11
Compressor
d
elay PCB
Fig.5-1
START KITS(OPTIONAL)
This special relay uses the EMF generated by the compressor start windings to take a start capacitor out
of the circuit. The relay and its companion capacitor can start the compressor at low voltages and
against higher pressure, such as those caused by non-bleed port expansion valves.
compressor make a start kit unnecessary.
Start kit components should match the recommended ratings and functions of those provided by the
Start kits are not normally required with scroll compressors. The operating characteristics of the scroll
reciprocating compressor manufactorer. See Specifications start components.
Before specifying any air conditioning equipment, a survey of the structure and a heat gain calculation
The cooling load calculation determines the unit size. There are two capacities that enable the
must be made. A heat gain calculation involves identifying all surfaces and openings that gain heat from
the surrounding air and quantifying that heat gain. The heat calculation also calculates the extra
heaty load caused by sunlight and by humidity removal. These factors must be considered before
selection an air conditioning system to provide year round comfort. The Air Conditioning Contractors
cooling load.
6. APPLICATION
of America (ACCA) J Manual method of load calculation is one recognized procedure for determining the
Sensible heat is the heat energy
measured on the dry bulb thermometer.
equipment to provide comfort. The first is sensible capacity.
.
After the proper equipment combination has been selected, satisfying both sensible and latent
The second form of heat is called latent heat. This is heat held by the moisture in the air. Removing
this moisture does not affect a thermometer. However, removing the latent heat in the air greatly increase
comfort. A properly sized unit removes both forms of heat, producing a comfortable conditions,
An oversized system cycles on and off quickly and does not properly remove humidify, producing
uncomfortable. The indoor and outdoor equipment combination should be matched by the manufacturer
and based on engineering data.
conditioning requirements, the system must be properly installed. Proper installation with cerefully
distributed air through adequate duct work will provided a comfortable living space.
There are several factors that installers must consider.
ƽ
Outdoor unit location
ƽ
Proper equipment evacuation
ƽ
Outdoor unit refrigerant charge
ƽ
Indoor unit air flow
ƽ
Indoor unit blower speed
ƽ
Supply and return air duct design and sizing
ƽ
System air balancing
ƽ
Diffuser and return air grille location and sizing
Central Air Conditioner
Model: Cooling Only,
13
SEER
units
