Help needed with Ipac DX Downflow Unit

[mr slim]

Hi guys

I got called out to a Comms Room with 2 of these Ipac IP 30 Dx downflow units installed. The job is approx 2 years old and the customer tells me there been an ongoing issue with them since day one including refrigerant leaks.
The room temp is a little higher than usual one side so i checked the unit over.
The system operates on R407c.

I am getting:-

Air on to indoor @ 24c
Air off indoor @ 16c at best 15.8c
Suction pressure fluctuating between 5 and 6 bar
superheat taken from evap outlet between 8 and 11k
No temp drop across filter drier
Air on to outdoor coil was 12c
Air off 37c
High side at Remote condenser inlet fluctuating between 18 and 19 bar by speed controller.
sub cooling taken at remote cond outlet between 9 and 11k
Sight glass clear but flashes intermittently.

Any help would be appreciated.

Thanks

[bobjob]

It looks like S.O.G.

But I need to know more- Does the unit have EEVs and how is the condenser fan controlled ?

Bob

[mr slim]

Hi Bob

Its got a Danfoss TEV and the speed controller is a saginomiya

[The Viking]

Hmm,
9 to 11 K subcooling, personally I wouldn't start looking for a short of charge issue. Intermittent flashes in the sight glass is fairly normal and nothing to be too hung up on.

1 Bar variation on the suction pressure and 3 K on the superheat? There is something going on there... An issue with the TEV, maybe it need adjusting? Or could there be an imbalance of the R407c? When the leaks were repaired, was the total charge replaced with virgin refrigerant or was it topped up? Or is the humidity in the room too low, below the unit's spec?

Now, delta T of 8ºC with air supplied at 16ºC... What are you looking for? What does the spec say? Could it be as easy as an over load issue?

:cool:

[install monkey]

http://www.mediafire.com/view/?3dxdauwd964emwz
ipac manual- got piccys in it too!!:)

[mr slim]

Great thanks for the manual !!! there none on site.
We have just took this contract on and apparently there have been issues with this unit having gas leaks. My thoughts were maybe that the composition of the refrigerant wasn't right. I did try adjusting the valve but it did not seem to make much difference.
It seems like one side of the room has more or bigger servers with higher heat output than on the other side so it could be possible that it is overloaded.
IT amazes me that they put millions of pounds of equipment in these server rooms then never bother installing back up units in case one system fails.