Retrofit

Retrofitting Strategy	Installation of auto-cleaning devices for condensers of water-cooled chillers
	Fouling inside the surface of condenser tubes will build up over time resulting in the increase of approach temperature of condenser. Auto-tube cleaning devices can reduce the accumulation of fouling and maintain a low approach temperature for the condenser and hence keeping the COP of chiller at a near “foul-free” condition. There are different types of tube cleaning devices. One type is using sponge balls either with or without circulation pumps and another type is using brushes that operate by reversing the flow within the condenser.
	Consideration
	The efficiency of the chillers can be maintained, and the cost and resources for manual cleaning of the condenser tubes can also be reduced. Tube cleaning balls need to be replaced from time to time. Tube cleaning systems using brushes require more space for the reverse flow mechanism. Installation of power meter, temperature sensors, and flowmeter or differential pressure sensors for monitoring the power, cooling energy and COP of chiller (Figure 1).
	Estimated Saving
	(TAPP,C_PRE – TAPP,C_POST)/19 * 1/COP_CH * QBLDG * OPHR,yr Where COP_CH = 0.605COP_CH_SM + 0.395COP_CH_WN COP_CH_SM = (COPa_SM + COPb_SM)/2; COP_CH_WN = (COPa_WN + COPb_WN)/2 QBLDG = 0.605[0.77(0.88NCH_SMQCH_SM + 0.12NCH_WNQCH_WN)] + 0.395[0.596(0.184NCH_SMQCH_SM + 0.816NCH_SMQCH_SM)] TAPP,C_POST = 2 for copper condenser tube, TAPP,C_POST = 5 for tritium condenser tube OPHR,yr = hr/dayday/wk52 Please click HERE to view the list of terminology.