Any way to remove a device that no longer respnondes to the ISY, broken...out of range what ever the case.... can this device be deleted or removed manually?

Right click the primary device node and select Delete.

 

The better approach assuming the device is being replaced with a functional one is to add the new device under a temporary Name. The Right click the old defective device node, select Replace xxxx With ..... and select the new device Name. The ISY will replace all references to the defective device Insteon address with the new device Insteon address, leaving the original device Name in Programs and Scenes unaffected.

 

The old Insteon address is not sent commands so the old device can even be removed and physically replaced with the new device before invoking the Replace xxxx With .... function.