – Red LED Keeps Flashing and No Internet Connection

If the iTG500 gateway is flashing red continuously, it indicates that the unit is not connected to the Internet or can’t reach Salus servers. Below you’ll find troubleshooting steps to fix this and restore proper function.


1. What does the flashing red LED mean?
  1. πŸ”΄ Flashing red LED – No internet connection.
  2. 🟒 Solid green LED – Gateway is online and connected to the Salus server.


2. Check LAN cable and network
  1. Confirm the LAN cable is securely connected between the router and gateway.
  2. Test a different port or cable if needed.
  3. Make sure other devices in the same network are working.

3. Router compatibility – a common issue
​

Newer routers (e.g. from Virgin, BT, E.E., FritzBox) often support only 100 Mbps or faster, but iTG500 operates at 10 Mbps.


Solution: Use an Ethernet switch between router and gateway to force backward compatibility.



4. Restart gateway and thermostat

  1. Log out from the iT500 Plus app.
  2. Disconnect power and Ethernet from gateway.
  3. Place thermostat close to the gateway.
  4. Remove batteries from thermostat for 15 sec.
  5. Reconnect gateway to power and LAN.
  6. Wait for LED to change to green.
  7. Reinsert thermostat batteries.
  8. Check for   globe icon on the thermostat.
  9. Log back into the app.

5. DHCP issue – blocked IP

Some routers may automatically block or conflict IPs assigned to the gateway.


Fix: Disconnect the gateway for 10+ minutes, then assign a static IP in router DHCP settings.


6. Restart router
  1. Turn off your router for at least 10 minutes.
  2. Power it back on and allow reconnection.
  3. The gateway should now connect (green LED).

7. Final step – factory reset and re-pairing
  1. Press and hold the SYNC button on the iTG500 for 5 seconds.
  2. On iT500 thermostat, launch pairing mode.
  3. When green LED appears, pairing is complete.

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