Air conditioning advice

Hello to everybody. I'm looking for an advice regarding air conditioning a 20 square meters control / tracking room. The room is already built so we'll have to make the air conditioning fit in what's already there. At the moment there's no air conditioning nor a ventilation system. Heating is not really required. Since it's also a tracking room I'd need a very silent machine. I had been looking at some new split Mitsubishi model (MS-A09WA) but, besides the price (about 3.000 cdn), it has no ventilation like all split (non ducted) systems. Any advice ? Thank you

I can't give specific help (like model numbers and such) but there has been a discussion here recently (try Kathy's Studio Build Diary) that stated that in fact there ARE split systems that DO provide ventalation too. I think her thread even had a web link from Rod Gervais (our resident expert) that listed just that kind of A/C unit. len

Well. Len, thank you ! It took me two hours to go through that endless but extremely interesting thread. At some point they got to talk about Friedrich Room conditioners but as far as I can see they haven't come to any conclusion yet, so now what I'll do is to check with a local Friedrich representative/distributor to see if they actually are one of the few (or the only?...) ductless conditioning system with ventilation capability. One negative thing is that they do not give any sound ratings for their conditioners, because according to them "There are no sound level ratings established under AHAM (Association of Home Appliance Manufacturers). There are many variables that affect the level of the sound coming from your unit which can not be tested by appliance manufacturers. Some examples are: type of installation (thru-the-wall vs in a window) and type of building construction (wood vs brick.) " Further opinions appreciated.

That wording sounds like a cop-out to me. Of course there are ways to measure the noise. I think what they are getting at though is that the amount of noise the outside unit makes COULD be significant if you only had a hole in the wall and a 4" tube connecting them together. They could tell you how much noise the inside makes all by itself so at least you'd have something to measure by. I will have to leave additional comments to others since I have a "regular" A/C system. len

Did you get to the "cautionary tale" about running electrical conduit instead of water pipe? :) I had to feel sorry for her on that one... That thread is a really good read though. She's documented her construction really well.

I think she has become everyone here's hero.... :P :P :P

I've investigated a little more about Friedrich conditioners. It seems the only ones that provide air ventilation are the window or wall mounted, I mean, not the split systems. :roll: :evil:

Not sure this will help you, but check this thread out. http://johnlsayers.com/phpBB2/viewtopic ... highlight=

Thank you Stan for this very useful link. Unfortunately I don't think this is exactly what I'm looking for, as far as I understand this is about ERV units that can be added to an AC system. What I'd need is an 'all in one' conditioning/ventilation split (ultralownoise...) system... but I'm starting to think it doesn't exist... :roll:

Ok there's an update regarding Friedrich conditioners. I got an email from them saying : 'The Quietmaster and the Twin Temp units are not split systems. They are window units which can also be installed through a wall depending upon the thickness of the wall. Both of these units do have a Fresh Air/Exhaust function. When on Fresh Air, the unit will bring in approximately 5% of the listed CFM for that unit. When on exhaust it is approximatley 10% of the listed CFM. On the split systems, the Floor/Ceiling Universal Heat/Cool, the Ceiling Cassette Heat/Cool and the Ceiling Suspended Heat/Cool units all have fresh air capability.' Which leads to some considerations: - can this function be considered as a proper ventilation system ? - the three models they indicate are respectively (approx) 22.000, 34.000 and 22.000 btu, way too large for my room (20 mq)... - I found some noise rating data. For example, the Friedrich C24YE (MC24Y3E Indoor/MR24Y3E1 Outdoor) DUCTLESS SPLIT-TYPE SYSTEM CEILING CASSETTE 23,500 BTU, which costs about 2,900 US $, is noise rated (indoor unit) 39-42-44 db, which is WAAAAYY higher then the one I chose in the first place, Mitsubishi Electric MS-A09WA (26-32-40 db), but it was a 9,500 BTU Cooling only with no fresh air capability. A more comparable Mitsubishi Electric Model (MSZ-A24NA, Cooling and heating, 22.000 BTU) is rated 34-40-49 db. The Friedrich S36CE (MS36C3E Indoor/MR36C3EOutdoor) DUCTLESS SPLIT-TYPE SYSTEM 36,500 BTU rates from 45 db minimum (45-49-51)... - the thing is, I don't need this 22,000+ BTU, and I don't want a constant 39db noise in this room... :cry:, but I need some oxygen !!! :shock: Keep on investigating... :(

Welcome Steve. 8) I feel your pain. I went through it as well, trying to find an all in one ventilation system and air conditioning system for my rehearsal space. I finally settled on developing a solution that uses two separate systems to accomplish the separate goals... One for cooling, one for ventilation. I would encourage you to do the same. Here is the point in my project thread where I conclude that I'd be best approaching both challenges with separate systems. --Keith :mrgreen:

I have (what can hopefully be considered as) good news from Italy... a specialized website told me there's a small number of monosplit inverter air conditioners that also take care of ventilation: - Daikin FTXR28E/RXR28E (9,500 btu) - Daikin FTXR42E/RXR42E (14,300 btu) - Hitachi RAS25JX4/RAC25JX4 (8,500 btu) - Hitachi RAS35JX4/RAC35JX4 (11,900 btu) In particular the Daikin models, also known as 'Ururu/Sarara' also take control of humidity. Has anyone heard anything about them ? I have to investigate if they are distributed and sold in US/Canada. To be continued... :arrow:

Well, the Daikn says 'we do not sell the Ururu Sarara in North America and we do not have plans as well, sorry.'... :arrow:

Hi Steve, I am reading every word you write with lots of interest as I am still without the heating/cooling/fresh air system I need. I am still committed to getting a mini-split system that offers all 3 functions. Like you, I only need a 9,000 or 12,000 system. Anything larger is overkill and too much money. Since I have had my hands full with other aspects of constructing the barn I have not revisited this issue in a while. Now that spring is here I need to focus on it as well. Please let me know of anything you find and I will promise to do the same. There MUST be a small unit out there that does what we need. I can't imagine using any other system for my studio now since I've made no preparations for ducting or other requirements. The mini-split is the way to go if we can just find the right one! P.S. Thanks for reading my thread by the way. As you can see, I've made big mistakes - some that were caught just in time because of this forum and some that were not (ie. the wiring thru water pipes instead of electrical. I was too far in to really make the changes so I made do with my complicated layout and the hundreds of feet of PVC I invested in. But the compromise is that I will NEVER be able to run any new wire thru those at a future date for sure! :oops: :roll: But that's ok.......

Kathy wrote:

Please let me know of anything you find and I will promise to do the same. There MUST be a small unit out there that does what we need. I can't imagine using any other system for my studio now since I've made no preparations for ducting or other requirements. The mini-split is the way to go if we can just find the right one!

Don't hold your breath (no pun intended). I spent countless hours looking for such a "magic" system and I was never able to find one, so I settled on developing a solution that uses two separate systems to accomplish two separate goals (one for cooling, one for ventilation). If you find such a magic system -- offering the "one small hole" benefit of a mini split, while simultneously offering a very high rate of ventilation air exchange -- I'll probably buy it... But I just can't see how that can be done. Take a good long look at my solution, because you'll probably need to do something like it. Repeat after me: "four big beefy silencers." --Keith :mrgreen:

sharward wrote:

Don't hold your breath (no pun intended). I spent countless hours looking for such a "magic" system and I was never able to find one, so I settled on developing a solution that uses two separate systems to accomplish two separate goals (one for cooling, one for ventilation). If you find such a magic system -- offering the "one small hole" benefit of a mini split, while simultneously offering a very high rate of ventilation air exchange -- I'll probably buy it... But I just can't see how that can be done.

Well, I've heard more than once now that these systems exist. Rod even said that some mini splits have fresh air. How MUCH fresh air is the question you probably have - you have a number for code in mind. You probably have a larger room than me, too. In my case, I only need SOME fresh air. Mostly because, since scrapping the idea of creating both a tracking room and control room, things have changed. My one large room has a door directly to the outside driveway (with glass no less....ughh for sound.... but beautiful for views!). I am indeed adding a second interior door with an air lock there BUT the reality is that I won't be recording live acts very much and actually look forward to having my driveway door wide open most of the year for the sun and breeze. I've positioned the drum riser and a bench for playing guitar and bass so that they look out towards the driveway should the door be open. In my case, no matter what my local code will dictate (I need to look it up), I already have a "source" of fresh air. But still, we know that the door (and the second door with the air lock) will be closed a lot. So, I'll need fresh air. I also need heat along with the air conditioning. Winters are cold here in New Hampshire. I have heard that there are units to do all 3 features and I trust that even more knowing Rod confirmed it. FINDING them seems to be the hardest part. You're crushing my dreams but I'm hoping to be able to prove you wrong. If not, well.......I guess I best find time to get over to your thread and read about your solutions and personal journey in this subject. I shall keep my fingers crossed just the same!!!!

Kathy wrote:

You probably have a larger room than me, too.

:lol: :lol: :lol: I WISH!! :lol: :lol: :lol: I'll be lucky to have 120 square feet in my tiny little room when I'm done. :roll: Remember -- you need enough air to replace a window.

indeed adding a second interior door with an air lock there . . .

. . . And, as such, you need mechanical ventilation. Period.

BUT the reality is that I won't be recording live acts very much and actually look forward to having my driveway door wide open most of the year for the sun and breeze.

I'm almost certain that argument will not get you anywhere with your building department. :roll: I tried to play the "I'll open up both my doors and run a fan to exchange the air now and then" card, but the senior inspector at the counter of the building department shook his head the entire time I was saying that. :shock: I felt this big. :(

But still, we know that the door (and the second door with the air lock) will be closed a lot. So, I'll need fresh air.

Yes, in the form of mechanical ventilation.

I also need heat along with the air conditioning. Winters are cold here in New Hampshire. I have heard that there are units to do all 3 features and I trust that even more knowing Rod confirmed it. FINDING them seems to be the hardest part.

From what I was able to see, there are companies that make mini splits, and those same companies make compact systems that also do partial fresh air ventilation -- but I have yet to see one model that does it all. Remember, I'm factoring in true "mini split" design. You seem very motivated to find such a system. Again, if you find it, I'll probably buy it if it will meet my needs too. I am, however, betting against it. This dilemma caused me more delays and headaches in my planning stage than I care to recall. I couldn't get my building permit without solving the issue... I'm surprised you were able to get yours. Did you get yours already??

You're crushing my dreams but I'm hoping to be able to prove you wrong. If not, well.......I guess I best find time to get over to your thread and read about your solutions and personal journey in this subject.

I'm sorry you feel that I'm "crushing your dreams" -- in reality I'm trying to get you to solve this bridge-crossing issue before you come to it (and you're much closer to it than you think -- really, this is something you should have worked out before you put your first hammer to nail). You're going to have to design the system and plan the construction around it, especially if you do what I am going to do with the "big beefy silencers," not to mention the electrical. I posted a direct link into the specific part of my thread where I solve my ventilation problem -- bypassing all the turmoil I went through getting there. It won't take long for you to zip in and see my solution. It does go through a few iterations, but overall the concept is the same throughout. If you're really curious you can go back a couple of pages and experience my pain, including the part where I consulted with my local building department. You've come a very long way in your project -- impressively so -- but it seems you're just "faithfully hoping" this problem will solve itself or that you'll solve it when you get to it. Well, you need to get to it, and I'm just the guy to make you do so! ;-) Hang in there -- we're all in this together!! 8) --Keith :mrgreen:

Ok, sorry for the delay in updating this thread... I've just received two official brochures in .pdf format, from Daikin and Hitachi. Unfortunately they're in italian, so I'll try to summarize what they say. They refer to the Daikin Ururu-Sarara series and the Air Exchanger series by Hitachi. The technical names are the ones I wrote in a previous post. Both units have been showed at an Expo in Milan, end of March. The Ururu Sarara will be available in July. Both are monosplit, inverter, R410A, heat pump (heating and cooling) units. The Daikin comes in three sizes (2.8, 4.2 and 5.0 kW cooling), the Hitachi comes in 2.5 and 3.4 kW cooling capacity. The Hitachi shows an impressive 20db of internal unit noise (at minimum) which is the best I've found up to now (the Mitshubishi was 26 db). Both units have automatic and/or manual air exchange capability to taking exhaust air out and fresh air in. The Daikin claims a 28m3 of air exchange per hour and it also has a humidity control function. Unfortunately the Daikin will not be sold or distributed in US and Canada, so the hunting is open for the Hitachi... 8) This is a link for the Hitachi operation manual: http://www.hapm.hitachi-asia.com/index/ ... 5_35JX4(EN).pdf

Wow, I was really impressed with that unit, until I read this on page 18: "The fresh air in and exhaust cannot be operated simultaneously." That to me (and I'm sure to my building department) is a dealbreaker. To be able to run the unit to supply the room with fresh air without being able to exhaust the air entering the room with a similar amount of force will cause the room to become somewhat pressurized. The opposite is true of exhausting air without fresh air coming in. This is especially true if the room is air-tight, which if you build it properly, it will be. Again, my plan for ventilation calls for two fans working together in the same unit -- one for blowing air in and one for sucking air out. That's what you need in order to provide the amount of air exchange necessary to satisfy code requirements for replacing a window. Although this Hitachi system is surely the closest I have seen to the "magic system" that I gave up on finding, it is unfortunately not the holy grail of mini split systems that I was hoping for. If I were in the market for one for a home or office, though, yeah, I would definitely put that on my list of contenders.

Well. just to let you know, I've ended up with the Mitsubishi Electric MSZ-A09NA. I will take care of the ventilation somehow but I just want to tell you that the result with this unit, especially in terms of quietness, has been largely beyond my expectation. In normal operation the unit is practically inaudible. Yes it's pricey (4.000 canadian $ including installation for a 9.000 btu heat pump inverter) but it's worth it. :D

Why not look for a tube-fan, use a duct splitterpipe for multiple in/ex haust entries/exits. Those are cheaper than those boxes. On can obtain a fan for about 150$, depending on the max air load. That don't have to cost 4000$ all together. But I'm talking European (dutch) prices here, dunno what such will cost in the USA for example.

Steve's unit is a mini split air conditioner and heat pump. It provides no fresh air ventilation. It's also equipped for use in cold weather to prevent freeze-over. That's why it's so expensive -- that and the fact that it's probably the best mini split manufacturer in the industry -- made in Japan. I'm glad your experience with the unit is great, Steve. I'm planning to get the cooling only version of that for my space. --Keith :mrgreen:

aah, sorry my mistake. Didn't quit understand it must have airco and heating options. YEah, well that sure makes it a lot more expensive.

Mits can be flakey however. I am late to this one, but someone mentioned heat. HAH!!! With my G5 idling in the dead of a Michigan Winter (just as cold as NH) close the door and man it gets hot in the studio. I found myself over the past 3 years having the AC running year round.

Has anyone found a US source for the Hitachi Air Exchanger or the Daikin Ururu Sarara? I've looked online for hours and not found anything. Lots of good info in Europe/Asia. Either unit would be great I think. Is it possible to have a unit shipped from Europe? Propably prohibitively expensive, but .... These units look ideal for me. It seems to me that providing exit ventilation (if necessary) out of my space would be much easier than a full ventilation system.