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View Full Version : How many hours can a Bitzer screw run for?



RANGER1
15-09-2011, 08:39 AM
Installed a Bitzer OSKA semi-hermetic screw just under 14 yrs ago.
Its on a glycol chiller with PHE evapaporator & condensor on R22.

It has run continuously for that time (approx 120000 hrs), except for maintenance of course.

It has also condition monitoring with no signs of bearing deterioration,
it sounds like the day we put it in.

It also has standard Bitzer oil filter.

We changed compressor over with the spare for site which is also 14 yrs old,
to give used one a rest & to make sure spare is OK.


Can anyone advise on similar or better records?

I think this one could have lasted forever!

Grizzly
15-09-2011, 05:35 PM
Hall screws have a 25 yr maintenance schedule, in fact if I remember correctly it says something like after 25 years check main bearings for wear!

Screws like a constant load the smoother the better.
Can't fault the bitzers I deal with, good kit.
Grizzly

Magoo
16-09-2011, 01:03 AM
Hi Ranger1
wow that is an amazingly good run, I generally pull them out at 30K hours and have them striped and checked, must admit there never much wrong with them. Generally everything within spec.,

goshen
16-09-2011, 02:23 PM
Hi
wow is the word!!
and they say it is hard to stop a trane!!
have quite a few bitzer comps,been running for approx 7 yrs also no known problems !
keep up the good maintenance.

Jahangir
26-09-2011, 11:49 AM
Hi all, I think it is big record but if it is available please send information of environment temp. and Evaporator temp.

thamks

RANGER1
26-09-2011, 10:27 PM
Hi all, I think it is big record but if it is available please send information of environment temp. and Evaporator temp.

thamks


Jahangir,
This very small packaged unit on R22 runs at -6 SST +40 SDT.
The 40 deg C condensing is because of water cooled condensor in tropical area.
Has a Danfoss electronic expansion valve.