If your not sure whether to call a Plumber or an Electrician for your no hot water issue, its generally an electrical problem.
Hot Water Heating problems are normally related to one of the below issues:
Hot Water heater Thermostat
Hot Water Heater Element
Ripple Control Relay at Meter board
Shorting within cabling
A faulty hot water heater Switch
Faulty Fuse or associated Switchboard wiring
We can Help with all of the above issues. Every so often the problem for no Hot Water could be caused by a faulty Ajax Valve or a Temperature Tempering valve issue which will require a plumber to fix.