Hitachi Screws

Good evening all,

Looking for some advice, Recently started a new job where I have to look after a site with 7 Climaveneta water chillers (in parallel)

Each Chiller has 4 Hitachi screws (40HP) and 2 evaporators.

According too guy servicing them before I started,
"2 compressors need gaskets replaced to repair leaks on chiller No. 3"

I dont have much experience on screws. I've just done a few service calls on them.

I'm presuming its the shaft seal that needs replacing(happened before I started), as the sparks on site has told me they've had leaks like this before.

The plant is 8 years old though. Are these compressors not supposed to be rebuilt every few years or so many hours.

It hasn't been happening here. What should i be lookin out for?:(

Hi CMAC,

give Pete a ring on 07970598116, he's the service manager for ACE, there's not many who know as much as him on Hitachi screws, as well as the chillers. He may be able to assist and no doubt carry out any necessary works. He also has at hand experienced and competant engineers for these compressors and chillers.
Hope this helps
PS The only gaskets that would require replacement are for the suction or discharge pipe flanges, oil filter plate, suction bell end, discharge separator housing or the terminal plate, you shouldn't need to touch anything internally.
Care has to be taken when pressure testing, the terminal plate will only take upto 13Kg/cm2 or 20Kg/cm2 depending on the age.
If the oil is ester, please check, this needs to be replaced and the system sealed within one hour as th is hydroscopic. Oil ideally needs to be poured in via the discharge port of the oil separator

Just noticed you're in Ireand, they also like Guiness!!!

Quote:

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Originally Posted by Inverter man

Hi CMAC,

give Pete a ring on 07970598116, he's the service manager for ACE, there's not many who know as much as him on Hitachi screws, as well as the chillers. He may be able to assist and no doubt carry out any necessary works. He also has at hand experienced and competant engineers for these compressors and chillers.
Hope this helps
PS The only gaskets that would require replacement are for the suction or discharge pipe flanges, oil filter plate, suction bell end, discharge separator housing or the terminal plate, you shouldn't need to touch anything internally.
Care has to be taken when pressure testing, the terminal plate will only take upto 13Kg/cm2 or 20Kg/cm2 depending on the age.
If the oil is ester, please check, this needs to be replaced and the system sealed within one hour as th is hydroscopic. Oil ideally needs to be poured in via the discharge port of the oil separator

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Thanks for the reply
Excuse the ignorance but should screws not be rebuilt after so many years or hours.

Still gonna use that number though. Does he like too travel:)

Hello Cmac hitachi screws are very good compressor, years back they needed bearing changes after 12000 hours on air cooled system and 20000 on water cooled systems . but the newer ones have long life bearings,i think you,ll have the 4005 series screw compressor which has metal gaskets, if the terminal post leaks then tighten it up but make sure the post doesnt move, other wise it will arch at the bottom of terminal plate. if you have any problems on gaskets or bearings send me a private message.

Thanks Inverter Man and ghaz. Appreciate it