Condensate Pipe Lines - Friction Resistance Imperial Units

Friction or major resistance in condensate pipe lines. The table shows frictional resistance (major loss in inches H2O per 100 ft of pipe) for various pipe sizes and condensate mass flow rates. Avoid friction resistance above 10 inches Water gauge per 100 ft of pipe.

Pipe Size (inch)5 lb/h7 lb/h10 lb/h14 lb/h16 lb/h20 lb/h
1/2100240290350430460520
3/423056068082099010001200
1440107012001550180020002260
1 1/4950230027003300400043004800
1 1/21400350042005500610066007100
22800680081009900118001270014200
2 1/25700138001650020000239002570028900
39000215002580031000370003980044700
418600440005200063400755008100090900

Notes

  • Friction Resistance: Measured in inches H2O per 100 ft of pipe
  • Running Load Rule of Thumb: If startup conditions are unknown, double the running load to size condensate pipe lines
  • Maximum Recommended: Avoid friction resistance above 10 inches Water gauge - H2O - per 100 ft of pipe
  • Unit Conversion: 1 in = 25.4 mm

Example - Sizing Condensate Pipe

For a steam distribution system with a running load of 2000 lb/h - the startup condensate load is doubled to 4000 lb/h.

Using the 10 inch H2O column - a 1 1/2 inch pipe is acceptable.

Condensate Pipe Lines - Friction Resistance Imperial Units | MEPKit Engineering Tools | MEPKit