Current drawn depends on voltage. Watts are voltage * current.
So, take your 25 watts, divide by supply voltage.
- at 120VAC supply - 0.208 amps
- at 208VAC supply - 0.120 amps
- at 240VAC supply - 0.104 amps
This is a slight approximation as the power factor may not be exactly 1 but close enough.
Watts convert to BTU/hour, not directly to BTU. One watt is approximately 3.412 BTU/hour so 25 watts is 85.3 BTU/hour.
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