Electric wall/panel heater not working
A fixed electric heater (panel, wall, or in-slab) isn't heating — no warmth despite being switched on, pointing at the element, thermostat, controller, or supply.
Safety first
Isolate and prove dead before working. Fixed heaters can be on their own circuit/timer; in-slab heating is energised and not easily accessed.
Isolate, lock out / tag out, and prove dead before working unless a live test is specifically required, authorised, and carried out under proper supervision. Always follow local regulations, your site procedures, and the equipment manufacturer's documentation.
Apprentice mode
Full walk-through — the why, what readings mean, mistakes & safety.
Likely causes
Ranked from most to least likely.
- 1
Thermostat/controller set or faulty
Most likelyThe thermostat or controller isn't calling for heat (setting, timer, or fault).
- 2
Failed element
#2The heating element has gone open circuit.
- 3
No supply / tripped protection
#3A tripped breaker/safety switch or lost supply.
- 4
Timer/controlled-load not energising (in-slab)
Least likelySlab heating often runs on a timer/controlled load; it may not be energised.
Reports are saved on this device to reflect what you actually find.
Testing sequence
Work through one test at a time. Expected reading and what each result means.
On the tools? Job Mode shows one test at a time with thumb-sized buttons — your place and readings carry straight over.
Enter Job ModeConfirm the thermostat/controller is calling for heat and the timer/controlled-load is active.
Heat called; timer/controlled-load active when expected.
Heat called — check supply and the element.
Not calling / not in window — set correctly / chase the timer.
View all expected readings at once
Fault-finding flowchart
The same logic as a decision tree.
- 1start
Electric heater not working
→ step 2 - 2decision
Is the thermostat/controller calling and timer active?
Yes→ step 3No→ step 4 - 3decision
Is protection on and supply present?
Yes→ step 5No→ step 6 - 4result
Set correctly / chase the timer/controlled-load.
- 5decision
Is the element resistance/insulation good?
Yes→ step 7No→ step 8 - 6result
Restore supply (find why if tripped).
- 7result
Re-check controller/timer.
- 8result
Open element or low insulation — replace/rectify.
Common mistakes apprentices make
- Not realising slab/panel heating runs on a timer or controlled load.
- Resetting protection without finding why it tripped.
- Assuming the element when the controller isn't calling.
- Working live on a heater circuit.
When to stop & escalate
Fixed heater work is licensed electrical. In-slab element faults can be major (the element is in the slab) — get a licensed electrician to assess before assuming the worst.
If you're past your competence, authorisation, or the safe limits of the job — stop and hand it on. There's no fault worth getting hurt over.
Was this guide helpful?
Related faults
No hot water (electric storage system)
An electric storage hot water system has gone cold — no hot water at the taps. Usually the element, thermostat, supply, or (for off-peak) the tariff/timing.
Heater not heating at all
A heater (element, band, or bank) produces no heat — temperature won't rise, the process stays cold, despite the control calling for heat.
A circuit breaker keeps tripping (domestic)
One circuit breaker keeps tripping — instantly on reset or after a load runs — and you need to tell an overload from a short or a faulty appliance.