I am wondering if any of you can tell me how well this system works and if theres anyone who has installed them, how hard or easy are they to install. thanks
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I am wondering if any of you can tell me how well this system works and if theres anyone who has installed them, how hard or easy are they to install. thanks
The first one is hard to install because they have so many kits that you have to order. Then when you get on the job you realize they are the wrong kits. But after you educate yourself with the product you don't make the same mistakes when ordering.
They are expensive as compared to a conventional system. But we have not had any service related problems. Also they are a little noisier. (air noise)
If you are going to get into unico you will slowly get a build up of leftover stuff that you can get yourself out of a situation of not enough parts.
[Edited by benncool on 12-15-2004 at 12:29 PM]
Or should you say, does it NOT work.............We have put in quite a few of these systems and every single one has freeze up problems.Quote:
Originally posted by heatingforu
I am wondering if any of you can tell me how well this system works
A perfect example: we did a church job back in 1999, and UNICO deigned our system. We gave them all the load calcs, and they told us how to install the system. It is 2 5 ton staged air handlers with 2 5 ton condensers. Main trunk is a loop, with 71 supplis running off of it. I went there in 2002 cause of a compressor burnout. Put in the new compressor, fired it up, suction would not come above 40. Checked the 2nd stage condenser. Yep. Same thing. Called unico and explained everything to them and they said it needed more supplies, this, that and everything else. I said "YOU PEOPLE designed this system, why all of a sudden is it now not up to your spec? they never did have a response. we added 4 additional supplies (Which got us to the 71) and still no go. Finally for the heck of it, I disconnected the duct from both AHU's and let them blow wild. Suction shot right up. Put it back together, sure enough, freezing up again. Never went back to that one, it is probably still not working right.
But every other unico we have installed also has freeze ups every single year.
Can you say foil tape? You better buy 300 rolls of it if you are even going to THINK about installing one system. EVERY single friggin' joint of pipe, including all elbow joints and every supply tap, have to be taped up.
Look at where the blower motor is in the air handler and see how the blower motor drives the blower wheel which is located in another compartment. Hope I never have to change one, cause it's gonna be a bitch.
Quote:
Originally posted by ct_hvac_tech
Can you say foil tape? You better buy 300 rolls of it if you are even going to THINK about installing one system. EVERY single friggin' joint of pipe, including all elbow joints and every supply tap, have to be taped up.
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I do this on every system I install...supply and return.
Seal all seams. Everytime.
Benny if noise is an issue you need to have more ducts per ton. The old rule was 5-duct per ton would produce 40 CFM per duct. That will produce noise if you go to 7-ducts per ton will put you at 28 CFM per duct and drop noise level to below NC25 silent 10-ducts per ton will be 20 CFM per duct and not even readable with a decimeter. At 40 CFM per duct you are moving air at more than 2000 FPM at 20 CFM it is 1000 FPM.
CT if you are having freeze up problems you need to adjust the CFM's of the motor that is done with an adjustment plate and amp draw. It really is not a problem and is really easy to do if ductwork is not properly designed and installed they will not work. Is your company and are you trained and certified by UNICO if not you need to be.
The need for tape or mastic is one of the keys to the systems. Most conventional systems have total duct leakage of as much as 35% and average 15% that is allot of wasted capacity and efficiency. SDHV systems are designed to have less than 8% and should be less than 1%.
If you install a conventional HVAC system you should also seal every joint and connection otherwise you are doing poor quality work and cheating your customers. We seal every joint with tape and mastic regardless of system type. Sealing all joints is also now part of the International Energy Code, which has been adopted by many, if not most states and or municipalities.
"The first one is hard to install because they have so many kits that you have to order. Then when you get on the job you realize they are the wrong kits. But after you educate yourself with the product you don't make the same mistakes when ordering." ....Benncool...
LMAO...very true although first one I did was spacepak this summer.
Unico has instalation videos, promotional material etc that they will send you if you are a contractor. The extra humidity removal they provide is great if you are in ahumid area. I would not use them for new construction but only for installs in older homes with no space for ducts because as mentioned they are pricey. Check unico's warranty if it is like spacpak it is only one year most conventional systems have 5yr all parts warranty. Also spacpak uses a metal drainpan which in this day and age is so dinosaur so that will eventually rust out as opposed to plastic check with Unico on theirs or maybe somebody here knows?
As for the freezing up mentioned I have only done 2 of these high velocity systems so I am by no means the last word on this but Spacepak has a sensor if ice builds on the coil it shuts down the condensor and I would asSume Unico does too. Icing will occur more frequently in these units if the duct work is improper they reccommend as was said a minimum of 5 drops per ton I did 6 per ton for the both I did. I would tend to believe it was occurring more from installer inexperience/error than a design flaw because I did not have that problem with the two I installed as was already stated by someone else.
UHHH Sealing duct joints....the fact that someone is complaining about it like they normally on a regular system would not have to be sealed......Well that just scares me but again each installer provides his own unique brand of quality.
Thehumid1,
There is a new deal on the warranty. If you go through their CURRENT certification class, and are a registered contractor with Unico, you will get a 5 year warranty on all systems. This is new as of about this summer. If you do not have the certification, then it is only 1 year. As Classical said, the certification is a good class.
Ct-- 71 supplies ??? on a 2.5 ton system. How long were those runs? were you even able to get 6" spacing ?!?
There are quite a few UnicoSystems going in new construction now in High end homes. People are using radiant floor and Unico, because you never see or hear the system.
It's all about comfort and you get a more even comfort with Unico
No it is a 10 ton system............2 5 tonners with staged condensers.Quote:
Originally posted by hvacprodmgr
Thehumid1,
Ct-- 71 supplies ??? on a 2.5 ton system. How long were those runs? were you even able to get 6" spacing ?!?
It's all about comfort and you get a more even comfort with Unico
Ct.
Sorry, I must have been speed reading!
Missed that part. Seen it when I read the second time.
Ct you say the condensers are staged are the blowers also staged. I talked to one of the Unico Engineers today and he it sounds as if the system is improperly set up and it is an airflow issue. If you are having freeze up problems on all your systems there is a basic flaw in your installation and setup procedures.
Classical when I say noise I mean more noise than a conventional system. It was my ear that could hear the difference it wasn't something the customer complained about.
We were told to use 6 ducts per ton. We have a Glass Master machine so we make all of our main supplies out or 9X9 duct instead of using the 9 round. This, I think helps.
[Edited by benncool on 12-16-2004 at 08:41 PM]
Benny they have ammended their recommendations to 7 ducts per ton. They started at 5 and have changed to 7 you can even go up to ten per ton.
They are perfect for the Houston climate but are very pricey for our market. We have one of the lowest dollar per sq.ft. values for homes in the country. We also don't have many older homes without A/C which is the original application for the system.
Around here if the home was built before the mid 60's and is single story it is usually torn down and some monster zero property line house built on the lot. They tear down a 1600 sq.ft. Bungalow and build a 3000 sq.ft. plus home and put in a $10,000 HVAC piece of crap system. Even the homes in the Million dollars plus range are using system that are hacked in for $800.00 to $1,200.00 per ton.
I want to do a large 10,000 sq.ft. home with a Unichiller system so bad but hard to find someone to foot the bill.