Carrier 50RHE006-060 specifications 50RHE Coaxial Water Pressure Drop

Table 9 — Typical Unit Operating Pressures and Temperatures

ENTERING	WATER				COOLING								HEATING
WATER	FLOW	Suction	Discharge	Super-		Sub-		Water Temp		Air Temp	Suction	Discharge	Super-	Sub-	Water Temp	Air
TEMP (C)		Pressure	Pressure	heat		cooling		Rise		Drop (C)	Pressure	Pressure	heat	cooling		Temp
	(l/s per kW)
(EWT)		(kPa)	(kPa)	(C)		(C)		(C)		DB	(kPa)	(kPa)	(C)	(C)	Drop (C) DB	Rise (C)
–1	0.027	225-254	269-314	14-22		7-11		12-13		12-14	102-117	499-556	7- 9	1-2	4-5	8-11
	0.041	222-251	239-284	14-22		6-10		7-	9	12-14	111-129	514-571	7- 9	1-2	3-4	9-12
	0.054	219-248	209-254	14-22		6-	9	3-	6	12-14	120-138	529-586	7- 9	1-2	2-3	9-12
10	0.027	225-254	374-463	7-11		6-10		11-13		11-14	150-179	538-628	6- 9	1-3	6-7	13-16
	0.041	222-251	359-425	7-11		5-	9	7-	8	11-14	158-185	553-643	6- 9	1-3	4-5	13-17
	0.054	219-248	344-413	7-11		4-	8	4-	7	11-14	164-194	568-658	6- 9	1-3	3-4	14-17
21	0.027	225-254	535-592	5-	9	4-	8	11-12		11-13	212-245	613-688	8-11	1-3	8-9	16-19
	0.041	222-251	502-556	5-	9	4-	7	7-	9	11-13	218-254	628-712	8-11	1-3	5-6	17-21
	0.054	219-248	472-523	5-	9	4-	7	4-	7	11-13	227-263	643-724	8-11	1-3	3-4	17-21
32	0.027	225-254	685-750	5-	9	4-	8	10-12		9-13	254-284	658-777	10-16	1-3	8-9	18-22
	0.041	222-251	652-721	5-	9	4-	7	6-	8	9-13	269-299	673-792	10-16	1-3	6-7	18-23
	0.054	219-248	622-688	5-	9	4-	7	3-	6	9-13	284-314	688-807	10-16	1-3	4-5	19-23
43	0.027	231-260	837-957	4-	8	6-14		9-11		8-11
	0.041	228-257	807-927	4-	8	6-13		5-	7	8-11
	0.054	225-254	777-897	4-	8	6-12		3-	6	8-11

LEGEND

DB — Dry Bulb

EAT — Entering Air Temperature

NOTES:

1.Based on nominal 54 L/s per kW airflow and 21° C EAT heating and 26.7/ 194° C EAT cooling.

2.Cooling air and water numbers can vary greatly with changes in humidity.

3.Subcooling is based upon the head pressure at compressor service port.

Table 10 — 50RHE Coaxial Water Pressure Drop

UNIT	L/S		PRESSURE DROP (kPa)
50RHE		0° C	10° C	20° C	30° C
006	0.047	6.0	5.4	5.1	4.8
	0.071	8.4	7.8	7.2	6.9
	0.095	14.1	13.2	12.0	11.7
009	0.071	8.1	7.5	6.9	6.6
	0.107	12.0	11.1	10.5	9.9
	0.139	23.9	22.4	20.9	20.0
012	0.095	19.1	17.9	16.7	16.1
	0.145	41.3	38.9	36.2	34.7
	0.189	66.1	61.9	57.7	55.0
015	0.114	16.7	15.5	14.7	14.1
	0.164	32.6	30.5	28.7	27.2
	0.221	55.9	52.3	48.7	46.3
019	0.142	12.9	12.0	11.1	10.8
	0.215	23.0	21.5	20.3	19.1
	0.284	45.4	42.5	39.8	37.7
024	0.189	13.8	12.6	11.7	11.4
	0.284	28.7	26.9	25.1	23.9
	0.379	47.8	44.9	41.9	39.8
030	0.237	9.9	9.0	8.4	8.1
	0.347	17.0	15.8	14.7	14.1
	0.473	26.9	25.4	23.6	22.4
036	0.284	7.8	7.2	6.9	6.6
	0.426	15.0	13.8	12.9	12.3
	0.568	23.9	22.4	20.9	20.0
042	0.331	9.9	9.3	8.7	8.4
	0.498	19.7	18.5	17.0	16.4
	0.663	31.1	29.3	27.5	26.0
048	0.379	14.1	13.2	12.3	11.7
	0.568	26.9	25.4	23.6	22.4
	0.757	44.0	41.0	38.3	36.5
060	0.473	33.5	31.4	29.3	27.8
	0.713	58.3	54.4	50.8	48.4
	0.947	88.5	82.8	77.1	73.3

Flushing — Once the piping is complete, units require final purging and loop charging. A flush cart pump of at least 1.5 hp (1.12 kW) is needed to achieve adequate flow velocity in the loop to purge air and dirt particles from the loop. Flush the loop in both directions with a high volume of water at a high velocity. Follow the steps below to properly flush the loop:

1.Verify power is off.

2.Fill loop with water from hose through flush cart before using flush cart pump to ensure an even fill. Do not allow the water level in the flush cart tank to drop below the pump inlet line to prevent air from filling the line.

3.Maintain a fluid level in the tank above the return tee to avoid air entering back into the fluid.

4.Shutting off the return valve that connects into the flush cart reservoir will allow 345 kPa surges to help purge air pockets. This maintains the pump at 345 kPa.

5.To purge, keep the pump at 345 kPa until maximum pumping pressure is reached.

6.Open the return valve to send a pressure surge through the loop to purge any air pockets in the piping system.

7.A noticeable drop in fluid level will be seen in the flush cart tank. This is the only indication of air in the loop.

NOTE: If air is purged from the system while using a 254 mm PVC flush tank, the level drop will only be 25 to 51 mm since liquids are incompressible. If the level drops more than this, flushing should continue since air is still being compressed in the loop. If level is less than 25 to 51 mm, reverse the flow.

8.Repeat this procedure until all air is purged.

9.Restore power.

Antifreeze may be added before, during or after the flushing process. However, depending on when it is added in the process, it can be wasted. Refer to the Antifreeze section for more detail.

Loop static pressure will fluctuate with the seasons. Pres- sures will be higher in the winter months than during the warm- er months. This fluctuation is normal and should be considered when charging the system initially. Run the unit in either heat- ing or cooling for several minutes to condition the loop to a homogenous temperature.

When complete, perform a final flush and pressurize the loop to a static pressure of 275 to 345 kPa for winter months or 105 to 135 kPa for summer months.

After pressurization, be sure to remove the plug from the end of the loop pump motor(s) to allow trapped air to be discharged and to ensure the motor housing has been flooded. Be sure the loop flow center provides adequate flow through the unit by checking pressure drop across the heat exchanger. Compare the results to the data in Table 10.

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