LG in a Server Room - Compressor dead

[Makeit go Right]

I read with interest the problems one has to consider when putting a DX system in a Server/Comms Room, {http://www.refrigeration-engineer.com/forums/showthread.php?t=5926} and wanted to run this by these Boards in case anyone is familar with the LG unit and this kind of Server situation. The unit is a 5.2kW ASC186TLBO (410a) wall mounted unit. It was manufactured in May04, so presumably was installed by the end of that summer. The contactor was replaced in October 06The compressor died in December 06. The system is running, but I was curious about the selection - well, yes, it is an LG, but it is already installed, so we have to pass over that aspect. I wondered whether it would likely loose another compressor before too long, due to incorrect model selection, etc. Anyone familiar with this/these units?

[Brian_UK]

I don't know about 'incorrect selection' but another compressor failure is possible.

Do you know why the original compressor was replaced?

Was it due to a burn-out?

Was the system cleaned and filtered during/after the repair?

Was a 'proper job' done of the repair?

So many variables it's hard to say how long it will last.

[Latte]

Although i have done quite a few LG compressors i wouldnt say that they are a major problem. Most of them seem to have gone after units have had gas leak problems as recorded in previous posts.

However, When replacing a compressor i would say to take every precaution to protect the new one. Any sign of a burn out fit a bi-directional, Blow through with OFN, Good vac out with micron/torr gauge and hopefully you should be ok. Have had to also fit quite a few HP/Fan control kits on these units as they dont come with condenser fan control. Hawco sell they and they are a two min job to fit, otherwise in the middle of winter you can still have both condenser fans working and a stupidly low HP

Regards

Raymond

[The Viking]

As mentioned above, the big question is "Why did it fail?".

On a site we recently acquired, the previous mob had filled the server rooms with LG and Sanyo units (6 of them in one of the server rooms :eek: ).

After the customer signed us on but before we done the first service, we get the call "the Daikin unit in server room A doesn't cool at all and now the 2 LG units in the same room starts to freeze up".

Hmmmm.
One of our (Junior) engineers go to site (Don't ask, management's fault and we know it), towards the end of the day he calls me and tells me that he can't find a fault with any of the units. He has reclaimed the gas from both LG units and the charge were spot on, further more, now the Daikin has started to run again. But when he arrived both LG units had compressors covered in ice, the Daikin were cycling - 10 min ON and 20 min OFF.
At this point he hadn't changed anything and yet all 3 machines were working with all the right pressures/temperatures (He's good at checking that, he knows that I will beat him over the head with a spanner if he calls me and hasn't checked superheat/subcooling).

So I went in the day after...
Quick conversation with the customer confirms that this was a regular occurrence, it happened a couple of times each month and the previous engineer(s?) had come in, checked the units (as we did) and told them that they were working OK, but "you need another one mate, they aren't coping with the load"

My next step was to go in to the room with my trusted old whirlie, and yes, you guessed it, almost no humidity in the room at all (and an average temp of ~27).
As the customer is a bit sceptical at this point, I created a simple humidifier blue Peter style and told him that I would be back the day after and if the room wasn't working better then I would take him for lunch but if I were right he would buy some humidifiers from us.

We got the order for those humidifiers yesterday.

So why did the units react so different?
Turns out that the Daikin were cutting out on "Low coil/suction temp" but that the LGs hadn't got that function.

And why did the units work OK in the afternoon when our engineer hadn't done anything of value to them?
Well, guess what, whilst he were reclaiming he had the door open to get the extension lead through and to cool the room down.

So, in conclusion, one reason for a LG's compressor to fail (when Evap is fitted in a server room) is that the room humidity goes below what LG has designed the unit for.

[Abe]

So why did the units react so different?
Turns out that the Daikin were cutting out on "Low coil/suction temp" but that the LGs hadn't got that function.



This is an all important component which makes the differance with units operating within the vagaries of our northern climates.

Server rooms should only have the best systems fitted

[KayPoh]

Hi Viking,
When the RH was very low, did your client complains about static electricity?

[Gary]

So why did the units react so different?
Turns out that the Daikin were cutting out on "Low coil/suction temp" but that the LGs hadn't got that function.


Sounds to me like all three units are suffering from insufficient load/low coil temp/excess dehumidification, possibly as a result of insufficient airflow.

I'm not sure that adding latent load is the best solution. This has the humidifier and dehumidifier (function of the A/C) working against each other.

If the airflow cannot be increased to raise the coil temp, possibly EPR's would do the trick.

[The Viking]

Gary,
When I first heard about the issue of low humidity in comms room environment, I to were sceptical.
But, as they say, the proof is in the pudding.

For example, the room in the example above has a load of 15kW. Looking at the total sensible duty provided by the A/C units being almost twice that, there shouldn't be any reason for the units not to reach setpoint.
Before I raised the humidity, the temp stayed in the high twenties.
Now with a slightly higher humidity the units has no problem achieving 18 degrees (Oh, yes, but the IT manager has now been told and seen the light).

So even if humidity issues is a bit like religion, you are either a believer or not. I am convinced that it's true.

And Kay, no one complained about it to us but the guys who frequently worked in the room said that they always were thirsty after being in there.

[Latte]

I Assume it is therefore the same as when you have a/c on in youre van all day long, Now the Big Question is
WHATS THE SOLUTION TO GET THE HUMIDITY UP

Regards

Raymond

[The Viking]

I Assume it is therefore the same as when you have a/c on in youre van all day long, Now the Big Question is
WHATS THE SOLUTION TO GET THE HUMIDITY UP

Regards

Raymond

A humidifier????
:)

[Latte]

A humidifier????
:)

Very Good :rolleyes:

I meant, is there an a/c option. I am sure, whilst working for another company there was an a/c system installed at at museum that somehow also controlled humidity. Cant remeber the make, kept getting called out as the fan was belt driven and it kept breaking belts.
I assume anything like this costs a packet

Regards

Raymond

[Brian_UK]

I Assume it is therefore the same as when you have a/c on in youre van all day long, Now the Big Question is
WHATS THE SOLUTION TO GET THE HUMIDITY UP

Regards

RaymondMmmmmmm Beeer:cool:

[The Viking]

There are dedicated, full function units out there designed specifically for comms room applications.
But as far as I'm aware, they all has a "normal" humidifier inside them.

Brian,
Your idea of beer.......
In my youth (remember that I'm Swedish), we used to pour beer on the heater in the saunas, the result were that everybody inhaled the alcoholic vapour.
Now......
If we fill the humidifier with beer.......
That's an idea worth trying!

[Brian_UK]

Stop, I'm drooling

[KayPoh]

I Assume it is therefore the same as when you have a/c on in youre van all day long, Now the Big Question is
WHATS THE SOLUTION TO GET THE HUMIDITY UP

You can introduce some outdoor air into the room, presume the outside is humid.

[Dan]

I am confused. Do the server rooms require a certain amount of humidity? This could make sense to me due to the static electricity potential. But to introduce humidity into the room just to create a load for the compressor strikes me as absurd. What am I missing?

[KayPoh]

The thing is that we are using standard DX aircon system and it needs some latent heat as well to work. Usually there is air ingress into room through uncontrolled openings/gaps, etc which we don't notice.

[Gary]

Humidity is directly related to coil temperature. The colder the coil, the more it dehumidifies. Comm room units generally have very high airflow, to raise the coil temperature, avoid freezing the coil, and keep the humidity up.

As a rough rule of thumb, in order to maintain around 40-60% RH, the leaving air temp close to the coil should be about 20-22F (11-12C) lower than the desired room temperature. This varies a bit with coil design, but it gets you in the ballpark.

For 18C, you want a coil air off temp of about 6-7C. In many instances, this can be accomplished by adjusting the blower speed. The more airflow, the higher the air off temp... and vice versa. Another trick is to draw (warmer) return air off the ceiling to raise the air off temp.

[Electrocoolman]

There is a lot about server rooms in the following thread:

http://www.refrigeration-engineer.com/forums/showthread.php?t=5926

A lot of electronics, especially mainframe computers like to have a fairly constant humidity 40 -60% RH, as has been mentioned before, due mainly to keep static electricity at a minimum.

Cooling load in a computer / server room is a HIGH SENSIBLE Cooling load.
I believe with the Sanyo SPW range, one can connect an indoor unit of a larger 'capacity size' up and reprogram the indoor unit to match the lower capacity condensing unit. I think this then allows for a high sensible cooling load. These units will I believe provide cooling down to -15C outdoor ambient.

I would add that I have not done this personally, just recall it being mentioned on a recent training course.
Has anyone done this and does it work?

[Tomking]

Actually I am having a lot of problems with compressor faults like yours. Not done any LG yet. Our sales guru's have installed a lot of a leading european split makers kit in a few server rooms in 2005 and 2006. I found this site researching this.

Our supplier emailed me tonight saying there is a very good article in the RAC Service Engineer magazine that has just come out that explains why our compressors are faulting in server rooms.

I have to admit that we dont have any problems with the kit on any other sites that are normal installs. The boss blames the makers kit but listening to the supplier their story makes some sense. Last week they were talking a lot about fresh air we have to add. But their email now talks about raising the room temperature????!!!!!????

I've asked them to scan the article and email it tomorow.

[liamroys]

:) tttttttttttttttttttttt

[hendrag]

hi i run the lg tech support in the uk so hopefully i can help.
this unit is a non inverter budget wall mount, it never came with a fan speed control pvcb in the outdoor unit as standard so is completley unsuitable for comms rooms. Its operation range is only from +20 to +43 outdoor ambient. The pot will go down as the unit is overcondensing + the lack of latent heat in the room makes the indoor coil to small. A couple of suggestions 1 install a fan speeed controller when changing the pot + make sure the indoor fan seed is set to high and is not changed this will ensure the unit will have a long and happy life.

This is a common problem installers put budget units in comms rooms which they are not designed to operate in. Stick to inverter driven units in comms rooms as they have low ambient fan speed control as standard

good luck

hendrag

[Andy W]

This is a common problem installers put budget units in comms rooms which they are not designed to operate in. Stick to inverter driven units in comms rooms as they have low ambient fan speed control as standard

good luck

hendragThe reason installers put these poor quality sub standard machines into rooms was that their suppliers sold them to them for that application, only after I had installed a lot of LG's was I told that all of the LG wall mounts were aimed for the domestic market only, to run a max of 4 hours a day and totally unsuitable for any commercial application. I dont know how LG and there attrocious dealers can sleep at nights, my LG problems are too numerous to mention, thank god for Fujitsu!

[Karl Hofmann]

Price is also a major factor, time after time I quote to put Daikin inverters into server rooms only to discover that the customer has gone for the guy who is fitting an LG.. No competition really, the customer sees a beige box on the wall and asks whats the difference? Sure he'll find out soon enough but his money has gone and it's another lost sale.

[Abe]

hi i run the lg tech support in the uk so hopefully i can help.
this unit is a non inverter budget wall mount, it never came with a fan speed control pvcb in the outdoor unit as standard so is completley unsuitable for comms rooms. Its operation range is only from +20 to +43 outdoor ambient. The pot will go down as the unit is overcondensing + the lack of latent heat in the room makes the indoor coil to small. A couple of suggestions 1 install a fan speeed controller when changing the pot + make sure the indoor fan seed is set to high and is not changed this will ensure the unit will have a long and happy life.

This is a common problem installers put budget units in comms rooms which they are not designed to operate in. Stick to inverter driven units in comms rooms as they have low ambient fan speed control as standard

good luck

hendrag





SALES OF GOODS ACT 1979

14 Implied terms about quality or fitness

(1) Except as provided by this section and section 15 below and subject to any other enactment, there is no implied [term] about the quality or fitness for any particular purpose of goods supplied under a contract of sale.

[(2) Where the seller sells goods in the course of a business, there is an implied term that the goods supplied under the contract are of satisfactory quality.

(2A)
For the purposes of this Act, goods are of satisfactory quality if they meet the standard that a reasonable person would regard as satisfactory, taking account of any description of the goods, the price (if relevant) and all the other relevant circumstances.

(2B) For the purposes of this Act, the quality of goods includes their state and condition and the following (among others) are in appropriate cases aspects of the quality of goods—

(a) fitness for all the purposes for which goods of the kind in question are commonly supplied,
(b) appearance and finish,
(c) freedom from minor defects,
(d) safety, and
(e) durability.
(2C) The term implied by subsection (2) above does not extend to any matter making the quality of goods unsatisfactory—
(a) which is specifically drawn to the buyer's attention before the contract is made,
(b) where the buyer examines the goods before the contract is made, which that examination ought to reveal, or
(c) in the case of a contract for sale by sample, which would have been apparent on a reasonable examination of the sample.]
[(2D) If the buyer deals as consumer or, in Scotland, if a contract of sale is a consumer contract, the relevant circumstances mentioned in subsection (2A) above include any public statements on the specific characteristics of the goods made about them by the seller, the producer or his representative, particularly in advertising or on labelling.
(2E) A public statement is not by virtue of subsection (2D) above a relevant circumstance for the purposes of subsection (2A) above in the case of a contract of sale, if the seller shows that—
(a) at the time the contract was made, he was not, and could not reasonably have been, aware of the statement,
(b) before the contract was made, the statement had been withdrawn in public or, to the extent that it contained anything which was incorrect or misleading, it had been corrected in public, or
(c) the decision to buy the goods could not have been influenced by the statement.
(2F) Subsections (2D) and (2E) above do not prevent any public statement from being a relevant circumstance for the purposes of subsection (2A) above (whether or not the buyer deals as consumer or, in Scotland, whether or not the contract of sale is a consumer contract) if the statement would have been such a circumstance apart from those subsections.]
(3) Where the seller sells goods in the course of a business and the buyer, expressly or by implication, makes known—
(a) to the seller, or
(b) where the purchase price or part of it is payable by instalments and the goods were previously sold by a credit-broker to the seller, to that credit-broker,
any particular purpose for which the goods are being bought, there is an implied [term] that the goods supplied under the contract are reasonably fit for that purpose, whether or not that is a purpose for which such goods are commonly supplied, except where the circumstances show that the buyer does not rely, or that it is unreasonable for him to rely, on the skill or judgment of the seller or credit-broker.
(4) An implied [term] about quality or fitness for a particular purpose may be annexed to a contract of sale by usage.
(5) The preceding provisions of this section apply to a sale by a person who in the course of a business is acting as agent for another as they apply to a sale by a principal in the course of a business, except where that other is not selling in the course of a business and either the buyer knows that fact or reasonable steps are taken to bring it to the notice of the buyer before the contract is made.
[(6) As regards England and Wales and Northern Ireland, the terms implied by subsections (2) and (3) above are conditions.]
(7) Paragraph 5 of Schedule 1 below applies in relation to a contract made on or after 18 May 1973 and before the appointed day, and paragraph 6 in relation to one made before 18th May 1973.
(8) In subsection (7) above and paragraph 5 of Schedule 1 below references to the appointed day are to the day appointed for the purposes of those provisions by an order of the Secretary of State made by statutory instrument.


COMMENTS

I point you to Section 14 of the Act

Ok, it makes for heavy reading, but look carefully at the fitness of purpose rule

A system should be fit for the purpose of the application
If it is not designed for a server room, than it is not fit for that purpose.

[Makeit go Right]

Hi, I run the LG Tech Support in the UK so, hopefully, I can help.
This unit is a non-inverter budget wall mount. It never came with a fan speed control pvcb in the outdoor unit as standard, so is completley unsuitable for Comms Rooms. It's operation range is only from +20 to +43 outdoor ambient. The pot will go down as the unit is overcondensing, and the lack of latent heat in the room makes the indoor coil too small. A couple of suggestions 1) install a fan speed controller, and make sure the indoor fan seed is set to high and is not changed this will ensure the unit will have a long and happy life.

hendrag

Hi, Hendrag. That was brave of you to announce your post. You seem to have a tough job ahead of you, particularly with honouring the labour payments due in connection with your company's warranty promises.

Anyway, back to the wall-mounted LG unit in this Server Room: 5.2kW ASC186TLBO (410a), which had it's compressor replaced in Dec06 by the previous fridge company.……If this equipment is unsuitable for this Server Room application, is it worth this customer spending more good money trying to bodge things along, or would it just be better to swap it for equipment that will work in this application?

I appreciate that, either way, there needs to be some way of bringing some constant moist air into the Server Room (filtered), and that the Room Unit should be kept on high speed, but…………the question I would like answered is, if we were to fit a missing FSC (possibly the previous company fitted this when replacing the compressor in Dec06 - I have to get that checked) but, if we fitted the FSC, would this equipment then be happy in this application, and operate through the winter temperatures, and give about 10 years good service etc?

Many experienced engineers would say throw it now and install other equipment that can be relied on – what does LG Tech Support UK say?

[Suffolk Fridge]

or possibly a proper close control unit designed for server rooms, ie stultz? dx cooling with built in humidifier bottles. anyone installing splits in server rooms is askiing for trouble.

[hendrag]

A couple of points here to answer:

ref the sale of good act i couldnt agree more if a unit is not designed to work in a comms room and its operation data is widely published stating this fact then it should never be installed in this environment becauce it is not fit for this purpose.

ref the close control unit i couldnt agree more they should always be used for these applications but i think Liebert and stultz units may be a little more expensive than a simple split.

ref the will it last forever question the answer has to be if its installed correctly within the design limits it will run happily for years but lets just think about this for a second. A split system is designed to run in an office or domestic application, typically this means it will run for 10 hours a day for maybee 200 days a year total of 2000 hours a year or 20000 - 30000 hours over its life. This is the normal life expectancy for split systems. In a comms room if there is no lead lag or backup system 30000 hours will be reached much faster than this typically in about 4 to 5 years. With no back up i would be surprised if a single split running 24/7 would survive for 10 years no mater whose name was on the box.

so in summary if you install the head pressure control pcb the unit will march happily on and offer trouble free service. Hope this all helps

regards

Hendrag

[sinewave]

anyone installing splits in server rooms is askiing for trouble.



That's a rash statement Suffolk Fridge! :eek:

[l'robot]

If you look at the design charts, the LG unit is designed to operate down to an indoor of 20cdb/14cwb. Also the Condenser will only operate to an Outdoor temperature of 16c unless a fan speed controller is fitted.
The problem is that the fanspeed of the indoor unit will ramp down to a slower speed. In high sensible applications you want a high fan speed all the time. This will require modifying the wiring of the indoor fan motor. So that the fan is on high speed only.
The compressor fails due to number of starts (life expectancy) and /or liquid problems.

[absolute]

Agree with Vicking, Although I would be interested in knowing if there was a condencer fan speed controler fitted.

If not then at ambientrs below 17 deg the head pressure will be so low it will drag the suction pressure down and cause the evap to run below freeze point and cycle on anti freeze stat if your lucky, Most of the time the probe will not pick up the freeze befor the coil frosts up.

Humidifiers good too just costly to run and adds sensible load as well as latent.

[Sledge]

HI

I am not familiar with the LG

I am still thinking about Gary's suggestion, regarding the installation of a EPR.
I dont think I have ever seen that idea in a server room unit,

Would this work? I can see that installing and operating a humidifier to provide a latent load on the A/C seems like a waste in every direction...

but wouldnt you still need some humidification, even with an evap pressure maintained at some higher point. If it is cooling, it will still be doing some dehumidification.

I am surprised that there isnt excessive static electricity, with humidity that low.

[Makeit go Right]

I would be interested in knowing if there was a condenser fan speed controller fitted. If not, then at ambients below 17 deg the head pressure will be so low it will drag the suction pressure down and cause the evap to run below freeze point and cycle on anti-freeze stat, if your lucky. Most of the time the probe will not pick up the freeze before the coil frosts up.

Been a bit busy but here is the answer……….There was no FSC/Head Pressure Control fitted, so the thing never had a chance.



Ref, will it last forever: the answer has to be if its installed correctly within the design limits it will run happily for years. .... If you install the head pressure control pcb the unit will march happily on and offer trouble free service.

I am not so confident that this equipment will really march on happily through a couple more winters, even if we fit a FSC/Head pressure control. I have recommended replacement with something that is in better suited for this application. (No, not a CCU – we are not talking in those terms at all for such a small computer room, and for the company in question. So, skip all of that.)

Meanwhile, we can reposition this LG into a nearby office where it will have a better chance.

[Gary]

HI

I am not familiar with the LG

I am still thinking about Gary's suggestion, regarding the installation of a EPR.
I dont think I have ever seen that idea in a server room unit,

Would this work? I can see that installing and operating a humidifier to provide a latent load on the A/C seems like a waste in every direction...

but wouldnt you still need some humidification, even with an evap pressure maintained at some higher point. If it is cooling, it will still be doing some dehumidification.



This isn't necessarily so. For example, if the room air is 70F @ 50% RH, then the air temperature must drop to it's dewpoint (about 50F) before dehumidification starts. If the coil surface temperature is 51F or higher, there will be cooling without dehumidification. (Note: I'm not sure these numbers are entirely accurate as I don't have a psych chart handy... but I'm thinking they are somewhere in the ballpark)

[barnsie]

domestic refrigeration in a server room !!! must be a no no ! if the information stored is worthless and there are no critical services then maybe !

[paul_h]

Cheap domestic splits have no business in server rooms. They're not made to run 24/7 for starters, parts aren't readily available in case of breakdown.
I'm sick of all the IT people jumping up and down at us to get their broken wall split going that same day.

Put a local made ducted system in with humidty control. Using ducted means you don't even have to run the compressor constantly, you could use thermostatically controlled dampers to pump in outside air if the outside ambient is lower than rooms return air. Using a local made ducted or package also means you can get the parts for it straight away in the even of a breakdown.

[Simon Butler]

Paul, that is the ideal, if only I.T. companies thought a little more about cooling before they bought their buildings. So much energy could be saved by just pumping in filtered outside air, or using free cooling, there's plenty of cold available for free in this country! In my experience even if you could get them to part with the cash required for a decent system there just isn't the space available.

[AcidSlasher]

the drain from the indoor units could always be used to feed the humidifier, that way the moisture that comes out of the air would be fed back into it

[Simon Butler]

Couldn't the moisture be put back into the room using some sort of evaporative cooling rather than adding more heat to the room, or is this already an option with big downflow units?

[Refrigerologist]

Low humidity stopping equipment from cooling!
I know that Diakin experienced this problem with the old range of R407C inverter equipment. Since the introduction of the R410A sytems the problem has been alleviated. I know of many installations of wall mount splits or cassettes installed in server rooms and these operate with no problem all. In fact I have had, on two occassions, due to lack of floor space, and, above ceiling height, installed 3No. Daikin RZQ125s with cassettes operating server rooms with a sensible load of 16kw. The three units operate via an auto change over/alarm panel, with the third unit being a standby. But you all know what the clients' are like, Oh look! we have some spare capacity, so lets load the room to the hilt! I now have rooms where all three are having to operate, but these still work with no problem at all. I have also done the same with Daikins' wall mounted kit with no problem at all.

However, I always advise my customers. that the best option is a 'proper' down flow full function unit. Ultimately we live in the real world and it all comes down to bean counters and their budgets!

[brunstar]

yes well what can i say i have put in a whole lot of LG units and they really run by their name, Lucky to be Going.
I am not a fan of their equipment unless it is a high ambient application.
if you have to take 66 screws out of it to get the cover off, there is something to hide!
I have had nothing but bad experiences with them in regards to service..
people have their own preferences and they are not one of mine unless i want to buy a cheap product for a nieve client and charge them a mint, but you do get what you pay for..
sorry to upset anyone..

[praveen]

:confused::D

dehum & humid requirement raised in data center when external air enter inside the server room.

Sealed the room & make it air tight.

Regards
Praveen

[brunstar]

Sounds to me like all three units are suffering from insufficient load/low coil temp/excess dehumidification, possibly as a result of insufficient airflow.

I'm not sure that adding latent load is the best solution. This has the humidifier and dehumidifier (function of the A/C) working against each other.

If the airflow cannot be increased to raise the coil temp, possibly EPR's would do the trick.
Gary, well raising the humidity will do the trick as it will allow for the refrigerant to boil off, if you have more air over the coil it will ice up too as it will evaporate too quick.
the only way to to it is to set the unit to low humitdity mode and depending on how low it is add more humidity..

[Gary]

More airflow over the coil makes it less likely to ice up, not more likely.

[back2space]

Gary, well raising the humidity will do the trick as it will allow for the refrigerant to boil off, if you have more air over the coil it will ice up too as it will evaporate too quick.
the only way to to it is to set the unit to low humitdity mode and depending on how low it is add more humidity..


What is low humidity mode? HIgh fan speed?

[Suffolk Fridge]

Old thread now i know, but i have just seen some very smart kit. "ultrasonic humidifiers" A roomfull of splits struggling in a server room at 20%RH became units all reaching setpoint happily with the addition of the aforementioned.
These pieces of kit are stainless steel, wall mounted units with a 15mm water connection and an inbuilt humidstat.
The water fills up, and sits on a plate. The plate then vibrates/agitates extremely fast (i.e ultrasonic speeds) which creates a fine mist of water vapour, at room temp. Not 100C as with a conventional humidifier cylinder.
Visit a company called Carr Marketing for more info.
By the way, we are currently doing a server room out with 3 denco close control upflow units, still by far and away the best solutions in this application.

[adeelquick]

First Of all LG wall mount Split Type DX Air conditioner are not recommended for an I.T Room. This unit cannot provide an operation of 24x7 and cannot provide the actual sensible cooling load + it cannot humidify/reheat.

[Makeit go Right]

"ultrasonic humidifiers" A roomfull of splits struggling in a server room at 20%RH became units all reaching setpoint happily with the addition of the aforementioned, with a 15mm water connection and an inbuilt humidstat.

At £1500-odd a throw, plus power supply, water supply, and filtration of water supply, you might be better starting in with a proper CCU.



By the way, we are currently doing a server room out with 3 denco close control upflow units, still by far and away the best solutions in this application.