Reznor ZQYRA Unit Installation Manual - Manual (Page 66)

Form I-ZQYRA P/N 260414R5, Page 66
Refrigerant Charge and Check - The unit is factory charged and should require no further adjustment at startup.
Follow these steps to check the refrigerant charge.
NOTE: System charging is not recommended below 70°F (21°C).
1. Attach gauge manifolds and operate the unit in test mode.
2. Set the unit to its nominal airflow (Paragraph 9.3.1).
ZQYRA-8: 800 cfm supply and 1600 cfm exhaust
ZQYRA-12: 1200 cfm supply and 2400 cfm exhaust
3. Turn the wheel off and run the unit in cooling mode until
system stabilizes (approximately 5 minutes).
4. Compare the normal operating pressures in the tables
(right) to the pressures obtained from the gauges.
Minor variations in these pressures may be expected due
to the differences in installations. Significant differences
could mean that the system is not properly charged or
that a problem exists with some component in the system.
Correct any system problems before proceeding.
5. If discharge pressure is high, remove refrigerant from the
system.
If discharge pressure is low, add refrigerant to the system.
Add or remove charge in small increments. Continue
check until pressures are determined to be correct.
WARNING
Do not release refrigerant to the atmosphere.
When adding or removing refrigerant, the
qualified technician must comply with all
national, state/province, and local laws.
ZQYRA-8
Outside Air
Temperature
(ºF)
Suction
Pressure
±5 psig
Discharge
Pressure
±10 psig
Return Air Temperature is 75ºF
70 86 344
75 93 363
80 100 383
85 108 404
90 117 425
95 126 447
100 136 469
105 147 493
Return Air Temperature is 80ºF
70 87 357
75 94 376
80 101 396
85 109 417
90 118 439
95 127 461
100 137 484
105 148 507
Return Air Temperature is 85ºF
70 88 370
75 95 390
80 102 410
85 110 431
90 118 453
95 128 475
100 138 498
105 149 522
ZQYRA-12
Outside Air
Temperature
(ºF)
Suction
Pressure
±5 psig
Discharge
Pressure
±10 psig
Return Air Temperature is 75ºF
70 104 307
75 111 323
80 119 339
85 128 357
90 138 375
95 148 394
100 159 413
105 171 433
Return Air Temperature is 80ºF
70 105 317
75 112 334
80 121 351
85 129 369
90 139 387
95 149 406
100 160 426
105 173 446
Return Air Temperature is 85ºF
70 106 329
75 113 345
80 121 363
85 130 381
90 140 399
95 151 418
100 162 438
105 174 459
Coils and Tubing - Inspect the coils for debris, dirt, grease, lint, mold, or any element
which would obstruct heat transfer or airflow. Inspect coils and tubing for physical dam-
age. Inspect feeders, piping connections, coil headers, and return bends for signs of
fatigue, rubbing, and physical damage.
To clean the coils, use the proper tools and follow the instructions carefully to avoid
damaging the coil. Use of a non-acid based coil cleaner is recommended. Due to pos-
sible damage to the coil, high pressure spray is not recommended.
Cleaning Instructions:
1. Verify that the electrical power has been turned off and disconnect switch locked.
2. Open the coil cabinet door.
3. Use a soft brush to remove any dirt and debris from both sides of the coil.
4. Spray with cold or warm (not hot) water and a cleaning solution (non-acid based
coil cleaner is recommended). Due to possible damage to the coil, high pressure
spray is not recommended. First spray the leaving airflow side, then the inlet
airflow side. As much as possible, spray the solution perpendicular to the face of
the coil. Follow the instructions on the cleaning solution. When cleaning process is
complete, rinse both sides with cool, clean water.
Condensate Pan and Drain - The combination of airborne particles and moisture
can result in algae formation in the drain pan and trap. The drain pan and trap must
be cleaned regularly to avoid blockage that can slow or stop water flow, resulting in
backup into the cabinet. Clean the drain pan, trap, and piping. After cleaning, re-install
all parts and fill the trap with water to ensure proper operation.
10.0 Maintenance
and Service
(cont’d)
10.2 Maintenance Procedures (cont’d)
10.2.5 Heat Pump Maintenance (cont’d)