Renovation · CEC Section 62 (Fixed Electric Space Heating)

Electric Heater Load Calculator

Size circuit breakers and conductors for baseboard heaters, fan-forced wall heaters, and garage unit heaters using the mandatory CEC 80% continuous heating rule.

1. Electric Heating Loads

Supply Voltage

Total Connected Heater Wattage

2. Heating Circuit Results

CEC Section 62 80% Rule

NOMINAL HEATER CURRENT

12.5 Amps

MINIMUM BREAKER RATING (125%)

20A 2-Pole Breaker

MINIMUM COPPER NMD90 WIRE

12/2 NMD90 (Red & Black)

CEC Section 62 Rule: Electric space heating is a continuous load. Maximum allowable wattage on a 20A 240V circuit is 3,840 Watts (80% of 4,800W).

CEC Section 62 Heating Rules

Baseboard heater circuits must not exceed 80% of the branch circuit rating (e.g. 2,880W max on 15A 240V, 3,840W max on 20A 240V).
Baseboard heaters must not be installed directly below electrical wall receptacles per CEC Rule 62-118.
Line-voltage thermostats break both ungrounded hot conductors or have a marked OFF position for safety isolation.