Daily Maintenance of Refrigerated Air Dryers
Observe and record instrument readings 4 times per shift
Pressure difference between compressed air inlet and outlet shall not exceed 0.035 MPa;
Refrigerant low-pressure gauge: 0.3 MPa ~ 0.5 MPa;
High-pressure gauge: 1.2 MPa ~ 1.9 MPa.
(2) Regularly inspect drainage and blowdown system
If the electronic drain valve operates normally but no water is discharged, the filter screen is likely clogged and needs cleaning.
Close the ball valve at the front of the drain valve.
Press the test button to release residual compressed air.
Unscrew the filter screen plug and take out the filter screen.
Soak the filter screen in soapy water for about 10 minutes, then rinse with clean water (or blow clean with treated compressed air).
After cleaning, reinstall the filter screen and plug, then open the front ball valve.
If the solenoid valve leaks without component damage, a large amount of powder in condensate may pass through the filter screen and enter the gap between the valve spool and sleeve,
causing the spool to jam. The valve spool needs to be cleaned.
Cut off the power supply of the drain valve.
Remove the coil, unscrew the hex nut, take out the valve spool and two springs. Clean the valve seat, spool, springs and spool sleeve, then reassemble all parts.
Note: The electronic drain valve must be powered off before removing the coil. Otherwise, the energized coil will burn out once separated from the valve stem.
(3) Regularly monitor inlet temperatures of cooling water system and compressed air system
Cooling water temperature: 2 ~ 32°C;
Water pressure: 0.15 ~ 0.3 MPa;
Compressed air inlet temperature generally ≤45°C (it should not feel hot when touching the inlet pipe by hand; exceptions apply for special conditions).
Keep cooling water clean. Clean the Y-type strainer every half month; once per month if water quality is good. Clean the water-cooled condenser annually.
Clean the air-cooled condenser every month.
When cleaning the air-cooled condenser, avoid bending the condenser fins.
Sufficient space for ventilation and heat dissipation shall be reserved around the air-cooled condenser; avoid operation under direct sunlight.
Periodically blow off surface dust with compressed air. Do not use excessive flow and pressure of cleaning air.
Cleaning procedure for shell-and-tube water-cooled condenser: Close cooling water inlet and outlet valves, remove the end cover without water piping.
Only clean the outer surface of the end cover and gaskets with water. Clean the inner copper tubes with gas,
water or a stick wrapped with cloth. Do not apply excessive force during cleaning to prevent rupture of internal copper tubes.
(4) Regularly inspect the refrigeration system
Touch the compressor by hand at least once every day. Normal condition: cold surface with frost formation.
Check the temperature difference on both sides of the filter drier every week. The temperature difference should not be significant. If the inlet is hot and the outlet is cool, the filter drier needs replacement.
Contact after-sales service promptly if abnormal noise or overheating of the compressor is detected.
(5) Inspection of electrical control system
Blow away dust and fasten wiring terminals. All operations must be carried out with power disconnected.
(6) External Maintenance
Wipe oil stains and dust on the equipment surface regularly with a clean cloth. Remove dust and oil from the floor where the refrigerated air dryer and air compressor are installed to maintain a tidy environment.
