Sizing Vacuum Condensate Units

Step 1 : Pump Flow Rate Sizing
Enter Load expressed as any of the following units in the drop-down list.	At 2 times evaporation or condensing rate
Boiler HP Sq. Feet EDR Lbs./Hour BTUs/Hour MBH Kilowatt (kW)	pump GPM
	#1
Result is LESS than 0.5 pump GPM. We advise you contact your Shipco representative. Result is GREATER than 500 pump GPM. We advise you contact your Shipco representative.
Step 2 : Minimum Receiver Size
Calculated automatically from results in Step 1.	gallons
	#2
Step 3 : Vacuum Air Producer Sizing
Calculated automatically from results in Step 1.	New System (0.5 CFM per 1000 sq. ft. EDR)	Old System (0.7 CFM per 1000 sq. ft. EDR)
	CFM	CFM
	#3	#3
Step 4 : Pump Discharge Pressure Sizing
1. Enter Vertical Lift. feet of head 2. Enter Back Pressure. psig 3. Enter loss of head due to discharge pipe friction. feet #4	pump discharge psig #5
Use Pipe Friction Calculator
Press "Reset All" to CLEAR ALL calculations and enter new values.

Notes

1. 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.
2. Make sure the inlet height is lower or equal to existing height on gravity return systems—water does not run uphill!
3. 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.
4. 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.
5. 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 ft. of head. Therefore, if pump is running under 10" Hg, the discharge pressure must be increased by 4.3 psig (eg. 10" Hg = 10 ft. of head = 4.3 psig)

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