13-18-601 Page 48
•
The lubricating and cooling oil must be kept at a normal operating temperature below 225
°
F in order
to preserve its longevity.
•
The compressed air supply must be delivered into the distribution system at a temperature not
exceeding 15
°
F above the ambient level in order to protect other devices (e.g., filters, dryers, tools,
etc) against damage. At 100 psi of discharge pressure, the air core allows the flow of 427 cfm with
1.1 psid pressure loss.
AIR-COOLED HEAT EXCHANGERS
– Air-cooled cores (radiator-type) are provided as standard feature.
Axial fans (one on VS45, two on VS50 and VS70), located below the heat exchangers, pump the required
amount of cooling air and expel it through an opening on the enclosure roof. Each fan is driven by a
close-coupled, IP54-protected, electric motor. A common full-voltage starter energizes the fan motors.
Refer to Figure 6-1 for estimates of ventilation requirements. Please note that the air-cooled package
requires the combined total of the heat exchanger plus the enclosure ventilation flow rates (which include
motor ventilation and compressor intake). Furthermore, when package location makes it necessary to
duct fresh cooling air in/out, these ducts must be sized with a maximum (total) pressure loss of .1 inch
water gauge to avoid impacting the heat exchanger cooling air system. An external ventilation fan may
be required to properly evacuate hot air from the compressor room.
Minimum Cooling Air Flow Requirements
CFM
KW
Air-Cooled
Heat
Exchangers
Enclosure
Ventilation
Fan
45 5200
1600
50 8223
1600
70 8223
1600
Figure 6-1 – AIR FLOW CHART
All the required hardware, mechanical and electrical connections have been made at the Gardner Denver
factory, thus the only regular maintenance required is to keep the exterior core fins free from dirt and
other airborne debris per the following procedure:
Air-cooled heat exchanger cores are fabricated from aluminum. Do not use
caustic liquids to cleanse core or permanent damage will take place.
1. Be sure the unit is completely off and that oil reservoir is depressurized.
2. Disconnect, lockout and tagout power supply to the compressor package.
3. Open and/or remove enclosure door panels adjacent to cooler assembly.
4. Locate cooler housing side covers (See Figure 6-2) and remove by unscrewing fasteners.
C
C
C
A
A
A
U
U
U
T
T
T
I
I
I
O
O
O
N
N
N
