Efficient Multi Split AC Condensing Units provide advanced cooling solutions with multiple compressors and independent refrigerant circuits. Designed for various fan coil units, these units are factory-packaged for easy installation, featuring robust components like copper piping, brazed connections, and leak-tested refrigerant circuits. They include high-performance condenser coils, centrifugal blowers, and comprehensive safety controls for reliable operation. Ideal for diverse applications, they offer efficient cooling with minimal maintenance requirements.
Overview of Multi Split AC Condensing Units
The multi-split condensing units shall be with multiple compressors, each with its own independent refrigerant circuit couple with selected fan coil units (wall mounted, ceiling concealed, ceiling cassette or ceiling exposed type). Multi split units are completely factories packaged, wired and provided with shut off valves for convenient connection to the suitably selected direct expansion fan coil units. Each refrigerant circuit of this package shall be constructed using copper piping with brazed connections; joining compressor, condenser coil, filter drier, sight glass, thermo-expansion valve and evaporator cooling coil in a completely sealed loop. The refrigerant circuit shall also be factory leak tested, dehydrated, evacuated and pre-charged with R-22. The air-cooled condensing section shall consist of the compressor(s); condenser coil; centrifugal condenser fan(s) with motor and drive assembly, factory packaged switchboard, safety and operating controls.
The evaporator blower section shall consist of the direct driven centrifugal blower fan and motor assembly; direct expansion coil complete with thermo-expansion valve(s), remote controller and a filter frame for flat filters.
Air-Cooled Condensing Section
Casing
All steel parts shall be coated with epoxy-acrylic electro-deposition (ED) paint. Prior to ED coating, the part shall undergo a complete pre-treatment process, which involves de-greasing, phosphating and rinsing with de-ionized water.
Compressor(s)
Compressors shall be of sealed hermetic rotary, reciprocating or scroll type, with suction gas-cooled motor, internal suspension system to eliminate vibration, internal line or solid state protection and external crankcase heater. Unit shall have multiple compressors and each shall have its own independent refrigerant circuit and controls. Compressor shall also be pre-charged with oil.
Condenser Coil(s)
Each coil shall consist of staggered row of 3/8″ OD seamless copper tubes, mechanically expanded into die-formed corrugated hydrophilic coated aluminium fins. Each coil shall also be provided with integral sub cooling circuit. Coils shall be leak and pressure tested to 450 psig.
Condenser Blower(s)
The condenser fans shall be centrifugal types. Fan shall be statically and dynamically balanced and shall be mounted on a solid steel shaft running in self-aligning ball bearing, amply sized for quiet operation and long life. The condenser fan shall be driven directly by a resiliently mounted squirrel cage induction motor with adequate horsepower for the day.
Factory Packaged Switchboard
The multi-split condensing unit shall be completed with built-in factory wired starters for compressors, condenser fan motor, indicating lights, line fuses, isolator and interlocking points for fan motors of evaporator blower unit. Factory packaged starters for compressors shall be direct on line type.
Safety Controls
High pressure and low-pressure cutouts to guard against compressor damage due to high discharge head pressure and system leakage respectively shall be included. Crankcase heater for each compressor and anti-recycling timer shall also be provided.
Evaporator Blower Section
Evaporator Coil(s)
Each coil shall consist of staggered row of seamless copper tubes mechanically expanded into die-formed corrugated hydrophilic-coated alluminium fins, spaced 12 per inch. The direct expansion coil(s) shall have one or multiple independent refrigerant circuits each with its own thermo-expansion valve. Each coil shall be leak and pressure tested to 450 psig, evacuated and pre-charged with a small holding charge of R-22.
Blower
Centrifugal blower(s) of forward curved multi-blade type shall be fitted to the air conditioning unit. Blower shall be statically and dynamically balanced and shall be rust proofed. Blower shall be run on a common shaft mounted on self-aligning bearing. Bearings shall be sized for load imposed and shall be either permanently lubricated type or fitted with accessible greasing points.
Remote Controller
LCD wireless remote controller shell be operated in 3 operation modes (cool, dry and fan), fan speed control (Low/Med/High/Auto), 24 hours auto start/stop timer and clock, and on/off air swing control.
Pros & Cons
Pros:
- Efficient cooling with multiple compressors
- Robust construction
- Versatile installation options
Cons:
- High initial cost
- Potential coolant compatibility issues
FAQ
What types of fan coil units are suitable for multi-split condensing units?
Multi-split condensing units are suitable for wall-mounted, ceiling-concealed, ceiling cassette or ceiling exposed fan coil units.
How are refrigerant circuits of multi-split units constructed?
Refrigerant circuits are constructed using copper piping with brazed connections, including components such as compressors, condenser coils, filter driers, sight glasses, thermo-expansion valves, and evaporator cooling coils.
What safety features are included in multi-split condensing units?
They feature high-pressure and low-pressure cutouts, crankcase heaters and anti-recycling timers to ensure safe and efficient operation.
Conclusion
Efficient multi-split condensing units provide reliable cooling solutions for a wide variety of applications, combining advanced technology with robust construction. Despite their initial cost and potential challenges with refrigerant compatibility, they offer efficient performance and ease of installation, making them a preferred choice for a variety of refrigeration needs.