ID COIL WITH EXPANSION VALVE
At stabilized cooling conditions and with an outdoor tem- perature of 60°F or higher, the subcooling at the outdoor unit liquid line service valve should be as specified in the specification sheet. Add or remove charge as required.
ID COIL WITH ORIFICE
For a proper superheat reading, measure the refrigerant pressure and temperature at the outdoor unit vapor line service valve. The superheat should be within 3°F of that shown on the Desired Superheat vs Outdoor Temperature chart (see page 9). If the superheat is higher, add charge. If the superheat is lower, remove charge.
EXAMPLE: The low side pressure is 84 psi. The low side temperature is 80°F. The outdoor temperature is 95°F. The indoor temperature is 85°F. By referring to a pressure temperature chart, you will see that 84 psi equals a saturated temperature of 50°F. The superheat is 80 - 50
= 30°F. The chart shows a superheat of 20°F is ideal for |
DEFROST TIME ADJUSTMENT PIN
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| FAN |
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| CC |
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30 |
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| |
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60 |
| DEFROST | RV |
90 | TEST | ||
| BOARD |
| |
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| DFS | |
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| WC RO Y |
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Figure 5
these conditions. Since our superheat is 30 - 20 = 10°F |
higher than ideal, charge must be added. |
If the system is performing properly, reinstall the service port caps and the valve bonnets. With the valve opened, the valve bonnet is the primary seal against refrigerant leaks. See the table below for the torque required for an effective seal on the valve bonnet (1/6 turn past finger tight).
Tubing Size | Torque |
3/8 | 10 |
1/2, 5/8, 3/4 | 14 |
7/8, 1 1/8 | 16 |
After closing the valve bonnet, perform a final refrigerant leak test on the valves and sweat connections. Return the room thermostat to the desired settings.
Troubleshooting
(QUALIFIED SERVICER ONLY)
When troubleshooting, the first step should always be to check for clean coils, clean filter(s), and proper airflow. Indoor airflow should be 350 to 450 CFM per ton of cooling, based on the size of the outdoor unit.
If further information is needed, see the Remote Heat Pump Service Manual or contact your Amana distributor.
Defrost System
Your unit is equipped with a time/temperature defrost board. Defrosting of the outdoor coil is determined by both coil temperature and compressor run time. See the “Specification Sheet” for factory settings. Adjustment can be changed as required. There are 30, 60, and 90 minute settings available. Adjust only if geographical conditions, outdoor humidity, or other adverse conditions make it necessary.
NOTE: If the time select pin remains in test position for 5 minutes, the control will ignore test mode and assume a normal 90 minute defrost cycle. To over ride this time out, remove the select pin briefly and replace back on test.
WARNING
To avoid electrical shock or death, disconnect the power before changing the defrost time cycle.
If adjustment of the run time appears advisable:
1.Disconnect power to outdoor unit.
2.Move the defrost time adjustment pin from 90 minutes to 60 minutes or 30 minutes as required (refer to Figure 5).
3.Reconnect the electrical power.
The maximum defrost time is 14 minutes. Most defrost cycles are shorter.
SERVICING: When servicing, it may be necessary to rapidly advance the system through a defrost cycle. To do this:
Place the defrost time adjustment pin on Test. When the unit starts the defrost cycle, quickly remove the time select pin to allow normal defrosting and defrost termination to proceed. The select pin may be reconnected to test or repeat the defrost cycle, or the pin may be placed in the desired time setting. (Jumping both test pins with a small insulated screw driver will also work.)
WARNING
To avoid electrical shock or death, disconnect the electrical power before servicing.
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