01-21-2005, 06:19 PM
I'm not looking for it to work by accident...I don't even want a "Predictable Suprise", by this I mean one or two anticipated problems a year. I want a system that works and I don't have to worry about it, just maintain it, give it checkups, and I'm very happy and content...I will get the money for it...but only after bad days have fallen, that's the way it is in the business world sometimes.
I'm fine with 70....I will see if the Liebert guy can fit me with a backup system to keep on the backburner....in the summer, the unit may not be able to run at 70 or even 72, and that will be when I really have a fit and demand to put in the proper system....by that point I may even be willing to pay for some of it out of my own pocket to prove the point (and then pray to be reimbursed, but if I don't it's the price I pay for sleeping soundly at night)
Chillerdude....the unit froze up once on Christmas morning....it was set at 68 or 65, I don't remember exactly, the fan was set to auto, and the supply duct grill that was closest to the return was facing the return, since then, the grill was rotated to face the back of the room away from the return, the fan is at the on position, and the tstat is at 70. I don't like when my room goes thermal on me, and it will happen faster than my 3.5 lt V6 can get me to the office, so I don't want to test it by setting it to 65 and monitoring it all night and all day.
My installer says I can set it to 65 and forget it now, I think he feels the freeze up happened b/c the fan was on auto and not set to "on".
Bottom line is that I don't trust this unit to work under 70 so I'm not going to bother....in the summer I will see if it can handle it, and if it can't I will install a liebert as I stated above.
[Edited by serverroomcooling on 01-21-2005 at 05:21 PM]
01-21-2005, 06:26 PM
What about dry bulb temperatures....does he at least have a simplet thermostat to take temperature readings?????
John J. Dalton
PS: Is he still there????
01-21-2005, 06:36 PM
he's gone...says he doesn't have what he needs for that, not even in the shop....
01-21-2005, 06:47 PM
Please describe to me what the instrument looked like that he was reading CFM from…….the one that read 500, but he said that meant 400 CFM??????
John J. Dalton
01-21-2005, 06:54 PM
it ha a big chute that the air went into...I guess some resistance fans on the bottom....a dial with different numbers on it....the needle went from all the way to the left to a the way to the right.....he said it means it's actually 400 cfm....and al 3 had the same readings
that's all I know
have a great weekend, I'll be away....not thinking about this for a few days
I'll catch up sunday night
01-21-2005, 06:55 PM
you need a flow hood to measure cfm properly.
FILL OUT YOUR PROFILE!!
01-21-2005, 07:03 PM
flow hood sounds like a good description of what he had,,,,it was pretty big and he placed it right underneath the vent, all the air from the vent went directy into it
01-21-2005, 07:06 PM
I agree with you, at this point I would settle for a static pressure measurement. At least we could use the ESP data for that A/H and determine if the unit is putting out the correct cfms and verify that the unit is properly sized, duct wise.
I really thought that this contractor was ok, since the only evidence that I have read to the contrary was that it froze up once and that it didn't appear that he did a load calculation. BUT now we says he doesn't have a tool to measure the wet bulb??? I may give some tech the benefit of the doubt if he has his psychrometer getting re-calibrated in January if he were in Syracuse, but this guy is in South Florida (Don't leave home without it) And to make matters worse, this guy is not installing small residential cookie cutter stuff, but very specialized applications.
01-21-2005, 07:11 PM
A flow hood huh, Well that would be the right instrument. I am impressed, I do not have one of those in my truck at all times, I have to go to the shop. Though I haven't seen the flow hood that reads all the way to 500 but means 400. My balometer doesn't give me such a neat round picture of supply cfms. Boy he sure sized the duct perfectly to get exactly 400 from each supply run, or did he???
01-21-2005, 07:37 PM
Hey John, it was 1 unit for each server room.I think the rooms were maybe 12x8 ft, I took what the salesman sold the customer and installed it, didn't think anything about it to tell you the truth and actually it is only the 2nd and 3rd splits I have ever installed in my life as I usually only work on chillers.They have run fine for over a year now so we must have guessed right.
01-21-2005, 09:05 PM
Is that the fat lady singing?
Please view the following:
Day before yesterday at 1:56 PM:
Thehumid1, I know you and I don’t see eye to eye regarding the abilities of the original HVAC contractor, but I just have to tell you, I’m a little bit skeptical of these readings being obtained from this company. With that said, I’ll hold my tongue regarding any other reservations till the readings are posted. Sure hope they all come in, but time will tell.
Day before yesterday at 4:37 PM:
“Guys…..I hope I’m wrong…..boy do I hope I’m really wrong…but, I have to tell you I just have this funny feeling that these readings we are all waiting for ……are going to be disappointing to say the least. Again, I sure hope I’m way off base here, but…….”
Yesterday’s post at 1:20 PM:
“Lastly Tom, I like you am highly, and I mean very highly, skeptical of the accuratency of the readings we are going to be given, but like everyone else here on this thread, I reserve final judgment till the readings are in.”
The fat lady is singing and I just have to tell you………..whoever took these readings….I’m being careful here………should be ashamed of themselves.
John J. Dalton
01-21-2005, 09:41 PM
You posted before on this thread that I should not “judge” the original HVAC installation contractor solely on what Serverroomcooling was telling us. At that point, I stood corrected, and said I would reserve my “judgment” for another day………Do you think that day has come my friend?
Please let me know as quickly as possible since I’ve gone out on a limb and said the service technician, (again, for lack of a better term) that came out to give us our readings, should be ashamed of himself for the information he provided. Was I too harsh with my criticism of him? Should I apologize for this statement?
What do you think my old friend?
John J. Dalton
01-21-2005, 11:36 PM
Re: One last one and I'm outta here
Originally posted by twcpipes
Serverroom, please exclude yourself from this thread and may I say good luck with your project.
1. John, no worries I really wasn't upset. It's cool. Maybe we can hook up sometime. Besides I can't add any more to this thread anyway as it has become somewhat of a fiasco between certain people wanting to get in each others faces with knowledge they don't have. Go figure why jobs don't work 70% of the time.
I still contend it has something to do with the new millenium and "No Children Left Behind". :>/
2. And to you Humid1: (even though I don't know why)
I will endeavor to help you once again. You and your homes cannot be even compared with the commercial arena of server rooms. First off your houses don't necessarily have to operate 24/7 like a server room or any other room requiring exacting temperature and/or RH. Also you need to look at outdoor ambients from a 70 degree viewpoint, not 60-65 for head pressure control. You say you would use hot gas bypass instead of condenser fan control but you have to learn for hot gas and colder ambients you still need head pressure control. That is if you want to do it correctly. Refer to Sporlan technical data for that issue as you really need to learn more in this area for expertise.
The last item would be that until Boss (I'm grateful for him having this website) tells me I don't have as much right to be here as you, I will continue to pass on knowledge to anyone I can help. After all the years I have spent in this Industry and always applying myself to gain knowledge, I don't need your arrogant comments coming my way. You may wish to stay with your little energy-star houses and the residential section of this website. Your choice, of course. I was attempting to pass on some information to help you and others with commercial work in this project vane as I considered this thread to be a commercial section. I normally don't feel I have to explain myself but in this instance, again it may help others.
All take good care in this thing and have a super day.
me, "the pipes"
"You say you would use hot gas bypass instead of condenser fan control but you have to learn for hot gas and colder ambients you still need head pressure control."
That statement is absolutely untrue and if you check sporlan data a)you will find they reccommend it over head pressure control not in conjunction with....
I posted this on page 4 it is directly from Sporlan:
Turning off a condenser fan stops airflow through the condenser, but the condenser is still left as a fully effective heat exchanger. If a wind blows through the condenser, it can be as effective a condenser as if the fan was running. Fan cycling also causes sudden large changes in head pressure that has an adverse effect on the TXV. Fan cycling is the most common method of head pressure control because it is the cheapest method. The best low ambient head pressure control method is to flood the condenser with liquid refrigerant. This is the only method that effectively makes the condenser inactive.
So Sporlan says the head pressure control is rendered totally useless in days of high winds and ...much like the Santa Anna winds you get there .... and has adverse effect on the TXV....they say it is the cheapest method...
FUNNY how you consider every doomsday situation like humidity in LA but not this I believe your comment was "It is not always windy out..."
You feel the need to address these issues but not the wind scenario which would render your P66 and head pressure control useless:
And throughout this thread I have been saying the whole thing was being overengineered the contractors sizing was correct and it would work....
And all these pages and pages and you know what
without commissioning/readings....yet the system is adequately providing the needs of the serverroom...
with no head preesure control or a valve....
So explain that... even in 45 degrees it held the required temp....
Despite everything and all MOnday morning quarterbacks myself included the system is serving the needs of the customer.
Job done successfully ... end of story.... because its hard to argue with success...
And guys in here have posted they merely used minisplits and they worked well ....So how do u explain that in contrast to your theory of sizing and installing systems to handle every extreme weather condition???
Or are you saying those that posted that are liars?
So continue to make your mountains and go into analysis paralysis ... while your doing that the techs will be taking care of these molehills and moving to the next job so they can feed their family.
thehumid1-------I live in NJ, a state where it's free to come in but you have to pay to leave!