Sterling 882.93092.01 manual Water column = Pascal GP Series Portable Chillers Appendix

Notes:

Customer use of ductwork requires the high pressure fan option.

Allow 30 in. (77 cm) minimum clearance around the chiller footprint to facilitate free passage of cooling air and service accessibility.

Figure 20 shows the pressure loss per foot of ductwork. Calculate the total equivalent length before using the data below.

Support ductwork from the building structure, not off of the chiller.

Back draft damper to outside must be closed at all times when fan/blower is not operating. Size the damper so that the pressure drop across is no greater than 0.2 in WG (50 Pascal) at the rated output.

Chillers are designed to operate at a condensing entering air temperature of 60ºF (16ºC) minimum without optional Variable Frequency Drive.

Figure 20 - Loss of Pressure through round duct - inches of water column per equivalent foot

	60 hz Condenser Fan Flow Rate (cfm / cmm)				50 hz Condenser Fan Flow Rate (cfm / cmm)
Nominal	GPAC-20	GPAC-30	GPAC-40	GPAC-50	GPAC-20	GPAC-30	GPAC-40	GPAC-50
Duct
Diameter		6343 /	8458 /	12687 /	3525 /	5286 /	7048 /	10573 /
(in / cm)	4230 / 120	180	240	360	100	150	200	300
18 / 45	0.003	0.007	0.013	0.03	0.002	0.005	0.009	0.020
20 / 50	0.002	0.005	0.008	0.02	0.001	0.003	0.005	0.012
22 / 55	0.001	0.003	0.005	0.01		0.002	0.003	0.007
24 / 60		0.002	0.003	0.007		0.001	0.002	0.005
26 / 65		0.001	0.002	0.004			0.001	0.003
28 / 70			0.001	0.003				0.002
30 / 75				0.002				0.002
32 / 80				0.002				0.001
36 / 90				0.001
Note: 1 inch	of water column = 250		Pascal

GP Series Portable Chillers Chapter 7: Appendix 78 of 90