Outdoor air cooled condensing units a space-saving air conditioning in commercial buildings and homes. Air-cooled units and save the cost of piping water circuits. They are also used where chemical substances in the water of water cooling is impractical. These blocks can be installed on the roof, wall, or at ground level.
Air-cooled condensers must have four major provisions:
There must be a head pressure control if the device is exposed to outdoor weather conditions, which may go below the operating temperature inside the Cabinet.
A method to prevent short Cycling must be designed into the system.
Means should also be provided to prevent dilution of the compressor oil with liquid refrigerant.
Filled capacitor should be built and
installed virtually weatherproof. At low ambient temperatures will lead to low head pressure. This pressure may drop so low it can even stop the flow of refrigerant. Four different methods of maintaining reservoir pressure:
Partially fill capacitor with liquid refrigerant.
To stop or slow down the condenser fans.
Partially or completely close the ambient air blinds.
Heat in the condenser.
outdoor units require about 1000 cfm (cubic feet per minute) condenser air circulation per horsepower.
They are less costly to operate than indoor air-cooled units. Dual compressor model has two completely separate refrigeration systems. They range from 6 tons to 35 tons, and provide what is called a partial system standby. Basic operation is a two-stage compressor, with each compressor enabled separately from the two-stage space thermostat. This provides a two-stage cooling and two-stage heating system, automatic switching.
Basic operation is as follows: No. 1 turns on the first stage unit. If the load is light, the system carries the load. Compressor cycle on and off when you call a thermostat. An example of this can be cool in the morning, late at night, cloudy days, etc. that It will lead to the thermostat signal compression cycle.
No, 1 may not be sufficient to handle the load. In this case, the room thermostat, automatically switches to the second compressor. Then the signal is switched on and off to carry the rest of the load, and the Compressor 1 is running, remove moisture from the air. When the load drops and a decrease in the temperature of the object, Compressor 2 is disabled. Compressor 1, and then cycles carry the load reduction.
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