Megaflo water heater not working

Heatrae Megaflo type with 2 heater elements and 2 separate programmers. After a thunderstorm (coincidence?) last week the megaflo water heater stopped working. The circuit breaker did not trip out but the light has gone out on the 20A water heater switch. However the lights are on on both of the programmers. I tried putting the programmers to boost but not working. Could you please suggest what I should check first? I am a careful DIY’er and am particularly cautious around electricity! Many…

Megaflo water heater not working