Electric Backup Heat Strip Calculator
Auxiliary heat strips are resistance heaters; their current is power divided by voltage.
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Formula
- I = (kW × 1000) ÷ V
- BTU/h = kW × 3,412
Example calculation
10 kW at 240 V → 41.7 A, 34,121 BTU/h.
Practical HVAC use
Check strip operation with an amp clamp and confirm staging.
Common mistakes
- Forgetting that 240 V-rated strips produce about 75% of rated output at 208 V.
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Educational tool. Results are estimates from the stated formulas; always confirm with manufacturer data and the code adopted in your jurisdiction. All calculators