
MVT26
October 2003
Section 3
Page 59
3.2.1.1
Compressor Operating
The normally open solenoid valve (1) controls the condensate draining of the 2nd stage intermediate sep-
arator (2). The normally open 3rd stage condensate drain valve (4) controls the condensate draining of the
3rd stage intermediate separator (3). The normally open oil and water separator condensate drain valve
(5) controls the condensate draining of the oil and water separator (6). The control air for the 3rd stage
condensate drain valve (4) is taken from the 2nd stage intermediate separator (2). The control air for the
oil and water separator condensate drain valve (5) comes from the 3rd stage intermediate separator (3).
As the compressor is started, the solenoid valve (1) is electrically energized and closes. This allows the
pressure to buildup in the intermediate separators (2 and 3). This pressure buildup results in control air
closing both condensate drain valves (4 & 5).
3.2.1.2
Condensate Draining
Every 15 minutes the timer deenergizes the solenoid valve (1) for approximately 6 seconds. The solenoid
valve (1) opens and drains the condensation from the 2nd stage intermediate separator (2). Due to the
pressure loss in the 2nd stage intermediate separator the control air for the 3rd stage condensate drain
valve (4) is also removed. As the pressure of the control air is dropping, the piston of the 3rd stage con-
densate drain valve (4) becomes unloaded and the remaining control air is vented through a relief port.
Then the piston of the drain valve is fully raised by pressure from the 3rd stage separator, and the conden-
sate is drained. This in turn causes a pressure loss in the 3rd stage intermediate separator (3) and the con-
trol air for the oil condensate drain valve (5) is removed and the oil and water separator condensate drain
valve opens and drains the oil and water separator (6).
Figure 3.2-2
ACD Operation Diagrams
1. Solenoid Valve
2. 2nd Stage Intermediate Separator
3. 3rd Stage Intermediate Separator
4. 3rd Stage Condensate Drain Valve
5. Oil and Water Separator Condensate Drain Valve
6. Oil and Water Separator
Normal Operation
Condensate
Control Pressure
1
2
3
4
6
5
Condensate Draining
Condensate
Control Pressure
3
2
6
5
4
1