Multisplits
You can run two or more indoor units from one condensing unit with economies in number and value components. Such systems are called multisplits, and several different types of print will meet. Split-package, air conditioning consists of one condensing unit, United pipes to one of the evaporating station. Two condensing units are manufactured save on outdoor buildings and reduce the number of pieces on the roof or wall. Such twins will be mounted in the usual way to two separate inner blocks.
Units with the same speed compressors will require some automatic method to shed the extra cooling power, when some of the fan-coil units do not require refrigeration. Fluid from the heat exchanger of the condenser runs directly through the expansion valve, and the resulting mixture is cold liquid and flash gas is distributed to each of the fan-coil units on a chain. On-off control a cold fluid in each room is effected by a solenoid valve within each inner box, which is activated via the room thermostat. Returned refrigerant gas, sometimes with unevaporated of the working fluid got into the suction traps, prior to entering the system, or the liquid boils in the suction/liquid heat exchanger.
As in the forward and reverse pipelines refrigerant fan-coil should be thoroughly isolated.
If any of the rooms do not require refrigeration, then the excess of the compressor capacity is taken up by injecting hot gas directly from compressor in reverse. Under low-load conditions Chapter pressure will drop, and this pressure should be supported by slowing the condenser fan. It may also be necessary to introduce some of the liquid in the return pipeline, if bypass gas makes it too hot. This system is used for cooling. The COP will be lower, than all the indoor units in action. Typical values with three interior units:
with 3 units of refrigeration COP = 2.2 2 blocks refrigeration COP = 1.6 1 block refrigeration COP = 0.9
Best balance between cooling capacity and the load can be obtained by capacity control compressor(s). Large system will have a number of compressors, or the built-in control power in the cylinders. Central condensing units of this type can be used in conjunction with multiple fan coil units, each with its own thermostat and fluid, electromagnetic value. The COP is good, but low levels of load.
The normal way of smaller units-thyristor regulator of speed of rotation of the compressor, and these compressors can be slowed down up to 40% of full speed or less. Some companies can operate at higher speeds than usual to cope with peak loads, but the COP will fall to this condition. Eight fan-coil units can be connected to each condensing unit and assigned amount can be nominally exceeds the capacity of the compressor, on the grounds that not everything will be cool at the same time...
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Air-Conditioning