My Lennox Montebello fireplace will not start. There is no pilot, it appears to use electronic start. I can switch it on and there is a clicking sound like it's trying to start but no flame appears. I tried removing the grate and burner, cleaning everything and checking the gas line for obstruction, but nothing worked. In my opinion, no gas is coming into the burner. I removed the right side panel and noticed that there is an electronic device called Synetek IS1141U which has a constant flashing LED (picture uploaded). On the device is says: "Constant Flash: Internal Fault or False Flame". Is it likely that I can replace this device and that would fix the problem, or is it more likely that the gas valve is faulty?

Thanks,
Barry