2nd green light off. Heat sensor fault?

Hi
I noticed the water was not as hot as normal and the 2nd green light was off. The manual overheat had not popped out so i checked the thermostat overheat button. One of them had tripped so i reset that. The water has got hotter again but the light is still off (could this be a faulty light?). The PCB is flashing constantly indicating a heat sensor fault.

Do i need to change both of them and do i have to drain the tank to do this?
Everything seems to working as normal?

Thanks in advance
Dave

Hi Dave,

If there is a reset button on the heater thermostat then your second green light has probably been OFF since the heater thermostats were upgraded! The fact that it all gets hot again with the light OFF tells us the green light bulb has either failed or been taken out of circuit.

The PCB flashing continuously is a separate issue. It should be giving two quick flashes, once a second. The continuous flashing is telling us the DHW sensor has failed and needs changing. No need to drain the tank. But if it works to your satisfaction then why 'fix' it?

Cheers, Mike

Thanks Mike

Thats what i thought. If it ain't broke don't fix it.
Don't want to create more problems by trying to replace it, though if it continues to happen i may do it in future.

By the way, great site and excellent information on the Pulsacoil. I would have been lost without it.

Many Thanks
Dave

If it is working, don't worry so much about the neon, it could have blown.