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  1. #1
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    Default Anyone have experience with these?

    This Humidistat was from a home built in 1970 in the Dallas area. I believe it was connected a device that "Misted" or sprayed water into the air ducts when the furnace was on to add some humidity to the dry furnace air. The entire HVAC system has been replaced and along with it, the humidifier is no longer installed. I do not see these on modern homes, only on homes from the 70's or older. I assume these were a fad because like I said, I never see them on new houses in the Dallas area. Only the Humidistat control is left on the wall. I am just wondering if anyone has photo or diagram of the way the humidification system used to look so I could get a better understanding of how it was supposed to work. I am only guess that it was to add moisture to dry furnace air. Anyone have a HVAC humidifier diagram they can share? Or can educate me on what I believe to be true about this type of system. See photo. Thank you. Gene

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    Default Re: Anyone have experience with these?

    Do a google search for "furnace humidifier''.

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  3. #3
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    Default Re: Anyone have experience with these?

    I have humidistats on my 2001 Carrier/Bryant heat pumps but did not opt for the actual mold generating device or whatever its called.

    Many new systems can have this but a seperate wall control is not used unless it was some sort of add on device.

    The older houses I have seen those on also had them disconnected at the moldy airhandler.

    Bruce King, B.A. King Home Inspections, LLC
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  4. #4
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    Default Re: Anyone have experience with these?

    From the Texas Standards of Practice

    (e) Specific limitations for the heating equipment, cooling equipment, duct system, chases, and vents. The inspector is not required to:

    (1) program digital thermostats or controls;

    (2) inspect:

    (A) for pressure of the system refrigerant, type of refrigerant, or refrigerant leaks;

    (B) winterized evaporative coolers; or

    (C) humidifiers, dehumidifiers, air purifiers, motorized dampers, electronic air filters, multi-stage controllers, sequencers, heat reclaimers, wood burning stoves, boilers, oil-fired units, supplemental heating appliances, de-icing provisions, or reversing valves;


  5. #5
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    Default Re: Anyone have experience with these?

    Aqua-mist humdifiers were a combination spray nozzle and evaporative pad humidifier with a pan, usually located in the hot air side of a forced air furnace system trunk or plenum.Most misting, atomizing and centrifugal type system humidifiers went by the wayside after the source of "legionaire's disease" became known and word got out to the masses that this type of system was a breeding ground for such health hazards. Most of these were plumbed in via a saddle valve using copper tube to supply the water. As the years have passed most such systems have long since been gunked up, clogged, brittle, pans broken, etc. and most furnaces of that vintage have since been replaced. Most properitary sized evap pads, drums, etc. from such systems also not made, few outlasting years of cleaning with acid to remove scale, the Aqua-mist, misting nozzles wouldn't have survived, especially hard texas water. Many if not most local plumbing codes prohibit saddle valves for potable plumbing now as well.


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    Default Re: Anyone have experience with these?

    By the way, Honeywell made/makes humidistats some propriatary for manufacturers, the pictured appears to be so for Aqua-mist, Inc. (NC, IIRC) I'm not sure they are still in business, as "aqua-mist" seems to bring up things for hydroponic grow-ops now.A quick search of google books brings up some (most) viewable images from a book named Practical Heating Technology - around pgs 390-405 you will find pages devoted to various types older technology humidification systems.In a dry central heating environment, up north, in a older home, most newer systems include a temperature sensor/control for the outdoors, and adjust humidity levels accordingly, so as to avoid dripping windows, etc. A bypass type return side is more often seen post "legonaires".If you're looking for wiring diagrams for the humidistat - check honeywell site.


  7. #7
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    Default Re: Anyone have experience with these?

    H.G. That was exactly the type of historical perspective I was looking for. Thank you.

    Gene


  8. #8
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    Default Re: Anyone have experience with these?

    Anyone have any information for, Age of Air condition units, Water heating units.
    Thank you.

    Yahoo!


  9. #9
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    Default Re: Anyone have experience with these?

    Hey H.G., can you shine some more light on the "Many if not most local plumbing codes prohibit saddle valves for potable plumbing now as well." That is one I've not yet heard and I'd like to check my area.. thanks.


  10. #10
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    Default Re: Anyone have experience with these?

    Quote Originally Posted by kenny martin View Post
    Hey H.G., can you shine some more light on the "Many if not most local plumbing codes prohibit saddle valves for potable plumbing now as well." That is one I've not yet heard and I'd like to check my area.. thanks.
    Kenny Martin,

    Missed your post initially, as I hadn't visited my "ignore" list since you spouted off with some nastiness awhile ago.

    I'll leave you to your own research, for just what "LOCAL AREA" since "your area" is according to your profile "location" somewhat confusing.

    First off, states that use an IPC based plumbing code (the majority) they are expressly prohibited in the unammended IPC.

    Using a saddle tee valve to supply a humidifier, especially with the contamination possibilities of legionella, etc. is just IMO plain stupid.

    Kentucky uses its own authored plumbing code, and substitutes it for its version of the plumbing chapters of its adopted residential code. KY state plumbing code is mute on the subject of expressly prohibiting self-piercing or tapped saddle tee valves/needle valves on potable distribution/supply plumbing, however since for 1-2 family non prefabricated enforement is left to local enforcement, wouldn't know if local ordinance or rules speak to the subject. Some locals will deem violation of having been sealed to water and gas, or allow as a perm. method.

    IIRC Indiana state is using 1997 UPC with Indiana ammendments and substitutes IT for the plumbing chapters of Indiana's Residential Code (based on 2003 IRC with Indiana ammendments). I believe they have set in place use of 2009 IPC sometime next year. If I further recall correctly, local jurisdictions in IN further may adopt other codes, which where more restrictive apply - and several reference an ammended IPC.

    Do not know if your "area" extends to So. OH.

    Many states which have adopted various editions of the IRC have substituted plumbing chapters for either their version of the IPC (usually amending the scope to include residential), UPC or their own authored plumbing code.

    The unammended IPC specifically prohibits these valves on water supply/distribution, under prohibited joints and connections section 605.9 (4).

    Georgia, for example ammends this prohibition to allow in 1-2 family residential for supplying a refrigerator/freezer icemaker/water dispenser ONLY (not a humidifier), IIRC, they do not allow "self piercing" type, only those which are manually tapped.

    Self-tapping/piercing saddle tee valves often have a disimilar metal "tap spike" usually steel, which often corrodes. Some saddle tee valves are not self-tapping, the ferrule may or may not be a compatible metal for example a galv. water pipe system. No reason to use with other forms of plumbing. Now with shark-bites and other DIY friendly systems in addition to compression - there are many ways around solder/brazing in a proper tee and valve.

    The best way is of course to form a proper connection, tee or otherwise, and install a proper valve. When a saddle valve fails or the rubber grommet fails/leaks there is no way to isolate the area, short of cutting off the supply to the entire branch or in some cases, the home itself. Needle valves in general, are notorious for post single operation failure (won't shut off after intital installation, especially if time has passed), and leaks from packing, movement, etc.

    Saddle valves are notorious leakers, fail to work (valve) as intended, and sources for contamination, especially via the stagnating water line and the low-flow, occasional or unused line termination. They are also notorious clog/scale points. Most show signs of corrosion and/or errosion and leaks. The vast majority are not listed or tested, and those few that are, only for LEAD containing standards (many do NOT meet low lead standards).

    Due to the risk of failure, cross contamination between appliance or appurtuance "valve" and stagnating water to leakage/corrosion point of saddle tee valve conneciton - leakage, and inability to SHUT OFF should valve itself fail (such as when subjected to stress from turning valve, rubber grommet/gasket fail, nut or clamp nuts losening, etc., damage to property, they are enough of a concern, even where legal, to note in a report. The vast majority out there do not meet lead content standards.

    They are not allowed to be concealed. The vast majority have been installed by DIYers, appliance delivery/install agents, and upon occasion HVAC technicians. Usually without a plumbing license, or in consideration of the plumbing codes, and IMO are at minimum a nusiance.

    Last edited by H.G. Watson, Sr.; 10-12-2010 at 11:44 AM.

  11. #11
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    Default Re: Anyone have experience with these?

    First off; Humidifying in Texas because of dry air?

    Utah has dry air and these type of humidifiers for warm air furnaces are very common and still widely available and effective.

    The saddle tap to water piping is also common and acceptable for humidifiers and evaporative coolers as well as refrigerator ice makers. Ever visit Home Depot or Lowes? Ice makers, evaporative coolers and evaporative humidifiers have an air gap that eliminates cross contamination of the water making the tap a legal and efficient connection.

    As far as cleaning and maintaining they are a pain. But they work.

    Last edited by Rod Butler; 08-06-2012 at 08:23 AM.

  12. #12
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    Default Re: Anyone have experience with these?

    Quote Originally Posted by Rod Butler View Post
    First off; Humidifying in Texas because of dry air? Pahhhlease!
    Agreed, humidifiers in Texas were installed by transplanted Yankees or Natives that were on crack. Nothing but a mold factory and a leak waiting to happen.

    Jim Luttrall
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  13. #13
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    Default Re: Anyone have experience with these?

    Quote Originally Posted by Rod Butler View Post
    First off; Humidifying in Texas because of dry air? Pahhhlease!

    Utah has dry air and these type of humidifiers for warm air furnaces are very common and still widely available and effective.

    The saddle tap to water piping is also common and acceptable for humidifiers and evaporative coolers as well as refrigerator ice makers. Ever visit Home Depot or Lowes? Ice makers, evaporative coolers and evaporative humidifiers have an air gap that eliminates cross contamination of the water making the tap a legal and efficient connection.

    As far as cleaning and maintaining they are a pain. But they work.
    1) IIRC Utah adopted the IPC sometime back about a decade ago or more when they departed from the UPC and UBC and took on the I-codes. I do not recall at the moment if Utah in its having adopted the IRC has adopted the plumbing chapters and/or if it refers to the IPC.

    2) Unammended IPC expressly prohibits in Chapter 6; Section 609.5 number 4. Whether or not Utah has changed that language, and/or modified the scope in Chapter 1 of the IPC so as to include 1-2 family dwellings, I did not research, as neither the OP, nor the subsequent poster questioner are from Utah.

    3) Sure. And if you bothered to check you can find lots of "plumbing" items for sale in stores in many parts of the country, which are neither approved, nor code permissible to install. In fact, just the other day, side-by-side were two toilet flush valve assemblies by the same manufacturer - two different product codes, catalog numbers and inventory numbers/prices - one with approvals and "anti-syphon" features, the other without. AFAIK only two states - California and the other up east (can't remember if I'm remembering CT, MA or NH) prohibit the SALE of a potable plumbing system valve, faucet, etc. that doesn't meet Lead Free or local (California's state standard is more stringent than NSF 61) for SALE. Using the same type of example, you can find wire spiral plastic corregated thin plastic and foil so-called "dryer exhaust vents" or "dryer connectors" for sale pretty much all over the country too, doesn't mean they are legal or safe to install or use. You can also find lead content solder - so on that note, I don't "get" your point (quoted in red bold highlight).

    4) Few are tested/certified to reduced lead content standards (IIRC NSF 61). I have YET to see a manufacturer's assembly tested, certified or approved to OTHER than just low-lead content standards. If you are aware of one, please advise. I would be very interested to see whose saddle tee valve has such an acceptance/approval for this purpose (of modifying the potable water supply/distribution system.

    5) The contamination issues discussed are NOT at the point of connection to the appliance or in the case of a humidifier, the appurtuance - they are at the connection of the tapped valve itself - at periods of lower pressure, and when either the "tap", the ferrule, or the rubber/elastomeric/etc. gasket fails. You also can have issues with corroding and decomposing tap dissimilar metals as already mentioned, gasket, and materials such as collections of minerals/scale collecting and clogging the NEEDLE tap. During off-seasons you also have the issue of a DEAD END. ON TOPIC to the original POST which was pertaining to an AQUA-MIST humidifier and its control, MISTING type humidifiers are recommended against in forced air furnace systems and have been for a long time.

    6) Self-tapping cannot be used on galvanized - must be pre-tapped; Copper tube the self-tap point will quickly corrode due to dissimilar metal. Most foreign made now have too-high zinc content; not legal or efficient to use on cpvc or pex tube (saddle tee valve no reinforement internal for pex tube and "clamp" will crush cpvc. Where are these generally used? on copper tube, and as explained there are easy, quick, cost effective, legal, efficient, and long lasting alternatives to installing a tee valve that don't include soldering or brazing with copper tube, or drill tapping existing galvanized potable distribution.

    Now, all that having been said, and the fact I didn't say they were illegal to install EVERYWHERE, but did give an opinion as to their worthiness in general.

    I disagree with your statement that they are legal everywhere, that they can be used everywhere in the three or so locations you claimed. I further disagree with your premiss/hypothosis that because you find them availble to purchase means that an item is legal and code compliant to install for a particular use or purpose.

    I further would like your references to Utah Plumbing Code, Mechanical Code and Residential Code backing up your statement as pertains to Utah, and a reference for an accepted, approved, or certified saddle tee valve for other than lead content.

    Thank you in advance for your prompt reply.

    Last edited by H.G. Watson, Sr.; 10-15-2010 at 11:41 AM.

  14. #14
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    Default Re: Anyone have experience with these?

    The National Standard Plumbing Code-

    Section 10.12.4 Valves in dwelling units

    e. Self-piercing and needle-type saddle valves shall be prohibited.

    Last edited by Darren Miller; 10-15-2010 at 03:23 PM.
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  15. #15
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    Default Re: Anyone have experience with these?

    Mr. Watson,

    In reference to your post:
    1. huh?
    2. Section 609 of the IPC deals specifically with Health Care Plumbing, as in Hospital. If you see an evaporative humidifier installed in a hospital I would flag it.
    3. huh?
    4. New saddle valves are made of brass, the same as your kitchen faucet.
    5. Any valve is subject to failure.
    6. ok, self tapping should not be used on galvanized.


    I don't recall saying in my post that they are legal everywhere, you missed the point. The truth is I have a day job and don't have time for dissertations on the legal, moral or effective use of tap valves.

    Darren,

    I am afraid I am not familiar with the National Standard Plumbing Code, most of my work deals with the IPC. If that's what the NPC staes then you certainly wouldn't want to use needle valves where that code is enforced.

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  16. #16
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    Default Re: Anyone have experience with these?

    Quote Originally Posted by Rod Butler View Post
    Mr. Watson,

    In reference to your post:
    1. huh?
    2. Section 609 of the IPC deals specifically with Health Care Plumbing, as in Hospital. If you see an evaporative humidifier installed in a hospital I would flag it.
    3. huh?
    4. New saddle valves are made of brass, the same as your kitchen faucet.
    5. Any valve is subject to failure.
    6. ok, self tapping should not be used on galvanized.
    1. Speaks for itself, and is accurate. Utah specifically incorporates IPC into its verson of the IRC. Too bad you don't know the history of model codes adoption for your state, or that before Utah adopted the I-Codes they based upon another Model Code set, that's why Utah still refers to its legislation as "Uniform".

    2. I had given the correct citation intially BEFORE you joined this topic discussion. Only when responding to your outrageous all encompasing statements that saddle tee valves were legal because they were available for sale at Lowes and Home Depot, I made a transposition and typed 609.5, in the post directed to you. It was a simple typo. If you had the code out or bothered to read the thread you were posting on you would have known that.

    IPC, chapter 6, Section 605.9 number 4.

    Section 605.9 is NOT limited to Health care occupancies. It is specific, in that it expressly prohibits saddle valves, and pertains to all occupancies, and expressly prohibits saddle valves. Utah, the IRC having incorporated the IPC would apply, UNLESS Utah has ammended Section 605.9.

    3. You're the one that made the argument that if it was available for sale in the store it was legal to install, Huh! Yourself.

    4. Too funny. Glad you think so, you're not correct in your assumptions, there are multiple forumlae for brass by the way, and not all saddle tee valves are the same.

    5. Apparently you are ignorant of the prospects of legionaire's disease, and the whys and how's of such a contamination chain of events; why a misting/spray type humidifier with pad and tray (the TOPIC OF THIS THREAD) via a saddle tee valve would be a concern.

    Try looking up the citation 605.9, see number 4.

    As far as your "day job" I couldn't care less.

    Last edited by H.G. Watson, Sr.; 10-15-2010 at 08:28 PM.

  17. #17
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    Default Re: Anyone have experience with these?

    Quote Originally Posted by Rod Butler View Post
    Mr. Watson,
    2. Section 609 of the IPC deals specifically with Health Care Plumbing, as in Hospital. If you see an evaporative humidifier installed in a hospital I would flag it.
    Quote Originally Posted by H.G. Watson, Sr. View Post
    I made a transposition and typed 609.5, in the post directed to you. It was a simple typo. If you had the code out or bothered to read the thread you were posting on you would have known that.

    IPC, chapter 6, Section 605.9 number 4.

    Section 605.9 is NOT limited to Health care occupancies.

    So, let me get this straight, H. G. made a typo, Rod did not know that H. G. made a typo and took it as H. G. knew what he was typing, so, instead of H. G. saying that he made a mistake he blames the error on Rod for not guessing and figuring out that H. G. made a mistake?

    Huh? H. G., next time simply state that you made a typo and that you meant blah, blah, and blah, and don't blame someone else for not figuring out that you made a mistake. Sheesh!

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  18. #18
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    Default Re: Anyone have experience with these?

    FWIW saddle valves are prohibited by the IL State Plumbing Code. And with good reason, many that I find are leaking.

    Michael Thomas
    Paragon Property Services Inc., Chicago IL
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  19. #19
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    Default Re: Anyone have experience with these?

    Yes Illinois is yet another state who self-authors their plumbing code, and EXPRESSLY PROHIBITS saddle valves, saddle tee valves.

    Here is yet the "other" issue, where-in those plumbing codes that may not expressly prohibit saddle fittings as a joint or connection for distribution/supply, but still would prohibit, yet not expressly....the use for things such as seasonal equipment/not regularly open and flushing equipment, fixtures, etc. And why even IF such would be premitted to use for say Evap/swamp coolers, humidifiers, etc. why it is such a BAD idea.

    Such devices supplied by such needle valves are via a length of plumbing material. Usually copper tube (old school and required some limited skill to shorten to length and use a compression fitting end; easy to crimp, restrict or damage accidentially; and rarely, IF EVER done anymore; and if found, usually excessive and coiled length!), pex, "poly hose" or other. The usual reasons why such is employed in the first place often includes difficult accessibility and limited working space. At the "business" end of the tube you're connecting to a valve on the appliance/appartunance which is automatic (usually a backflow prevention of some sort, hopefully vacuum break and/or air gap as well....then we need to consider that ...

    Back up at the saddle tee it is OPEN and THE Usual sitution is that the homeowner/occupant LEAVES that saddle valve OPEN year-round never giving IT or the line to the device it is feeding a second thought, unless there is a leak or a stoppage. During the three, six, eight, or nine months that the supplied swamp cooler, mister, or humidifier IS NOT running, NOT opening its integral valve, NOT drawing water, not FLUSHING that supply line - that supply "line" from that saddle valve TO the valve on the device is full of stagnated water in the PLUMBING DEAD END. "Dead" for those three to ten MONTHS that the device IS NOT USED.

    We all know that just about NOBODY goes to CLOSE these valves every end of use season and DRAINS the line TO the cooler, mister, humidifier, automatic valve. Rarer still would be to then SANITIZE and FLUSH that line PRIOR to re-opening that saddle valve.

    If they DID - they'd soon have the needle valve/saddle valve FAIL to fully open or close, and the stress of having operated it causing the saddle to losen, and cause a leak, the tap area or gasket to leak, the packing nut to losen and leak, or the dang needle inlet to be CLOGGED.

    Plumbing "dead ends" and it (the appliance or appurtuance supply line "fed" by the saddle valve) technically IS one (a DEAD END) during those seasonal periods of NON-USE. We used to feel that since were most always used with copper tube to the device, the biocidic qualities of the copper would some how protect and make safe; experience proved not the case; further you never, or rarely see copper tube on the supplied side of such these days. You also find the USUAL is excessive length and coiled up LOOPS of material, rarely to length, and WITHOUT an intentionally fashioned drip loop (for when that not a matter of IF but WHEN overhead leaking saddle valve runs surface contamination over that air gap and into whatever pad, pan, etc. is below) and carries with surface tension it all the crap, dust, and whatever into same.

    Hence Georgia's ammended exception for 1-2 family residential only to permit ONLY for a refrigerator ice-maker - their justification being that if one has such - it will be used/flushed frequently and year-round; or it would not be installed in-the-first-place. They don't even provide an exception for an "insty-hot" water spigot at the kitchen sink, or a water filter system at the kitchen sink. Guess they feel no year-round use of instant hot water, insufficient flushing, and same for filtered water at the kitchen sink, Huh? Nope, you can look into the discussions that led to the limited exception, because under the sink, no excuse to not require proper joints and connections.

    I don't agree with their choice to allow even the selective ammendment exception allowing use for the refrigerator icemaker, but it wasn't "up to me".

    Last edited by H.G. Watson, Sr.; 10-16-2010 at 07:30 PM.

  20. #20
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    Default Re: Anyone have experience with these?

    Sears was recently sued here in IL by someone who had a saddle valve installed by a "contractor" working for Sears. Still in litigation, but it does appear that Sears has a problem.

    Bradly vs Sears

    Last edited by Michael Thomas; 08-05-2012 at 06:46 AM.
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  21. #21
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    Default Re: Anyone have experience with these?

    Humidifiers are alive and well and, in homes with a significant amount of woodwork, I recommend them in my reports – even in North Central Texas. From my report autotext (borrowed from the NPS Museum’s Curatorial Care of Wooden Objects).

    “The ideal relative humidity level in most areas of the country for wooden
    objects is 50% plus or minus 5%. In dry climates, such as the southwest,
    35% to 40% is acceptable. These levels are difficult to achieve in very dry
    climates because the moisture content in wood drops rapidly below 35%
    RH, causing splits. Below 30% the glue may desiccate, joints may loosen,
    and finishes will become brittle. Along the coast, 55% to 60% is
    acceptable, but above 70% mold and insects may become problems. When
    humidity is this high, glue may weaken, finishes may bloom, hardware will
    corrode, and wood fibers will swell excessively.

    Rapid changes in relative humidity, as mentioned earlier, may cause severe
    damage to furniture. An increase in RH from 30% to 70% can cause wood
    to expand as much as 2% across the grain. In this case a 2-foot panel could
    expand almost 1/2 inch causing splitting, veneer loss, and joint failure.
    Avoid temporarily heating, air conditioning, or humidifying spaces that house wooden objects. Do not turn off heat or air conditioning at night.”

    However, I do not inspect them. I specifically exclude them from my reports.

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