Heater watts and amps
Electric heater amp check
Check how many amps a temporary electric heater will draw before you plug it in.
Safety boundary: this guide is for early planning only. It does not inspect hidden wiring, sign off an installation or replace a competent electrician.
The quick check
For a resistive electric heater, amps are approximately watts divided by volts. A 2,000 W heater on a 230 V supply is about 8.7 A; a 3,000 W heater is about 13.0 A before any other load is counted.
Why this matters
The problem is rarely one heater on its own. The risk starts when heaters, dehumidifiers, air movers, tills, chargers or workshop tools run together on a circuit nobody has checked.
What to do next
Use the load check to add all equipment together, then see whether the total stays below the warning point. If the heater count still looks workable, compare electric heater options instead of guessing from room size alone.
Equipment next step: if the load plan is realistic, compare electric heater options and keep the calculation trail with your site notes.