Rheem ASL-JEC Series, Руководство по установке

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A thermostat and a 24 volt, 40 VA minimum transformer are required for the control
circuit of the condensing unit. The furnace or the air handler transformer may be
used if sufficient. See the wiring diagram for reference. Use Table 6 to size the 24
volt control wiring.
14.0 START-UP AND PERFORMANCE
Even though the unit is factory charged with Refrigerant-410A, the charge must be
checked to the charge table attached to the service panel and adjusted, if required.
Allow a minimum of 5 minutes of run time before analyzing charge.
At initial start-up or after extended shutdown periods, make sure the heater is ener-
gized for at least 12 hours before the compressor is started. (Disconnect switch on
and wall thermostat off.) Connect the communicating system per Figure 5. Once all
devices are connected, power up the line and low voltage to the system. When all
devices are powered, the thermostat should detect the indoor and outdoor units
within 45 seconds.
15.0 CHECKING AIRFLOW
The air distribution system has the greatest effect on airflow. The duct system is
totally controlled by the contractor. For this reason, the contractor should use only
industry-recognized procedures.
The correct air quantity is critical to air conditioning systems. Proper operation, effi-
ciency, compressor life, and humidity control depend on the correct balance
between indoor load and outdoor unit capacity. Excessive indoor airflow increases
the possibility of high humidity problems. Low indoor airflow reduces total capacity,
and causes coil icing. Serious harm can be done to the compressor by low airflow,
such as that caused by refrigerant flooding.
Heat pump systems require a specified airflow. Each ton of cooling requires
between 340 and 450 cubic feet of air per minute (CFM).
Duct design and construction should be carefully done. System performance can be
lowered dramatically through bad planning or workmanship.
Air supply diffusers must be selected and located carefully. They must be sized and
positioned to deliver treated air along the perimeter of the space. If they are too
small for their intended airflow, they become noisy. If they are not located properly,
they cause drafts. Return air grilles must be properly sized to carry air back to the
blower. If they are too small, they also cause noise.
The installers should balance the air distribution system to ensure proper quiet air-
low to all rooms in the home. This ensures a comfortable living space.
These simple mathematical formulas can be used to determine the CFM in a resi-
dential or light commercial system.
Electric resistance heaters can use
CFM =
volts x amps x 3.414
1.08 x temp rise
Gas furnaces can use
CFM =
BTUH
∆
T x 1.08
An air velocity meter or airflow hood can give a more accurate reading of the sys-
tem CFM’s.
16.0 CHECKING REFRIGERANT CHARGE
Charge for all systems should be checked against the Charging Chart inside the
access panel cover. Before using the chart, the indoor conditions must be within
2°F of desired comfort conditions and system must be run until operating conditions
stabilize (15 min. to 30 min.)