PDA

View Full Version : wihch is the best



liamroys
03-02-2007, 01:27 PM
:) Hi all, long time not visited, any advice on this one appreciated. a 10kw unit is wanted in an IT server room, to do all the work. a 6kw Daikin is in as a back up. which is the most reliable manufacturer around?

LRAC
03-02-2007, 02:08 PM
:) Hi all, long time not visited, any advice on this one appreciated. a 10kw unit is wanted in an IT server room, to do all the work. a 6kw Daikin is in as a back up. which is the most reliable manufacturer around?

Not sure what other members think but we only install mitsubishi electric, took us a long time to find a reliable manufacturer.

Regards
Lrac

Latte
03-02-2007, 02:12 PM
Daikin Up there everytime, very closely followed by Mitsi Electric.

However, These days most of the Medium range priced units are ok, The only thing i would say as its a server room stick clear of LG. Too many problems with them over the last few years and until someone tells me they have once ond for all sorted out the pipeing problems i would stay away

Regards

Fatboy

nui
03-02-2007, 06:33 PM
Talk to Mitsubishi Heavy Industries, not Mitsubishi Electric. They have,from memory, 3 models that can handle the high sensible heat loads needed for a comp room. They use them in gsm towers in Australia (some companies)

Peter_1
03-02-2007, 08:38 PM
Daikin Up there everytime, very closely followed by Mitsi Electric.


Uhhh, Mitsubishi followed by Daikin do you mean ;) :p :D

gwilliamson
03-02-2007, 09:58 PM
We regulary use fujitsu, Mitsi Heavy, Toshiba & Hitachi. Hard to tell the difference as rate all of them very highly. If its a small server room must recommend the Hitachi as comes a standard with low ambient.
Must admit find it hard to sell Daikin as a premium because have not really found a good reason for the inflated prices?!.
Thoughts on this really appreciated.

Obi Wan
03-02-2007, 10:51 PM
Hello Liamroys,

I guess any of the major manufacturers will be good enough. But you should look at other aspects for the install.

For the customer;
Choose a unit that is listed in the governments “Enhanced Capital Allowance” scheme http://www.eca.gov.uk (http://www.eca.gov.uk/) The customer can offset the cost of the equipment against his tax liability. However you will have to install a Heat Pump even though the application is cool only.

For the environment;
Choose an inverter driven system.

For the control;
You already have a Daikin system, install a new Daikin system as Lead Lag, Duty Standby interface will be easer to achieve for two system from the same manufacture.

Check out the RZQ___B Daikin sky air inverter system, it ticks all the boxes above.

Regards

Obi Wan

NoNickName
04-02-2007, 01:52 PM
No. Install a Close control unit, not a split system.
Daikin, Mitsi, Fujitsu and the like DO NOT produce close control units.
Brands: Uniflair, RC, Liebert-Hiross, Montair

Peter_1
04-02-2007, 02:42 PM
Specs are mostly not that stringent so that you don't need a CCU.
Practice has shown alreayd so many times that it can be done with a normal split for a lot less money then a CCU.
Installed a VRF for the server and IT room of a big hospital here nearby, splits for the communciation center of the Belgium Parliament, years ago and still running.
But this discussion was already made in the past.

TSK
05-02-2007, 12:33 AM
Check how much current is being drawn by the computer equipment at the mains and divide by 4 the result will be the kw of sensible load in the room, don't forget the A/C cooling rating is total (including the bit doing nothing more than removing moisture) and then select your desired supplier, make sure there is built in ambient control as the unit will still be cooling when it's freezing outside. Poor energy useage but who is going to pay for a system that can use free cooling unless it's a big server room!

NoNickName
05-02-2007, 08:39 AM
Check how much current is being drawn by the computer equipment at the mains and divide by 4 the result will be the kw of sensible load in the room,

This is breaking news to me.
Always thought that 95% of current drawn by PCs is heat, doing nothing but standing still.

Peter_1
05-02-2007, 08:58 AM
NoNickName, I think he's correct with this calculation - I'm doing it the same way - on a net of 240 V.
If you have 2400 W, then it will draw 10A, if you divide this roughly by 4, then you become 2.5 kW.

NoNickName
05-02-2007, 09:42 AM
Well, I misinterpreted. It's obvious that Power = Voltage x Current, and by chance 240V is approx 1/4 of 1kV.
I understood that the cooling capacity required is 1/4 of the power absorbed by equipment, which is of course long way wrong.

nebbie67
06-02-2007, 05:38 PM
Mitsubishi Electric, and of course, Daikin.

liamroys
10-02-2007, 05:33 PM
Thanks to all for the advice, much appreciated:)

The Viking
10-02-2007, 06:14 PM
Short note that been covered earlier in the thread but is worth repeating/highlighting:

Look at the sensible capacity of the system you propose to install. This varies a lot between different manufacturers. (Daikin normally coming out the lowest)

There are some units that will let you lock them in to 'cooling only' and set a fixed set-point, this reduce the risk of clever IT guys messing around with them.

Other than that it's not much between the more reputable brands that will differ, they will all be up to the job.



:cool:

liamroys
27-02-2007, 09:28 AM
Hi again, thanks for all advice. availability became one deciding factor, rang Daikin for a 10Kw inverter only to be told they were out of stock for 2 weeks

we have got a Tosh 12kw inverter running 2 indoors now and it's positively freezing.

:cool:

Quality
27-02-2007, 08:03 PM
Stay away from LG & Carrier, if my past nightmares are any giude.:)

KayPoh
28-02-2007, 05:08 AM
Stay away from LG & Carrier, if my past nightmares are any giude.:)

Appreciate it very much if you can elaborate what are the nightmares with Carrier.
Over at my place Carrier (apply to split systems) is not popular.

Quality
28-02-2007, 12:21 PM
Achieving the specified duty that they are supposed to provide even when calculated & specified by them on either cycle but more often when used on heat which doesn`t add up:)

Andy W
02-03-2007, 08:41 AM
Check how much current is being drawn by the computer equipment at the mains and divide by 4 the result will be the kw of sensible load in the room, Not heard that one before. I presume you are talking of amperage of the all computer related kit only?