Retrotec USACE - Manual (Page 235)

Appendix D D105
D.6.2 Pumps
D.6.2.1 Condensate Receiver Pumps Need Repair (Waste)
Figure D164. Well-maintained condensate
receiver with pump to send condensate back
to heating plant.
The condensed steam is collected at a condensate receiver and pumped back to the
boiler plant in good steam distribution systems (Figure D164). Failure to return
the condensate wastes heating energy and requires additional chemicals for water
treatment. At times the condensate is not returned due to leaks in the condensate
return piping, due to malfunctioning condensate return pumps, or by design. If a
steam user is too far removed from the condensate return piping system, the cost
to install condensate return components may be more than the value of the subject
condensate. In this case, the condensed steam would be dumped down a drain.
D.6.2.2 Constant-Speed Primary Chilled Water Pumps above 5 hp
(Ineffi ciency)
Installation of VFDs on the primary chilled water pumps will allow the speed of
the pumps to be varied in response to changes in the cooling loads and chilled
water system temperature differentials, rather than running always at full speed.
D.6.2.3 Constant-Speed Condenser Water Pumps (Ineffi ciency)
Figure D165. Constant-speed condenser water
pump.
Installation of VFDs on the condenser water pumps (Figure D165) will allow
the speed of the pumps to be varied in response to changes in the cooling
loads, rather than running always at full speed.