7
REFRIGERANT CHARGING
The 07KHP units are packed with refrigerant holding charge only.
Proper refrigerant charge is determine using Superheat method.
IMPORTANT
For accurate system performance, charge by superheat method as
shown in table 6 and 7.
To check and adjust charge, follow the following procedures:
1.
Operate unit for a minimum of 30 minutes before checking
charge.
2.
Measure suction pressure by attaching a gauge to suction
line service port.
3.
Measure suction line temperature by attaching a service
thermometer to unit suction line near suction valve. Insulate
thermometer for accurate readings.
4.
Measure entering water temperature with a second
thermometer.
5.
Measure indoor coil air inlet wet-bulb temperature with a sling
psychrometer.
6.
Refer to table 4. Find entering water temperature and wet-
bulb temperature entering indoor coil. At this intersection,
note the superheat.
7.
Refer to table 5. Find superheat and temperature and suction
pressure, note suction line temperature.
8.
If unit has higher suction line temperature than charted
temperature add refrigerant until charted temperature is
reached.
9.
If unit has lower suction line temperature than charted
temperature, bleed refrigerant until charted temperature is
reached.
10. If entering water temperature or pressure at suction line
changes, charge to new suction line temperature indicated on
chart.
11. This procedure is valid independent of indoor air quantity.
MAINTENANCE
Remove unit’s access panels for internal servicing and maintenance
.
LUBRICANT
Compressor contains factory oil charge. Replace oil when lost. See
table 3 for oil recharge and refer to Carrier Manual Chapter 1, page 1-21
for oil recharging procedure.
CLEANING HEAT EXCHANGER
Use a tank with 5% phosphoric acid. Pump the cleaning liquid through
the plate heat exchanger at 1.5 times normal flow rate for optimum
cleaning, preferably in back flush mode. Then, rinse with large amount
of fresh water to get rid of all the acid before starting up the system
again. Clean at regular interval.
TABLE 4 AIR AND WATER LIMITS
LIMITS
STANDARD TEMPERATURE
AIR
(C)
Min. Ambient Air
21
Rated Ambient Air
27
Max. Ambient Air
43
Min. Entering Air at Evap
21
Rated Entering Air, DB/WB
27/19
Max Entering Air, DB/WB
32/23
WATER
(C)
Min. Entering Water
15
Normal Entering Water
29.5
Max Entering Water *
35
TABLE 5 WATER FLOW LIMITATIONS
UNIT MODEL NO. - 07KHP
MAX / MIN L/S (GPM)
013
0.25 / 0.1
(4 / 1.5)
018
0.38 / 0.14
(6 / 2.3)
024
0.5 / 0.19
(8 / 3)
040
0.76 / 0.28
(12 / 4.5)
060
1.26 / 0.47
(20 / 7.5)
090
1.89 / 0.72
(30 / 11.5)
CAUTION
TO PREVENT PERSONAL INJURY, WEAR SAFETY GLASSES
AND GLOVES WHEN HANDLING REFRIGERANT. DO NOT
OVERCHARGED SYSTEM. THIS CAN CAUSE COMPRESSOR
FLOODING.
CAUTION
BEFORE PERFORMING RECOMMENDED MAINTENANCE, BE
SURE UNIT MAIN POWER SWITCH IS TURNED OFF. FAILURE
TO DO SO MAY RESULT IN ELECTRIC SHOCK OR INJURY.
*
At maximum water flow conditions only as shown on Table 5
below
NOTE: Water flow must be sufficient to obtain a maximum 10F
temperature rise across the water-to-refrigerant heat exchanger when
operating in the cooling mode. Water flow rates greater than 4.0 GPM
per nominal ton or water velocities of 10 ft/sec or more may cause
erosion damage to the water-to-refrigerant heat exchanger.
Summary of Contents for 07KHP
Page 5: ...5 FIG 6 CEILING MOUNTED INSTALLATION FIG 7 FLOOR MOUNTED INSTALLATION ...
Page 8: ......
Page 10: ...10 FIG 8 WIRING DIAGRAM 07KHP012 FIG 9 WIRING DIAGRAM 07KHP018 024 ...
Page 11: ...11 FIG 10 WIRING DIAGRAM 07KHP040 050 FIG 11 WIRING DIAGRAM 07KHP060 ...
Page 12: ...12 FIG 12 WIRING DIAGRAM 07KHP090 FIG 13 RECOMMENDED SERVICE CLEARANCES ...
