ENVIRONMENTALLY FRIENDLY TECHNOLOGYSUPER ABSORPTION

° C, 1.5 ° C below setpoint.When the microprocessor issues a stop signal, the generator heat sourcewill shut off and the dilution cycle will start. The dilution cycle will last between 6 and 15 minutes depending on generator temperature. Thedilution cycle will consist of stopping of the refrigerant pump, absorbentpump(s), and the cooling water pump in turn. The unit is capable of re- starting during the dilution cycle. ° C, 2 ° C above setpoint.When the microprocessor receives a stop signal, the generator heatsource will shut off and the dilution cycle will begin. The dilution cycle will last approximately 5 minutes depending on generator temperature. Thedilution cycle consists of timed stopping of the No. 1 absorbent pump.The chiller/heaters is capable of restarting during the dilution cycle.

Sequence of cooling operation (DE) Sequence of heating operation (DE)

Figure 27 illustrates the typical operating sequence of a SANYO DE di-rect-fired absorption chiller / heaters. The NE steam-fired unit does not include the time delays associated with the burner blower, gas valve andignition functions.With a chilled water setpoint of 6.7 Figure 28 illustrates the typical operating sequence of a SANYO DE di-rect-fired absorption chiller/heaters in heating mode. With a hot water setpoint of 55 ° C, the start signal will be energized as theleaving heating water temperature drops to 54 ° C, 1.0 ° C below setpoint.The burner initially completes a 36-second pre-purge operation that in- cludes gas valve and supply air damper modulation to full open to insurecomplete purging of the combustion chamber. The No. 1 absorbent pumpflow rate is varied during all stages of operation to insure quicker start-up and optimum performance at part load. On chiller/heaters with two ab-sorbent pumps, the No. 2 pump remains off at all times during the heat-ing mode. As the heating load is satisfied with the chiller/heaters at minimum load,the unit will cycle off as the leaving heating water temperature rises to 57 ° C and with the chiller/heaters en-abled, the start signal will be energized as the leaving chilled water tem-perature rises to 7.7 ° C, 1.0 ° C above setpoint.The burner initially completes a 36-seconds pre-purge operation that in- cludes gas valve and supply air damper modulation to full open to insurecomplete purging of the combustion chamber.The No. 1 absorbent pump flow rate is changed during all stages of op- eration to insure quicker start-up and optimum performance at part load. As the cooling load is satisfied with the chiller/heaters at minimum load,the unit will cycle off as the leaving chilled water temperature drops to 5.5 Figure 27. Typical combustion time chart (cooling operation) Figure 28. Typical combustion time chart (heating operation)
BurnerBlower ONOFF BurnerBlower ONOFF Gas controlvalve OpenClose Gas controlvalve OpenClose Ignition ONOFF Ignition ONOFF Sol. valveIgnition gas ONOFF Sol. valveIgnition gas ONOFF Sol. valveMain gas ONOFF Sol. valveMain gas ONOFF No. 1 ABSOpump ONOFF No. 1 ABSOpump ONOFF No. 2 ABSOpump ONOFF Dilution cycleApprox. 5 min.Approx. 5 min. Pre-purge36 sec.Post-purge12 sec.ControlareaChiller stopStop signalStart signal4sec.2sec.2sec.8sec. Refrigerantpump ONOFF Dilution cycleApprox. 6 -- 15 min.Approx. 5 min. Pre-purge36 sec.Post-purge12 sec.ControlareaChiller stopStop signalStart signal4sec.2sec.2sec.8sec.

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