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Any of you builders, GCs, building inspectors and HVAC installers work to specific codes that deal with HVAC? What code applies in your area? I know what codes apply to commercial, industrial and institutional buildings. The same doesn’t apply, unfortunately for the occupants, to residential.
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Tim, now you have done it! I have to get out my KY code book and see what the different standard are for comercial and rsedential. Two guys I work with hold thier master license. We only work on our own facilities (comercial), so I have never look at residential codes. I'll get back with you after the holidays.
Happy holidays!
Dave
*Dave,Hope that you had a good Christmas, and thanks in advance for looking. I don't know what a master license is or what it take to get one. I am assuming that you're talking about Kentucky although it seems that with some codes, KY might ease the use...I want to know know who out there involved in building houses know what code applies to ventilation (or will admit to not knowing or not caring). The electricians all have at least a familiarity with the NEC (and many I've dealt with know it well) and whatever local codes apply. The inspectors of houses can usually tell you if drains are vented per the code and wiring meets their requirements.I am guessing in some instances but I know there are many "posters" out there that have ideas and knowledge on this issue. Bob is a home inspector. Rob is associated with "healthy homes". Dave has got energy efficiency down, knows engineering and plumbing.
*Hey Dave - Where you watching THE game this Saturday? Maker's Mark came out with a collector bottle today to memorialize UK vs. URP (University of Rick Pitino).
*Tim, in KY you enter the HVAC trade as an apprentice and are reguired to work 3,000 hours for a master to be eligeble to take the test to become a journeyman. The hours can be reduced to 1500, if the apprentice goes to a certified trade school. A journeyman must also work for a master the same number of hours and/ or attend continueing education classes to become elegable to take the test for his masters license.A master must attend continueing education classes every year ( 16-24) to maintain his license. A master is the only one that can pull a permit to install and service HVAC equipment. In Jefferson county there is a seperate inspection for HVAC, this includes hydronic heat as well as forced air systems. The master HVAC mechanic is responsible for any job his people work on, and must show proof of insurance for both liability and workmans comp. just to pull a permit. All of his employs must have the EPA recovery certification to break into a system.The master license requirements in Jefferson Co, KY also extends to the Electrical and Plumbing trades. there are no such reguirements for a GC. Alan, my family's christmas gathering is this Saturday and it has been dereed that all will go on hold for the duration of "the game". I will run home and watch it in the relative quite(we have a 5 year old) of my home. With almost 40 people gathering in my family, it is almost like going to Rupp arena or Freedom Hall, but the TV screen isn't big enough to support the crowd.I am not annal about sports, so I don't get as wrapped up in it as some do. It is just entertainment to me.Dave
*Tim,In Ohio, the Ohio Building Officials Association One, Two and Three Family Dwelling Code HVAC stuff is based on:BOCA National Mechanical CodeCode For the Installation of Heat Producing AppliancesStandard Gas CodeStandard Mechanical CodeUniform Mechanical Code
*Bob,I looked at these codes and didn't see much in the way of "hard" requirements. Familiar at all with the International Mechanical Code? BOCA is fairly useless and I don't know enough about the UMC. Never even heard of the other 3. Basic Mechanical Code and National Fuel Gas Code, I've heard of.IMHO, as long as the building industry is subject to meaningless and/or useless codes, HVAC is at the mercy of the installers.
*Tom,You're right.Heck, I'm just a home inspector and see a fair number of bad and questionable installations, but it can be tough to argue with the "experts" with such loose requirements.Fortunately, there are some very good HVAC people in my area that I can use as backup experts.I'm not familiar with the Intern'l Mechanical Code; I'll have to check that out.
*Bob,Ever see a house with outside air ducted to the furnace or in some way provided to the house? The code I am familiar with (IMC) and that applies where I work requires it in residences. Nobody does it. Nobody cares. Exhaust in bathrooms seem to be a "nicety" not a requirement.Iv'e noticed from questions asked and posts made, that most don't know, understand or really care about ventililation.
*Tim Im reading your stuff with great Intrest and you are right we are building in Long Island and no one really knows > I am at the mercy of installers and only hope that People like you can help us out.You already answered one of my questions I posted some more. Wouldn't it be great if their WAS some unbiased way to get the real total Info..... Thanks George
*George,Design of your system depends on which code(s) apply. The basics of the system I covered on the thread you created, but the specifics depends, to some extent, on the code. For instance, is fresh (outside) air a requirement in your area or an option? (To me, it is never an option) Does the building or energy code require a certain SEER or AFUE for the equipment (the mech codes I am familiar with do not dicatate these requirements).Ask the contractors proposing work for you what codes apply. A good screening for them. Ask them how much fresh is required and how much they intend to provide. Blank stares, no work. (I bet the one that proposed 12 tons is completely clueless on codes.)
*Tim,Most the new construction I see uses direct vent 90+ with outdoor supply.Some, of course, don't hook up the supply pipe.I've asked local heating folks if they performance test their installations. Most give a blank look or respond: "Why? It's new!"I tell 'em it was new when it left the assembly line, which was a lot of bumbs and drops and jostles ago.Probably the most consistent problem I see are poorly drafting water heaters in houses 20/25 or less years old.I think in most csaes the houses are too tight.
*I disagree, Bob. Houses are not too tight. They all leak some, but less infiltration is better for a host of reasons. If gas burning appliances are not drafting properly it is because of some person did not fully understanding what needs to be done. The reason I asked the question was this lack of understanding of venting a house correctly. The International Mechanical Code specifies ventilation requirements for combustion air, that if followed, would eliminate the problem.
*Tim,Too tight? I don't know for sure; I'm looking at, say, 100 BPI protocol Carbon Monoxide Analyses (which is not a big bases, of course), and am especially thinking of the draft guage readings.In pre-mid 70's houses, I'll typically get poor drafting of a water heater when it's been orphaned in the chimney because of changing the furnace to direct vent. Second most likely is water heater and 80+ on a chimney with exterior exposure and no metal flue installed within the chimney.In Post mid-70's houses, a poorly drafting water heater is more likely, and in many cases, the draft will be reduced by turning on vent fans around the house, or increased by opening doors (although I have also seen the draft go down when a door (esp the garage door) is opened."too tight" seems to me to be the most likely explanation, but I freely admit that many of the things I thought would be true about venting & flues and which seemed intuitively true have proven not to be!I very much value your insights and knowledge in this area. (As a home inspector, I'm a generalist; this is one area where I want to be as knowledgeable as I can!)Question: there's been a discussion on a private home inspectors' forum regarding whether a utility closet (or other restricted space) can be both "fire-stopped" and vented to the attic.The various codes seem to be in contradiction, here.I think I've seen a requirement somewhere that the Hiher make up air source should be vented to the floor level.Are you familiar with this? Is it paret of the Int'l Mech Code?TIA
*Thanks Tim an Bob I have a Meeting on Saturday Morning with 1 guy The one That reccomended the 7 1/2 tons. I will ask the Questions as a matter of fact I printed them and will go with "First Hand Inquires".He has proposed a new System however. I have a Large room over the Garage almost380 sq ft. That I dont want to heat and A/C with the rest of the house. So He changed upstairs to 2 units A 3 ton with the Hamonoy Zoning for the master and other 3 bedrooms and a 1 1/2 ton for the extra room with its own Hot water coil. Better Worse I don't really know.. Tim I didn't want to go with Forced Hot Air Furnace. Ihave that in my current house and feel its just to severe. What I have read about Hydronic is that its a Gentler system. I really wanted to go with Radiant Floor heating but the cost was Prohibitive. almost 10,000 extra. I do'n think it warrents that much money but that was the estimates from 2 separate contractors.Finally all contractors are giving est. with one Humidifier on the main floor and want extra for a second one the top floor. Can one Humidifier handle the whole house or am I CRAZY to think that humidity on this type of system is as important on all levels. Any one Interested in My whole story can check it out I the Thin thread that I started. Also sorry I can't give any of you guys help Your way over My Head but people like me appreciate the help
*Bob,Makeup air has to be provided for any device that discharges anything outside. It is a simple matter of conservation of mass. When you see water heaters and furnaces, etc., draft poorly when it has to compete with other items in the house for air, it is reasonable to assume the house is too tight, based on the history of how thing were done in the past. But, would you rather rely on random inleakage into the house through construction joints, windows and doors, or maybe have someone plan for the air requirements of the devices and provide it in a controlled manner? It would be the electrical equivalent of using any piece of metal they find in a wall as a conductor. Then if the house burnt down, saying "the house was just too flammable". The installer of the appliance doesn't overlook the fuel supply, why should they be allowed to overlook the combustion air supply. Many, if not all, of the CO issues you see would be eliminated if ventilation in a residence didn't consist of only a fart fan in the bathroom. You said you've seen sealed combustion units with the combustion supply not connected. That seems to be a blatant disregard for good practice, occupant safety and manufacturers recommendations.On your other question, it is common to vent through fire barriers. In a residence, firestops could be penetrated and protected with a sleeve and a fire damper, though I would never expect this in a residence.It is not practical to bring all buildings into compliance with current codes and/or good practice. It is practical to expect that new structures (and all that goes into them) reflect a higher level of integration and planning than was done 70 years ago.
*George,Unless I misunderstand the systems your are looking at (furnaces with a hot water coil for heat and DX for cooling), you have a "forced hot air furnace". The only difference is that you are heating water with a boiler and using hot water to heat the air. Hot air is hot air.As far as the humidifier goes, a single humidifier will handle your entire house. The problem is that, with separate systems, it will not be able to serve the entire house. For many, (though I disagree with this) humidification is an option. You could install one on the lower system and be covered well.Back to the unit sizes. 1.5 tons for 380 sf (250 sf/ton) is way too much. If you want your AC to dehumidify your house, it needs to run. In mid Long Island, you will never see the temperatures to warrant 7.5 tons in a 3500 sf house, especially with the construction as you described. I like to see AC units on the small side, and in your case, I would still recommend 5 tons or may two 2 ton units to separate the floors. Since you are installing zoned systems, zone the room separately from the BRs.
*Tim,"You said you've seen sealed combustion units with the combustion supply not connected. That seems to be a blatant disregard for good practice, occupant safety and manufacturers recommendations. "Saw one unit a few weeks ago where I was concerned with the location of the flue viz a viz window.The manufacturer's installations were with the unit, so I took a look. FWIW, the installation instuctions apparently gave an option for connecting or not the intake pipe to an external source.I forget which manufacturer, but it was one of the nationals (Lennox?}
*I would bet there is some qualification of that "option". Bad practice no matter.What separation requirement is there between the window and the flue?
*Here, (Rockford, IL) the city just adopted the new International Building Code that replaces (or incorporates) BOCA. Anyone have any experience with this one?
*Hi Tim I posted another Question Thanks.Ifi you want pics of the house E mail me and I'll forward them.. George