MCB Size for AC, Geyser & Heater
Which MCB for a 1, 1.5 or 2 ton AC, a geyser or a heater? Quick answer: 16 A for a 1 ton AC, 20 A for a 1.5 ton AC and 25 A for a 2 ton AC, all C curve, preferably double pole. Genuine Schneider MCBs with live prices below.
The chart gives typical values for 230 V single-phase appliances. Your appliance's installation manual and the cable size of the circuit always take priority. Prices checked 16 October 2026. Reviewed by Amit, Voltkart.
MCB size chart for AC, geyser and heater
| Appliance (230 V) | Typical running current | Recommended MCB | Double pole (live + neutral) | Single pole |
|---|---|---|---|---|
| Split / window AC, 1 ton | about 5–6 A | 16 A, C curve | 16 A DP ₹578 | 16 A SP ₹220 |
| Split / window AC, 1.5 ton | about 7–9 A | 20 A, C curve | 20 A DP ₹578 | 20 A SP ₹220 |
| Split AC, 2 ton | about 9–12 A | 25 A, C curve | 25 A DP ₹578 | 25 A SP ₹212 |
| AC 2.5–3 ton (single phase) | about 13–16 A | 32 A, C curve | 32 A DP ₹578 | 32 A SP ₹220 |
| Geyser / water heater, 2 kW | about 9 A | 16 A, C curve | 16 A DP ₹578 | 16 A SP ₹220 |
| Geyser / water heater, 3 kW | about 13 A | 20 A, C curve | 20 A DP ₹578 | 20 A SP ₹220 |
| Room heater, 2 kW | about 9 A | 16 A, C curve | 16 A DP ₹578 | 16 A SP ₹220 |
Running currents are typical; inverter ACs draw less at part load and more briefly at start-up. If in doubt, ask a licensed electrician.
Three-phase motors and machines
For 415 V three-phase motors, size protection from the motor current instead: see the motor full-load current chart, MPCB by motor kW and the motor starter chart.
All ratings, 1 to 4 pole: Schneider MCB price list. Comparing breaker types? Read MCB vs MCCB.
MCB for AC: frequently asked questions
Which MCB is best for a 1.5 ton AC?
A 20 A C-curve MCB is the usual choice for a 1.5 ton split AC on 230 V. Many inverter ACs run on a 16 A MCB, but 20 A gives margin for the compressor's starting current. Always check the rating given in your AC's installation manual, which overrides any general chart.
Should I use a single pole or double pole MCB for an AC?
A double pole (DP) MCB switches off both live and neutral, so the outdoor unit is fully isolated for servicing. It is the safer and more common choice for ACs and geysers. A single pole MCB only breaks the live wire.
Why a C-curve MCB for an AC?
Compressors draw a high current for a moment when they start. A C-curve MCB tolerates this short surge without tripping, while still protecting against overloads and short circuits. B-curve MCBs are meant for lighting and resistive loads and can trip on compressor starts.
Can I use a 32 A MCB for a 1.5 ton AC to stop it tripping?
No. An oversized MCB may not trip before the cable overheats. The MCB must suit both the appliance and the cable size of that circuit. If a correctly rated MCB keeps tripping, have the AC and wiring checked.
Do I also need an RCCB?
An MCB protects against overload and short circuit, not electric shock. An RCCB (residual current device) on the circuit or the distribution board adds shock and earth-leakage protection, which is especially useful for geysers and outdoor AC units.