c.Inspect all field- and factory-wiring connections. Be sure that connections are completed and tight.
d.Ensure wires do not touch refrigerant tubing or sharp sheet metal edges.
e.Inspect coil fins. If damaged during shipping and handling, carefully straighten fins with a fin comb.
4.Verify the following conditions:
a.Make sure that outdoor-fan blade is correctly positioned in fan orifice. Top edge of blade should be 3.125 in.(79
mm) down from outdoor coil outlet grille (size
024-048, See Fig. 19) or hub should be 0.708-in. (18
mm)away from motor end bell (size 060, See Fig. 19). See Outdoor Fan Adjustment section.
b.Make sure that air filter is in place.
c.Make sure that condensate drain pan and trap are filled with water to ensure proper drainage.
d.Make sure that all tools and miscellaneous loose parts have been removed.
START-UP
Step 1 — Check for Refrigerant Leaks
Proceed as follows to locate and repair a refrigerant leak and to charge the unit:
1.Locate leak and make sure that refrigerant system pressure has been relieved and reclaimed from both high- and low-pressure ports.
2.Repair leak following accepted practices.
NOTE: Install a filter drier whenever the system has been opened for repair.
Step 2 — Start-Up Cooling and Make Adjust- ments
Complete the required procedures given in the Pre-Start-Up section before starting the unit. Do not jumper any safety devices when operating the unit. Do not operate the unit in cooling mode when the outdoor temperature is below 40°F (4.4°C) (unless accessory low-ambient kit is installed). Do not rapid cycle the compressor. Allow 5 min. between “on” cycles to prevent compressor damage.
CHECKING COOLING AND HEATING CONTROL OPERATION
Start and check the unit for proper cooling control operation as follows:
1.Place room thermostat SYSTEM switch in OFF position. Observe that blower motor starts when FAN switch is placed in ON position and shuts down within 60 sec. (for 024-042) or 90 seconds (for 048 and 060) when FAN switch is placed in AUTO position.
2.Place SYSTEM switch in COOL position and FAN switch in AUTO position. Set control below room temperature. Observe that compressor, outdoor fan, and indoor blower motors start and that reversing valve shifts. Observe that cooling cycle shuts down when control setting is satisfied. Reversing valve (RV) remains energized.
3.Place system switch in HEAT position. Observe that compressor, indoor fan and outdoor fan energize (Reversing Valve is deenergized in heat pump heating mode). Set control above room temperature. Observe that heating cycle shuts down when control setting is satisfied.
4.When using an automatic changeover room thermostat, place both SYSTEM and FAN switches in AUTO positions. Observe that unit operates in Cooling mode when temperature control is set to call for Cooling (below room temperature), and unit operates in Heating mode when temperature control is set to call for Heating (above room temperature).
Step 3 — Refrigerant Charge
Refrigerant Charge — Amount of refrigerant charge is listed on unit nameplate and in Table 1. Refer to Bryant Refrigerant Service Techniques Manual, Refrigerants section. Unit panels must be in place when unit is operating during charging procedure. Unit must operate a minimum of 15 minutes before checking charge.
NO CHARGE
Refer to Bryant Refrigerant Service Techniques. Use standard evacuating techniques. After evacuating system, weigh in the specified amount of refrigerant (refer to Table 1).
LOW CHARGE COOLING
024-042 units:
1.Measure suction line pressure by attaching a gauge to the service port.
2.Measure the suction line temperature by attaching a temperature sensing device to it.
3.Insulate the temperature sensing device so that the outdoor ambient doesn’t affect the reading.
4.Locate the measured suction line pressure in the top row of Table 5 and the measured outdoor ambient temperature in the left column of the table. Based on the two values, determine the required suction line temperature.
5.If the measured suction line temperature is greater than the tabulated temperature, add charge in the system.
048 and 060 units:
1.Measure discharge line pressure by attaching a gauge to the service port.
2.Measure the liquid line temperature by attaching a temperature sensing device to it.
3.Insulate the temperature sensing device so that the outdoor ambient doesn’t affect the reading.
4.Refer to the required subcooling in Tables 3 to find the required subcooling based on the model size and the outdoor ambient temperature.
5.Interpolate if the outdoor temperature lies in between the table values. Extrapolate if the temperature lies beyond the table range.
6.Find the pressure value corresponding to the measured pressure on the compressor discharge line.
7.Read across from the pressure reading to obtain the Liquid line temperature for a required subcooling.
8.Add charge if the measured temperature is higher than the liquid line temperature value in the table.
9.Add charge using the service connection on the suction line of the compressor.
HEATING MODE CHARGE
Do not attempt to adjust charge by cooling methods while in heat pump heating mode. Recover refrigerant and weigh in according to unit data plate refrigerant data.
