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13-17-609 Page 51
5-6
COMPRESSOR OIL FILTER
- The oil filter is a vital part in maintaining a trouble-free compressor, since it
removes dirt and abrasives from the circulated oil. It should be replaced every 1000 hours of operation
and when the oil is changed.
A bypass valve, mounted within the oil filter element, provides uninterrupted oil flow when the pressure
drop exceeds 25psid
– this is typical behavior for a contaminated element or one exposed to viscous oil
during a cold ambient startup. An external pressure switch monitors the same pressure drop and opens
between 12 to 18 psid, triggering an advisory message on the AirSmart controller display
– See controller
manual 13-17-600, advisory #320, for further details. The pressure switch also includes a red, auto-
resetting, pop-up visual indicator that confirms a triggered condition.
Note that a dirty oil filter may continuously open its internal bypass valve and introduce unfiltered,
contaminated oil into the compressor. It is critical that corrective action is taken once indication of a high
pressure drop condition is evident.
Improper oil filter maintenance will cause damage to equipment. Replace filter
element every 1000 hours of operation. More frequent replacement could be
required depending on operating conditions. A filter element left in service too
long may damage equipment.
The filter media is contained within an easily replaced, spin-in assembly that shares a common housing
with the oil mixing valve
– See Figure 5-1 for details. Use the following procedure to replace the filter. Do
not disturb the piping:
1. Be sure the unit is completely off and that the oil reservoir is depressurized.
2. Disconnect lockout and tagout the power supply to the compressor package.
3. Unscrew the oil filter using a 1
” socket and remove.
4. Rotate the filter head (aluminum assembly) to align the channel in the head with the tabs on the oil
filter element, lift the threaded part of the filter head until it is seated against its top, and remove the
oil filter element away from the oil filter head.
5. Install the new oil filter element if reverse order.
6. Press the oil filter assembly into the housing, and using the 1
” socket, tighten down until the o-rings
seat within the housing. Do not over tighten.
7. After the compressor is started and pressurized, inspect housing-to-element joint for leaks.