I got this e-mail from Kevin this afternoon; he’s still weaning himself off the dreaded “B-TAS” (B-T Addiction Syndrome) so didn’t want to make things harder by dropping in to post this in person. But as you’ll see from his message, he feels it’s an important article for us, so he forwarded it to me.
FROM GOLDEN WRECKED ANGLE to ALL:
If you don’t mind posting something to Breaktime for me I would sure appreciate it. This article just came in an electronic concrete newsletter I subscribe to http://www.concretenetwork.com/anne_balogh/are_you_overheating.htm . I saw Blodgett’s question about overbuilding houses that are “too tight” in the Breaktime section of the magazine this month. IMHO, this article is an excellent response to the problems raised by Jim, and many of the responses.
I’m convinced that sick house syndrome is more often than not, simply poor HVAC design. Richard Rue, the source of much of the linked article, did the HVAC design on our house. Our energy bills are always less than half that of our neighbors with comparable sized, energy efficient homes, and our climate inside the home is ideal. The worst example is a friend of ours a few miles down the road who over-built a 2,400 S.F. SIP home fit for Alaska and then oversized their HVAC system and put in an air-to-air heat exchanger to keep the home “healthy.” They both work and have no kids at home so their primary energy load is at night. They routinely spend $500 or more per month on utility bills when we a writing checks for $100 to $160 with Jenny home, all day, most days, and a very active four year old putting the back door to the yard through 20 cycles or so an hour.
I’d like to think we did several things right that our friends did wrong but the biggest difference is that I hired someone to do the HVAC design that knows what they are doing when it comes to “tight” houses. I can’t stress the importance of the HVAC system design enough in building tight and healthy homes. Air-to-air heat exchangers are not the answer!
I promise not to make a habit of using you as a relay but I think this article is important and I’m not quite ready to drop back in and post it myself just yet. I would really like to see Richard Rue do an article for Fine Home Building one of these days. Say hello to the gang for me will ya? AH-Pree-Shate-Cha!
Dinosaur
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship…
View Image
But it is not this day.
Replies
That's funny, I was just thinking about him today and that house he built with the big smile.
I was wondering where he went and now that it is mentioned, I remember him leaving.
WOW! Musta been quite an addiction. I miss him!
Eric
It's Never Too Late To Become What You Might Have Been
[email protected]
Thanks dino. We pass the occasional email and it's always good to hear from Kevin. Because afterall, as my black debris hauler says after calling me kevin for a zillion times.............."calvin, I'm sorry................but all the white calvin's I know are named kevin". Can't argue with logic.
Kevin imparted an abundance of knowledge, had some good questions and was a reasonable mind in a mildly conservative way. Hopefully someday he'll be able to place himself in moderation as far as BT goes.A great place for Information, Comraderie, and a sucker punch.
Remodeling Contractor just outside the Glass City.
Quittin' Time
He's one wonderful man, well writen wordsmith, and multiply missed brother, but he has his priorities right.
addiction????? ain't no such...well......get back to ya later on that
Welcome to the
Taunton University of Knowledge FHB Campus at Breaktime.
where ...
Excellence is its own reward!
Yeah, and me? Addicted. Horsephooey. I'm enjoying sitting here with my teeth aching for my supper which I can smell from downstairs....
Uh, gotta go; soup's ready....
Dinosaur
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
You are not addicted, you are compensating...& that's a whole other thing! I recall you saying somewhere in the K A thread that being on BT helps keep you sane, & that's a smart strategy...& besides, you have given me, personally, some great advice.
Just keep on keeping on, as we used to say in the 60's...
Kate
You are not addicted, you are compensating...
I knew that! (Whew!)
Dinosaur
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
Went to the website mentioned: Well!!! 13,500 sq ft house at a cost of what $1,350,000 or higher. If I had that kind of money to spend on a house, I could have low energy bills also!!! R8 windows, geothermal heat pumps with AC, all south windows with large balconey overhangs to reduce heat gain, etc, etc etc. Man!!! To hold up a monster like this as an example of energy conservaation is a travesty!!! I hope the people on the "sustainable building" thread have a look at this one!!
Can't believe he feels air exchange units/strategies are not needed.
A huge volume of of at least 100, 000 cu ft ,or maybe much more if the ceilings are high, can aborb a lot of interior generated pollution moisture especially if only 2-5 persons occupy the house. But put these 2-5 persons in a 1200 sq ft airtight energy efficient bungalow and see what you get!!! If he's always working in this range of house, then what he says will not apply to the common person.
Started working in airtight housing in 1977 and installed my first off-the-shelf HRV in 1981. The biggest problems I see with HRV's is that they are oversized by some installers, the only ventilation installed by some hvac contractors (no other exhaust fans) , the general contractor usually always installs the "bare bones" stripped down units to the spec homes, and they are not understood by the homeowner. This is usually not his fault but the fault of the installer or GC for not taking the time to explain the unit, its purpose, its limitations and the fact that, in most cases, it does not have to run fulltime.
He. he. he...we ran into each other last week in a VERY unlikely place around here..I will respect his anonimiti, anonymin, anon...ah hell, his privacy. LOL Spheramid Enterprises Architectural Woodworks
"I don't think it's funny no more" Nick Lowe.
I will respect his anonimiti, anonymin, anon...ah hell, his privacy. LOL
Anonymity.
Anonymosity.
Animosity?
??
Now you've got me wonderin', ye old word buggerer....
Dinosaur
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
Back on topic, here's an exchange I had with Kevin via e-mail. I won't be able to relay posts back and forth to him from every post, but this will kick things off. Those of you who have his e-mail address can copy him your posts that way, or e-mail him your post through the board via one of his old posts.
DINOSAUR:
Interesting article; I wonder how it applies to homes built without central HVAC systems, such as mine. Woodstove heat with electric baseboard heaters as emergency backups for if I have to go away during the winter. The 'Air conditioning system' consists of lotsa windows and a 12" portable fan, LOL (I wanted to install a whole-house attic fan, but chickened out doing the ductwork I mistakenly thought I'd need, so...).
Do I take it that any 'superinsulated air-tight' structure necessarily needs central HVAC? If that is so, it takes them out of consideration for many country folk, I'd say....
GoldenWreckedAngle:
A super tight house is kind of like a cooler. Stagnant air needs to be dried out or exhailed or mold will grow. Heating does that pretty well, and even the best doors and windows leak enough to keep fresh air coming in and stale air going out in sufficiently healthy quantities so no, an A/C system is not essential unless the climate calls for it.
The problem is not the inhaling and exhaling of moist air - it is trapping that moist air long enough to let microbiology take over and give the contaminants in the air all around us a means to set roots and grow. By all means, throw open the doors and windows and enjoy the "fresh" air. It's good for you and your tight house too! We have several days out of the year where we can throw open the windows and enjoy the great outdoors here in Texas as well, but when we are forced to seal up the house and kick on the A/C for the humid summers, we need good engineering and science backing us up.
One of the main problems with air-to-air heat exchangers in a humid climate like Texas is that unconditioned and undried air is constantly being pumped into the house, while the filtered, dried and conditioned air is sluffed off in the interest of shedding contaminants. We literally do what our fathers used to get so upset with us over. "Boy, are you trying to cool off the entire neighborhood? Shut that door!" The fallacy in thinking is that the outside air is "cleaner" than the inside air. In reality, it is usually significantly more "contaminated," at least with the contaminants that lead to allergies, mold and bacteria growth. Coupled with short cycling, resulting in trapped moist air in the home, we are building the ideal conditions for large scale "moldy coolers."
The number one culprit in "sick houses" is probably short cycling mechanical systems. They kick on, blasting heat or cold in a volumous rush, then run just long enough to trip the thermostat but never long enough to actually "condition" the air in the home. It is flat out amazing how many gallons of water get wrung out of the air in our house every day. I ran the condensate drain from the downstairs air handler into a one gallon container for a while this summer. I had to empty it four or five times a day or it would overflow. The upstairs air handler was probably wringing out more than that. That water vapor in the air is the real problem. Why keep dumping more wet air into a house through an exchanger when you haven't even filtered and wrung the last batch out yet? Is that really going to make the air healthier?
Our heat pump is sized so that it has to run for a while when it does kick on. It actually gets into it's "efficient mode" and works for a while, drying and filtering the air we have worked so hard to "trap" in our tight house. I almost never have to run the bathroom fans to exhaust moisture or odors, even when I'm showering, and I haven't even hooked the down draft on the stove top up yet. Actually, that has been a problem on fried meals a couple of times when we had to open the kitchen windows to get the smoke out, but most of the time the air is clear even when Jenny is cooking, especially if the HVAC system is running. Of course, if I did most of the cooking, that exhaust fan might be more of a priority. (I've got to get that done one of these days)
In contrast, most people build well insulated houses then put over sized mechanical systems in them that kick on and off all day in start-up mode and run just long enough to actually dump the conditioned air through the exchanger, only to replace it with outside air that never gets thoroughly rung out and filtered. They go for the exhaust fan switch at every excuse too, sucking contaminated air into the house through every nook and cranny (mostly the closed doors and windows) as they exhaust the conditioned air from the home.
It boils down to the difference of traveling the same number of miles on the highway in a compact car vs. starting up a big block engine, driving a mile or so, then turning it off, only to start it up and run another mile or so a few minutes later. Which one introduces the most pollution and costs the most money to run? The tighter the house, the less work your HVAC has to do. The trick is to trap the air, then filter and condition it. It is usually a waste to throw that air away once you have succeeded in getting it all fixed up and "healthy." Size the HVAC so it can handle the reduced load efficiently, but most importantly make sure it runs long enough to actually wring the water and contaminates out of the air. The nicest benefit over healthier homes is that it will save you a bunch of money on that monthly energy bill.
Dinosaur
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
'minds me of an article I saw once, guy in Texas who got something like 90% of his potable water by trapping his AC condensate......
guy in Texas who got something like 90% of his potable water by trapping his AC condensate
Ok, that's slightly scary on several levels.
Note I did not say impossible <g>.
May be apochryphal, though. The places wet enough to collect water in a large enough volume to make it worthwhile already have water enough. Get out in the Panhandle, or out West, and it can be a different proposition ("humid" in Lubbock is RH over 15-20% or so; that's "dry" for my county, very dry).Occupational hazard of my occupation not being around (sorry Bubba)
Hey Capn', don't think it was a lack of local water sources that did it...think he was just a transplanted Yankee who figured all that water might as well get used.....
ust a transplanted Yankee who figured all that water might as well get used.....
Having seen what drips off both the coil, and the coil surround, I'm not sure I'd water with it <g>
But that may be too much exposure to cleaning both pan and coil drains after they clog . . . Occupational hazard of my occupation not being around (sorry Bubba)
something like 90% of his potable water by trapping his AC condensate......
That's no trick if you restrict your potable water requirements to making coffee, or ice-cubes for the whisky....
In this area, air-conditioning can be seen as a luxury...if the house is designed with that vision in mind from the git-go. Unfortunately, the 'murrican dream McMansion mentality has walked all over that kind of design vision, and it is a rare place that's conceived of to be comfortable without some sort of artificial cooling help.
We obviously can't live in sealed boxes, not unless we are willing to have CO2/O2 exchangers built in so we won't suffocate on our own waste gasses. Say, a big spread of hydroponic plants of some sort in the basement. (But there are other issues with some of those installations, LOL....)
Permeability can be controlled to some extent by choices of window and door type, and VB type. But the assumption in our codes is that if a house is built up to current insulation and air-tightness standards, an air-to-air exchanger will be needed, so it is now a code-required item for all new construction. I disagree with this requirement. I think it directs basic house design into politically-correct but realistically-flawed directions.
When my woodstove is burning full-tilt--as it will have to be in a few minutes, it's gittin cold up here, darn it--it draws its own make-up air quite well through the shell of the house because I chose to use old-fashioned foil-backed kraft VB on the first floor. In summer, when heat is a problem instead of a goal, this place remains cooler than most others because it has wide porch roofs that keep the sun off the first-storey windows...and reflective shades I can draw on the south-facing windows of the second storey. I only have to open a first-floor window once or twice a summer on really bad days; normally I keep them closed tight and draw fresh air in through the cool basement, up the central stairwell--deliberately designed to have a chimney effect--and thus to the second floor bedrooms, where it flushes out the hotter air that has accumulated up there and makes things quite comfortable in jig time.
Why should I be obliged to put in an air-exchanger, or to build my house so tight I would actually need one?
Dinosaur
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
Hey, what else is potable water for......
Ouch, I didn't know heat exchangers were now code required......
I try every summer to convince my wife to move into the basement when summer rolls around..sort of like a mini-migration...but she just turns down the AC...sigh
Like the chimney effect idea....my stairwells are are perpendicular to each other, so it wouldn't work, but maybe someday I'll play with my return vents to draw basement air in in the summer & spit it out upstairs
Hey, I picked up some left over foil face FG batt recently, haven't seen it sold in awhile...wonder why, wonder what the "Building Science" take is on it vs. paper faced?
Heat exhangers are not required by code; there are 6 methods of meeting the ventilation requirements of the Canadian code of which the off-the-shelf HRV is one. The others require some design skills and sometimes having heated supply air for certian exhaust configurations and equipment.
Quote: " picked up some left over foil face FG batt recently, haven't seen it sold in awhile...wonder why, wonder what the "Building Science" take is on it vs. paper faced?"
The building science take on it is that if the trades had gotten trained in the field at the time the discoveries wre being made, we wouldn't have any of this "faced glass" for walls.etc stuff since about 1965. In Canada, I can't remember it being available since the mid to late 1970's. (Note: I've been in the insulation/energy conservation business since 1977)
well, in building science land, everyone has rain walls, sip roofs or sprayed foam rafter bays, geothermal heat pumps, etc.
I've been building about as long as you have, & still don't know what to do with my current abode...
Buffalo NY, cape with a 2nd floor buildout, cathedral ceiling in the master, insulation shell is the floor bays, up the knee walls, & over the attic ceiling
Standard (IMHO mostly useless) ridge vent but no eave vents & no overhang to put them in
Ice dams to beat the band!
I've foamed up all the various stack penetrations, am slowly adding a second layer of unfaced bats across the existing bays in the attic (yeah, I know , I should be filling it up with 12 " of blown in cellulose)
I've thought about trying to modify the existing fascia boards -strip the gutters, wrap sheet metal over some Coravent material & use it as fascia, so I get some eave vent flow, but hey, the snowmelt already freezes at the gutters, so more venting would probably just make the ice-damming worse, & not do much for cooling in the summer....
Realistically, unless I gut the second floor & spray foam the whole thing (can't afford that)
or strip the roof & make a cold roof (can't afford that, either & wonder just how much sense those assemblies make if you're topping them with 25 year shingles), I think what I'm doing is better than nothing, & has some benefit at a cost I can bear.
All in all, it nags at me, but mostly I just try & rake the bigger snowfalls of the roof when I can, & keep the set back t-stat programed & the 90% furnace tuned up....
This is a detail for venting the rake edge of an insulated cedar-shake overroof job that I designed for a client. If you take that detail and wrap it around your eaves, building out by 2 inches and using sub-fascias and finish fascia to hide the vent strip underneath, you'll be all set. And decent sheet-metal fabricator can make you U-shaped perfed strips from 2" wide on up fairly cheaply.
And you are right; ridge vents--especially in your climate, LOL--aren't worth the paper to wipe their...uh I mean, "the powder to blow their noses."
View Image
Dinosaur
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
Nice drawing, thanks....what's it done in?
but that's what drives me nuts.....you agree with me re ridge vents (at least in their min. code implementation, but send me a detail on eave vents....
So, friend, why would I tear up my fascia & reroof, insulated or otherwise, to put in eave vents that don't have a corresponding ridge vent?think I'll just build an igloo, till GW queers that lifestyle (G)
So, friend, why would I tear up my fascia & reroof, insulated or otherwise, to put in eave vents that don't have a corresponding ridge vent?
Because that detail shows you how to vent the entire rake edge, which, combined with eaves venting done the same way, and the fact your new roof deck would be floating ¾" above the insulation, would give you a cold roof. If you have doubts about it being cold enough, install a wind turbine ('Charlie Noble') at or near the ridge, and build a nice-looking cupola over it to dress up the whole affair.
Dinosaur
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
Edit to add: The drawing was done using ACAD R14, but that's a screen-shot I saved with my photo editor as a jpg. It comes out clearer that way than using the conversion program.
Edited 11/3/2005 12:45 pm ET by Dinosaur
Ah, missed the rake edge detail....
No problem. Just remember I designed that over-roof job with skip-sheathing over the crib holding the insulating panels because it was for cedar shakes. For a standard asphalt shingle job, you replace the skip-sheathing with 1x3 strapping over the crib, on 16- or 24-inch centers, then nail the plywood sheathing to that. Use ½" or 5/8" ply depending on the spacing of the strapping and the slope of the roof.
When you set it up that way, the eaves and rake edge details shown will provide full air-flow under the entire active roof deck (the old one underneath the insulation no longer counts, because no snow can land on it).
Dinosaur
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
Edited 11/3/2005 5:43 pm ET by Dinosaur
Heat exhangers are not required by code; there are 6 methods of meeting the ventilation requirements of the Canadian code of which the off-the-shelf HRV is one.
Thanks for the clarification on that; my copy of the NBCC got 'abridged' in that I traded the $125 bound book for a Senco framing gun from a guy in the States who wanted to advertise that he 'built to Canadian standards.' So before I shipped it off, I photocopied the tables and Chapter 9 and the annexes that I use all the time, but not much else....
Dinosaur
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
Poor guy in the US. I wouldn't build to Canadian standards. "A Guide to the Use of the Code" at the front of the 1995 version (that is still valid in most jursidictions today; the new model code was released in Sept/05 states:
"The NBC is essentially a set of minmum provisions for the safety of buildings with reference to public health, fire protection and structural sufficiency. It is not intende to be a text book on building design, advice on which should be sought from professional sources."
For example: in Part 9 (houses and small buildings) Sect 25. (Heat Transfer, Air Leakage and Condensation Contro) l2.1.1) - Required Insulation states:
All walls ceilings and floors separating heated spaces from unheated spaces, the exterior air or the exterior soil shall be provided with sufficient thermal insulation to prevent moisture condensationon on their room side during the winter and to ensure comfortable conditions for the occupants."
No minimum levels stated. How do I feel about the code??? It's the least that we'll let them get away with!!!!!!! or as someone on another thread here says:
Bad builders build to code; good builders go beyond. ( or something like that)
"The NBC is essentially a set of minimum provisions for the safety of buildings with reference to public health, fire protection and structural sufficiency. It is not intende to be a text book on building design, advice on which should be sought from professional sources."
Actually, I consider that a fairly encouraging statement, in that it shows the code authorities for Canada do not consider themselves to be God, unlike code authorities in many other jurisdictions (including some of the local yokels around here, LOL).
When code starts interfering with design by being too specific in its requirements, that bothers me. My view of the legitimacy of a building code that is enforceable by a public authority is that it should address exactly what your quote states: minimum provisions for the safety of buildings with reference to public health, fire protection and structural sufficiency. Anything outside that mandate is the guvmint stickin its big fat paws in where they oughtn't be stuck, IMO....
That said, I will agree that some of the code provisions in the 95 NBC are well below what I am comfortable building...such as the specification of 3/8" OSB for roof sheathing over trusses/rafters on 24" centers. Eeewwwwww.... But until the code prohibits me from building better than their specifications, I don't have a moral problem with it.
Dinosaur
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
DINO: A bit of response to ANGLE:
A super tight house is kind of like a cooler.
I have seen some very tight, highly insulated homes become "solar cookers during the summer into the early fall due overuse of glass on the south
Stagnant air needs to be dried out or exhailed or mold will grow. Heating does that pretty well,
Stagnant air does not necessarily have to be dried out unless the relative humidity (RH) is up over 65-70% on a longterm basis. This is the critical ambient humidity at which mould, mildew, fungus will start to grow without having a spill/leak leading to wet/soaked materials.
Heating does not dry the air out. The same absolute mass of water is still in the air. Raising the house temperature by 3-5 degrees, as is the average house temperature rise in a heating cycle (unless from setback), does lower the RH by 10-15% so it feels drier.
and even the best doors and windows leak enough to keep fresh air coming in and stale air going out in sufficiently healthy quantities so no, an A/C system is not essential unless the climate calls for it.
If your best windows and doors still leak that much air then they must be quite loose or else other areas of the house still have leakage you don't know about. Has the house had a blower door test done on it?????
The problem is not the inhaling and exhaling of moist air - it is trapping that moist air long enough to let microbiology take over and give the contaminants in the air all around us a means to set roots and grow.
Trapping the moist air is not a problem unless the RH gets up over 65-70% for long periods. In cold climes, airtight houses with HRV's can get overly dry in the winter if the HRV is too big or used more than is needed for good air quality.
Contaminants are not only microbiological moulds but bacteria/viruses that we produce, can be invisible dust, volatile organic compounds (formaldehyde, etc) from building materials, cleaners, waxes, etc. So even if the moisture isn't getting too high, there are times that air exchange may be a good thing.
By all means, throw open the doors and windows and enjoy the "fresh" air. It's good for you and your tight house too! We have several days out of the year where we can throw open the windows and enjoy the great outdoors here in Texas as well, but when we are forced to seal up the house and kick on the A/C for the humid summers, we need good engineering and science backing us up.
True! there's no need to run an HRV/air exchangers fulltime when the outdoor air at the right temp can supply the exchange we need for free. And we do need good design and execution of the plan for our HVAC stuff to work well without costing us in other ways such as cooled, damp air from an oversized A/C.
One of the main problems with air-to-air heat exchangers in a humid climate like Texas is that unconditioned and undried air is constantly being pumped into the house, while the filtered, dried and conditioned air is sluffed off in the interest of shedding contaminants. We literally do what our fathers used to get so upset with us over. "Boy, are you trying to cool off the entire neighborhood? Shut that door!"
Unconditioned and undried air does not have to be brought into the house constantly. Only enough air is needed to take care of an indiviudal family's needs. The HRV may only need to run 4-6 hours per day or less- put it on a programmable timer. There are HRV's with dessicant wheels that can reduce moisture in the incoming air by about 50% and recover 40-50% of the outgoing coolth from the air (these #'s are from memory and may be a bit off) . This is better than doing nothing to the air that's leaking in the best windows.
The fallacy in thinking is that the outside air is "cleaner" than the inside air. In reality, it is usually significantly more "contaminated," at least with the contaminants that lead to allergies, mold and bacteria growth.
Unless you're living in a city center or an industrial area, the outdoor air is usually better than the indoor air in houses without air exchange or high efficieny filtration. ( and speaking of the indoor air, it started as outdoor air and then we started adding our indoor pollution to it, so its not likely to be better)
In the 1960's, researchers went into housing in the steel belt areas to sample the air. They were afraid that the local air with all its dust and other contaminants was going to start affecting people. Much to their surprise, the indoor air was worse than outdoor due to the #'s of cleaners and other chemicals (pesticides, sprays) we were using and storing inside. AZh the great chemical generation was beginning!
Yes, outdoor air does contain natural biologicals; these do not usually lead to allergies, etc but certainly can aggravate these conditions. Some of these conditions are congenital; others seem to be acquired. It is believed that children growing up in sterile environments do not have their immune systems challenged enough to develop strong reactions. A small study that just came out followed farm children who got into it up to their eyes- manures, pollens, musty hay and silage- it showed that they had less allergies, etc!!!! Or could it be that they were of better genetic stock. More study needed.
Oh by the way, if you don't want to bring a lot of crap into your home, take your shoes off....... outside- researchers found all the stuff you're afraid of on the souls plus oils, pesticides.....you name it.
Coupled with short cycling, resulting in trapped moist air in the home, we are building the ideal conditions for large scale "moldy coolers."
The number one culprit in "sick houses" is probably short cycling mechanical systems. They kick on, blasting heat or cold in a volumous rush, then run just long enough to trip the thermostat but never long enough to actually "condition" the air in the home. It is flat out amazing how many gallons of water get wrung out of the air in our house every day. I ran the condensate drain from the downstairs air handler into a one gallon container for a while this summer. I had to empty it four or five times a day or it would overflow. The upstairs air handler was probably wringing out more than that. That water vapor in the air is the real problem. Why keep dumping more wet air into a house through an exchanger when you haven't even filtered and wrung the last batch out yet? Is that really going to make the air healthier?
The short cycling is the oversizing of the A/C and has nothing to do with an HRV or the efficient house. So get good design done and don't blame the HRV or airtight house
As I mentioned at the beginning of this thread, GoldenWreckedAngle is still on a 'sabbatical' from BT for a while yet so he won't see your post unless you copy it to him.
If you want to copy your post to him by e-mail you can do it through the board's blind e-mail function via this link: http://forums.taunton.com/dir-app/bbcard/bbSendMail.asp?webtag=tp-breaktime&cType=2&uName=wreckedangl1&dMode=1&eBtn=0&uid=365403873
Dinosaur
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.