Convert Hour-degree Fahrenheit per BTU to Millikelvin per watt

Convert Hour-degree Fahrenheit per BTU (h·°F/BTU) to Millikelvin per watt (mK/W) instantly and accurately.

Hour-degree Fahrenheit per BTU (h·°F/BTU)
Millikelvin per watt (mK/W)

Conversion Formula

mK/W = h·°F/BTU × 1895.634241

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 Millikelvin per watt

The millikelvin per watt (mK/W) equals exactly 10⁻³ K/W. It is used for ultra-low thermal resistances in high-conductivity materials such as diamond heat spreaders (≈ 0.3 mK/W per mm thickness for 1 cm² area), liquid metal TIMs, and cryogenic heat links. Measuring at this scale requires precision power dissipation and calorimetric temperature sensing. 1 mK/W = 10⁻³ K/W.

Quick Reference Table

Hour-degree Fahrenheit per BTU (h·°F/BTU)Millikelvin per watt (mK/W)
1 h·°F/BTU1895.63 mK/W
2 h·°F/BTU3791.27 mK/W
5 h·°F/BTU9478.17 mK/W
10 h·°F/BTU18956.3 mK/W
25 h·°F/BTU47390.9 mK/W
50 h·°F/BTU94781.7 mK/W
100 h·°F/BTU189563 mK/W

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