another heater problem

[nicnet]

Good news is that the problem is fixed:

>>> Could be worn out solder joints on the heater control panel.


It seems that this was exactly the problem. I resoldered all the joints on the unit (I suppose there's 30-50 of them), took about 10 mins.

Now the heating is steady and hot.
Also removing and putting back that unit has made the lights on the heater controls work - perhaps the leds were loose.