Howden wrv163 lube oil pressure

[RANGER1]

In service since 2013, runs most of the time. Hardly any drop across oil filter. Oil level in separator 40 to 50 %. Oil dp use to be 40 plus, but has gradually decreased and now at 30 to 32 psid. But to maintain that the discharge pressure setpoint was lowered from 160 psig to 150 psig. LOPD alarm set at 28 psid. I did slowly close off the bypass to see if there was any overflow and no change in pump pressure. Last oil sample had a small amount of ferrous wear like the previous samples (8 to 11 ppm). Probably going to suggest a compressor inspection (or rebuild) which HOWDEN recommends after 4 years (not my specialty)!

Any chance of a few pictures of compressor nameplate, oil going into compressor & oil pump?

LOPD is it just an alarm? or do you mean compressor stops on this.

Has oil temperature always been 130F?
Is oil cooler water cooled, has it been serviced, cleaned etc.

Is there any other relief valves in oil system after pump?

Has anything else changed over the last year, like problem started after a service like oil change or production change?

As Tycho instructs, says close oil injection a bit & problem will be probably solved.
See what it's set at first, then make adjustment.
I don't think it even needs it, not sure on 163, but all other WRV is injected under shaft seal area.

8-11 ppm iron is nothing as long as it stays at similar reading over time.
Ok something has changed but LOPD to high weather it's alarm or trip, can you adjust it down
it's still very safe.

[Tycho]

Any chance of a few pictures of compressor nameplate, oil going into compressor & oil pump?

LOPD is it just an alarm? or do you mean compressor stops on this.

Has oil temperature always been 130F?
Is oil cooler water cooled, has it been serviced, cleaned etc.

Is there any other relief valves in oil system after pump?

Has anything else changed over the last year, like problem started after a service like oil change or production change?

As Tycho instructs, says close oil injection a bit & problem will be probably solved.
See what it's set at first, then make adjustment.
I don't think it even needs it, not sure on 163, but all other WRV is injected under shaft seal area.

8-11 ppm iron is nothing as long as it stays at similar reading over time.
Ok something has changed but LOPD to high weather it's alarm or trip, can you adjust it down
it's still very safe.

PLEH2EREH: Since you said the oil dP has gradually decreased over time, it suggest that there might be underlying reasons other than the oil injection being full open.
if someone had opened them one day, you would have noticed an immediate and sudden drop.

I'd also like to have answered the questions Ranger asked, because I have had similar issues and have had great help from Ranger.

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