Convert Hour-degree Fahrenheit per BTU to Degree Celsius per milliwatt
Convert Hour-degree Fahrenheit per BTU (h·°F/BTU) to Degree Celsius per milliwatt (°C/mW) instantly and accurately.
Conversion Formula
°C/mW = h·°F/BTU × 0.001895634241
About Hour-degree Fahrenheit per BTU
The h·°F/BTU equals (5/9 × 3600)/1055.05585262 K/W ≈ 1.8956 K/W. It is the traditional US unit for thermal resistance in HVAC, building science, and insulation engineering. A pipe fitting with R = 1 h·°F/BTU passes 1 BTU/h per °F driving difference. Appears in ASHRAE handbooks, ASTM C177, and older US plumbing codes. 1 h·°F/BTU ≈ 1.8956 K/W.
About Degree Celsius per milliwatt
The degree Celsius per milliwatt (°C/mW) equals exactly 1000 K/W since 1 mW = 10⁻³ W and 1 °C = 1 K. Widely used in low-power semiconductor datasheets for characterising junction-to-ambient resistance: small-signal transistors, LEDs, photodiodes, and SMD resistors typically show RθJA of 50-500 °C/mW. A device at 200 °C/mW dissipating 5 mW rises 1 °C. 1 °C/mW = 1000 K/W = 1 kK/W.
Quick Reference Table
| Hour-degree Fahrenheit per BTU (h·°F/BTU) | Degree Celsius per milliwatt (°C/mW) |
|---|---|
| 1 h·°F/BTU | 0.00189563 °C/mW |
| 2 h·°F/BTU | 0.00379127 °C/mW |
| 5 h·°F/BTU | 0.00947817 °C/mW |
| 10 h·°F/BTU | 0.0189563 °C/mW |
| 25 h·°F/BTU | 0.0473909 °C/mW |
| 50 h·°F/BTU | 0.0947817 °C/mW |
| 100 h·°F/BTU | 0.189563 °C/mW |