Carrier 30HL050, 30HW018-040, 060 Ð Minimum Cooler and Condenser Flow Rates Minimum Loop Volume

The cooler ¯uid inlet and outlet connections are grooved- end. On 30HW units, the ¯uid enters at the top connection and leaves at the bottom connection. Procedures for making the grooved-end connections are the same as for the 30HWB condensers. See 30HWB Condenser section on page 16 for more details.

Run the pump for 10 minutes, then clean the strainer be- fore starting the unit.

A cooler ¯ow switch must be ®eld-installed on all units. This should be a differential pressure switch that is installed between the cooler ¯uid inlet and outlet. The switch should be set to open when the cooler ¯uid ¯ow drops below the values shown in Table 3. Use the cooler water pressure drop curves (Fig. 16) to determine correct setting for each unit size. Use Carrier accessory ¯ow switch, part number 30HW900003. See Table 3 for Minimum Flow rates and loop volumes.

See Step 6 Ð Make Electrical Connections section on page 19 for ¯ow switch wiring details.

30HK, HL Units Ð The thermistor used for sensing ¯uid temperature is factory-installed in the cooler leaving ¯uid line.

30HW Units Ð The thermistor used for sensing the ¯uid temperature is inside the cooler leaving-water cavity.

COOLER PRESSURE DROP Ð 30HW UNITS

Table 3 Ð Minimum Cooler and Condenser Flow

Rates Minimum Loop Volume

UNIT SIZE	COOLER		CONDENSER*		MINIMUM COOLER
					LOOP VOLUME²
	Gal./Min	L/s	Gal./Min	L/s	Gal.	L
30HK040	56.0	3.5	67	4.23	120	454.2
30HK,HL050	68.0	4.3	76	4.79	148	560.2
30HK,HL060	68.0	4.3	83	5.24	174	658.6
30HW018	22.5	1.4	22.5	1.4	44	167
30HW025	30.0	1.9	30.0	1.9	59	223
30HW028	37.5	2.4	37.5	2.4	76	288
30HW035	45.0	2.8	45.0	2.8	85	322
30HW040	57.0	3.6	57.0	3.6	113	428

LEGEND

ARI Ð Air Conditioning and Refrigeration Institute

NÐ Liters per kW

V Ð Gallons per ton

*30HK, HWB, HWC and HWS only. ²Minimum system ¯uid volumes.

NOTES:

Gallons = V x ARI capacity in tons.

Liters = N x ARI capacity in kW.

APPLICATION	V	N
Normal Air Conditioning	3	3.25
Process Type Cooling	6 to 10	6.5 to 10.8
Low Ambient Operation	6 to 10	6.5 to 10.8

COOLER PRESSURE DROP Ð 30HK, HL UNITS

NOTE: Ft of water = 2.31 x change in psig.

Fig. 16 Ð Cooler and Condenser Water Pressure Drop

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