Size Vacuum Condensate Return

Pump Flow Rate

Pumps sized at two times (2x) the normal condensing or evaporation rate based on a quicker return rate of the condensate than non-vacuum condensate units.

Pump Flow Rate at 2x condensing rate 1
0 gallons ⁄ min (GPM)

Minimum Receiver Size

Minimum Receiver Size is determined from Pump Flow Rate. Make sure the inlet height is lower or equal to existing height on gravity return systems—water does not run uphill! 2

Minimum Receiver Size
0 gallons

Vacuum Air Producer Sizing

Vacuum Air Producer Size is determined from Pump Flow Rate. If system is new, load is calculated based on 0.5 cubic feet of air removed per minute (CFM) for each 1000 square feet EDR. If an older system, load is based on 0.7 CFM per 1000 sq. ft. EDR to compensate for leaks. 3

New System at 0.5 CFM per 1,000 square feet EDR
0 CFM
Old System at 0.7 CFM per 1,000 square feet EDR
0 CFM

Pump Discharge Pressure

WARNING: The discharge pressure is used for sizing a complete unit. If sizing a replacement water pump for a condensate vacuum, the discharge pressure (psig) must be increased by the amount of vacuum that the pump is running under. The incremental calculation is based on the following relationship: 1" Hg equals 1 foot of head. Therefore, if the pump is running under 10" Hg, the discharge pressure must be increased by 4.3 psig (eg. 10" Hg = 10 feet of head = 4.3 psig).

feet (of head)
psig

If you enter "0" (zero), the calculator assumes the proper diameter for discharge pipe (velocity = 10 feet ⁄ second or less) and includes a safety margin of 10 PSIG.

If you do not know this value, use the Pipe Friction Calculator to determine resistence of piping (expressed in feet of head).

feet
Pump Discharge Pressure 5
0 psig
  • Pumps sized at two times the normal condensing or evaporation rate based on a quicker return rate of the condensate than non-vacuum condensate units.
  • Make sure the inlet height is lower or equal to existing height on gravity return systems—water does not run uphill!
  • If new system, load is calculated based on 0.5 cubic feet of air removed per minute (CFM) for each 1000 square feet EDR. If older system, based on 0.7 CFM per 1000 sq. ft. EDR to compensate for leaks in the system.
  • If value of "0" entered, calculator assumes proper diameter for discharge pipe (velocity of 10 feet per second or less) and includes a safety margin of 10 psig. If value not known, use Pipe Friction Calculator to determine resistence of piping in feet of head.
  • WARNING: The discharge pressure is used for sizing a complete unit. If sizing a replacement water pump for a condensate vacuum, the discharge pressure (psig) must be increased by the amount of vacuum that the pump is running under. The incremental calculation is based on following relationship: 1" Hg equals 1 foot of head. Therefore, if pump is running under 10" Hg, the discharge pressure must be increased by 4.3 psig (eg. 10" Hg = 10 feet of head = 4.3 psig)
  • Pump flow rate is < 0.5 gallons/min (gpm). Contacting your Shipco® representative is advised.
  • Pump flow rate is > 500 gallons/min (gpm). Contacting your Shipco® representative is advised.