Convert Hour-degree Fahrenheit per BTU to Second-degree Fahrenheit per BTU
Convert Hour-degree Fahrenheit per BTU (h·°F/BTU) to Second-degree Fahrenheit per BTU (s·°F/BTU) instantly and accurately.
Conversion Formula
s·°F/BTU = h·°F/BTU × 3600
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 Second-degree Fahrenheit per BTU
The second-degree Fahrenheit per BTU (s·°F/BTU) equals (5/9)/1055.05585262 K/W ≈ 5.265 × 10⁻⁴ K/W. Used in US aerospace and nuclear engineering where thermal transient analyses express power as BTU/s and temperature in °F, e.g. rocket engine heat rejection and reactor coolant loop calculations. 1 s·°F/BTU ≈ 5.265 × 10⁻⁴ K/W.
Quick Reference Table
| Hour-degree Fahrenheit per BTU (h·°F/BTU) | Second-degree Fahrenheit per BTU (s·°F/BTU) |
|---|---|
| 1 h·°F/BTU | 3600 s·°F/BTU |
| 2 h·°F/BTU | 7200 s·°F/BTU |
| 5 h·°F/BTU | 18000 s·°F/BTU |
| 10 h·°F/BTU | 36000 s·°F/BTU |
| 25 h·°F/BTU | 90000 s·°F/BTU |
| 50 h·°F/BTU | 180000 s·°F/BTU |
| 100 h·°F/BTU | 360000 s·°F/BTU |