I think contacting an enginner for a server room unit is a waste of time.Put a 5 ton Sanyo split in there and call it good.Why pay an engineer when any good reputable shop could do the same thing, not MA&PA HVAC but a large commercial shop.
I am here to gather information.....Engineers and HVAC people come in here and charge an absolute fortune. I don't know who to trust. I am gathering information and will make my judgement afterward.
BBCMG04, great post....I have all that information, just never knew really how to use it properly. I have 52 AMPs running to a UPS and everything is plugged into it. I believe the line is 208 volts, which should be 10816 of average watts, am I right?? which means I would need roughly 37,000 btu to cool it (3.413 btu per watt, which is a 3 ton unit. That would hold me over for now.
the room is roughly 100 sqaure feet
I will be adding equipment so I am looking at either a 3.5 ton unit or a 5 ton unit.
I brought in another HVAC guy who want to sell me a Goodman unit and says a 3.5 ton unit will make the room a refrigerator and be fine no matter how dense I get in the racks. I told him we would potentially have 4 full rack. He said all will be fine and cool. He also said that 5 tons won't be much better than 3.5 b/c the room is so small. (he also is charging half of what the other guys were charing for a 3.5 ton unit)
The difference in the equipment is that the cheaper guys say I don't need a 2 speed system and that if one compressor goes, the other dies as well (it's a Carrier condensing unit M#38TDB060---3 and a Carrier air handler unit M#ANF006000)
the guy who wants to put in the Goodman unit wants to put the handler inside the server room instead of in the drop ceiling, and says is does not matter where I put in in the room since it's so small. I figured it would be best to have the handler near the back of the servers so it sucks in the hot air
I really need to know if this second guy is correct or not. He is telling me that the other HVAC guys are very over priced and was appauled at what they were saying I need.
what do you guys think??
bbcmg04, I don't see your email, so I'll reply again here in the forum.
I love your post, it's great!!
so it seems the guy who wants to put in the small unit is correct, and I'm going to figure out what my needs are right now....here's my next question....if I need a 3 ton unit right now, and put in a 3.5 ton unit right now, will that endanger my equipment?? A 5 ton will defenitly do that.
right now, I have 2 1 ton spot coolers blowing directly on the servers and things seem to be working ok like that. The room is hot, but the server cases and the air coming out of the back of the servers is not hot. which I'm happy about. Does this mean that 3 tons is overkill, and that 3.5 would be really overkill?
I can forsee another 2000 watts of computers (factoring in the 50-70% of total watts) coming into the server room over the next 6 months or so, which would require another .5 ton anyway
I think I am finally begining to get clear on this issue.
My guess is that the best place to put the air handler is close to where the air leaves the servers. I know in larger data canters they have what is called hot air aisles which are empty compartments where all the hot air gets ducted to before it gets sucked out of the data center.
I plan on having 3 ducts in the ceilng in front of my servers so the air flows down and sucked into the servers. I figure if the handler was behind the servers it would suck out the hot air and keep the room cooler....my latest hvac gus say it won't make much of a difference where the handler is, not sure if he's right on that or not
I think this would be my best config...Duct and vents being in the ceiling
Cold Duct Return Vent
If humidity isn't critical and the room is small I would suggest going with ductless splits. If the room is as small as you describe, you don't want an air handler taking up floor space. You also don't want an air handler in a ceiling where if condensate problems occur, it could damage equipment. Cooling from the ceiling when the computers are at or near the floor is OK to cool the room but your not doing a lot for the computers. As was said before, you have to move the cool air across the computers. Ductless splits with air sweep would be better. With your current load requirements and future load I'd suggest two 2.5 ton splits for redundancy. The most reliable are Mitsubishi's and Sanyo's but they carry a hefty price tag. Fujitsu makes a good unit at a fair price. When selecting a contractor for this type of application ask for references and call them. Go with the contractor that you feel comfortable with that has good references and not the cheapest guy! Do not put goodman equipment in a computer room! An engineer shouldn't be needed on this type of installation. I'd equate it with hiring an architect to design a doghouse. Use that money to pay the quality contractor.
Your server room
Can you answer three questions first?
1. What does it cost you, or your company, to be down due to high temperature in the room?
2. Is there a maximum temperature derived at that shuts any critical equipment down?
2. Have you, or your company, established a budget for this project?
cost for downtime is hard to equate, there are so many variables. We are in Healthcare, so we don't have eCommerce but we run everything throught the servers in the server room for every location so when things go down people don't trust the systems and it takes time to gain trust again. I don't ever want to be "down" In three years, I can remember only about 5 hours of downtime, 3 hours being when the 1.5 ton unit I have in the server room died within a week of moving in. I don't ever want to be down!!
Maximum temp would probably be in the mid 90s, that would be when the servers get too hot to run. I would like the room to be 70 at the very highest
my budget is between 3 and 8 thousand.
Every server room professional I have brought in has wanted to charge 20,000. Regular AC guys say that all I need is cold air in there, 3 tons is plenty and it should be about 5,000....
The guys I trust the most want to put in a 3.5 ton, two speed Carrier system (with the handler in the ceiling, but not over the servers, in the ceiling in the room next door). People have told me that a two speed system is useless becuase if one compressor dies, the other does not work redundantly and is useless, but I don't know if that is really true.
I will try to get the guy who wants to put in a Goodman system in, to put in a better system, he swears by Goodman, but he said if I want a different system he could put it in for me
Every server room professional I have brought in has wanted to charge 20,000. Regular
Its a gamble!!!!
How much does the room cost you when it goes down????
What type of emergency plan do you have in place when room does go down.(does it justfy redundency or at minimum a spot cooler in store room and dedicated outlet to plug in spot cooler?)
I would at minimum put in a sensaphone (very economical) so that you will know if the room goes down at night if no one is present...
In your market you usually get what you pay for.
don't spend millions on computers and pennies on air conditioning
I don't ever want to be down!!
Your budget is extremely short if you "never want to be down".
I don't know if your budget is for a complete installation but there is also electrical service to be done as I am sure you have found out as well as the outdoor equipment location set up. In other words roof work for platform and sealing or at ground level for outdoor type unit(s).
What have the three contractors proposed for equipment referring to split system or package or?
Also, to "never be down" you might want to consider redundancy with two systems or at least an exhaust to pull the heat out when, or if, the a/c fails. I am surmising you have surrounding areas of conditioned space.
I have backup plans to cool the room in the case of a failure, I will be notified via pager if the temp rises above the set threshold.
My budget is not set by my department. I would love to spend 20,000 as that would give me the leverage to put in redundant systems that will help me avoid executing my disaster plans....but I need to work withing my means for now.
two splits given you are going that way wouldn't be worth $20,000 especially if both were installed at the same time.
anyway, good luck to you
If anyone is in the South Florida area and would like to come by and quote me a reliable system, please let me know
I have decided on buying a 3.5 Ton 12.25 seer Trane unit with an A frame handler on the server room floor. I will be placing 3 ducts in the ceiling in front of my server racks, and one in the back corner (which actually comes to a point, the room is like a rectangle, but as you walk to the back, the room ends up in a triangle). The duct will be back there providing cool air for my switches, and the handler should pull that air back around the other side of the servers where the heat is and possible cool that area too. The handler will be on a stand and will suck air from the bottom for maximum airflow (or at least that's what I've been told when stressing that I need max airflow)
If 3.5 tons is too much, I will move a duct either just into the ceiling or use it to cool another room.
I'll let you guys know how it goes....thanks for all the help, and let me know what you think of this configuration
Sounds pretty much the way the gut selling Goodman quoted except it is a Trane.
thehumid1-------I live in NJ, a state where it's free to come in but you have to pay to leave!