No Green LED - for 6-years - though renting flat now.

Hello,
I am going to rent my flat for a while and just getting things ship-shape. I have had issues with the PC2000, but thanks to this community, have fixed them along the way (mainly changing thermostats, filling header tank, etc.).
Around once every 4-months, the boiler 'overheats' and I have to do the old trick of turning off the boiler, pressing the reset button hidden under the black plastic screw; on the part leading from the copper wire coil. This doesn't bother me, but as I am renting flat, I am going to try and fix this by installing the overheat upgrade kit - so far so good.
I have lived with the PC2000 for 6-years and I remember the day I moved in the green LED was not on, but yet apart from the odd little fault along the way, this has never been an issue! The red LED on the front panel DOES light after an 'overheat' and the internal LED on the PCB does all its flash sequences as expected. Question is then - is it worth replacing a part to liven this green LED? What part would that be? Does this non-lit Green LED point to anything more suspicious (even though the boiler seems fine without it). Anyhow, I'm sure you all get my drift now?
Any answers, observations (maybe other have this too) all appreciated!
PC.

All the green LED tells you is that the control board has a live electricity feed present. As your Pulsacoil works, we can state with virtual certainty that the green LED lamp itself has failed. A common problem and few people bother fixing it as it doesn't matter.

Mike

The green LED is only a display to confirm the overheat stat has not tripped and power is present to the unit. The red light working is helpful and will do the job. The system will work as it always has without the green LED