5.1 OPERATION
Operating principal-
The dryer models described in this manual operate all on the same principal. The hot moisture laden air enters an
air to air heat exchanger. The air then goes through the evaporator, also known as the air to refrigerant heat exchanger. The
temperature of the air is reduced to approximately 35-39 degrees Fahrenheit, causing water vapor to condense to liquid. The liquid is
continuously coalesced and collected in the separator for removal by the condensate drain. The cool moisture free air then passes back
through the air to air heat exchanger to be reheated to within fifteen degrees of the incoming air temperature as it exits the dryer.
Refrigerant circuit
- Refrigerant (R-134a) gas is cycled through the compressor and exits at high pressure to an air condenser where
heat is removed causing the refrigerant to condense to a high pressure liquid state. The liquid is forced through a metering device
(capillary tube) where the resulting pressure drop allows the refrigerant to boil off at a predetermined temperature. Low pressure liquid
refrigerant enters the heat exchanger where heat from the incoming air is transferred causing the refrigerant to boil, the resulting phase
change produces a low pressure, low temperature gas. The low pressure gas is returned to the compressor, where it is re-
compressed and begins the cycle again. During those periods when the compressed air load is reduced the excess refrigerant is by-
passed automatically back to the compressor via the hot gas by-pass valve circuit.
5.5 AIR/REFRIGERANT FLOW DIAGRAM NCIM10-NCIM18
4
3
9
10
7
8
13
5
M
1
11
6
ELE
12
2
12
14
ELE
1
Refrigeration compressor
8
Condensate separator
2
Condenser unit
9
Condensate drain valve/strainer
3
Solid filter drier
10
Condensate drain solenoid valve
4
Capillary tube
11
Condenser unit fan
5
Evaporator - Air-to-refrigerant heat exchanger
12
Electronic controller – DMC5
6
Hot gas by-pass solenoid valve
13
DewPoint temperature probe
7
Air-to-air heat exchanger
14
By-pass system (optional)
Air flow direction
Refrigerant flow direction
