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  1. #1
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    Default Microwave oven testing?

    Is there a standardized method for testing a microwave oven for proper function?
    Or what do you do to ensure unit is functioning properly?

    The reason I ask is AHS is refusing another clients request for repairs.

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    badair http://www.adairinspection.com Garland, TX 75042 TREC # 4563
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  2. #2
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    Default Re: Microwave oven testing?

    Quote Originally Posted by BARRY ADAIR View Post
    -----------------------------------------Or what do you do to ensure unit is functioning properly?

    Barry,

    If and only if it's a built in.

    Crumpled up Wet paper towel. Starts to steam in about 30 to 45 seconds on high.

    It Might have Choked Artie But it ain't gone'a choke Stymie! Our Gang " The Pooch " (1932)
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  3. #3
    Nolan Kienitz's Avatar
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    Default Re: Microwave oven testing?

    Barry,

    I follow what I learned from a 20+ HI veteran in Houston:

    Timer & Clock: Functioning? Y/N (actually an additional item not required)
    MWave: Small glass of water, heat/run for 60 seconds, if water is boiling it is functional.
    Carousel: Turns? Y/N

    Then there are the Range Hood options, but that is a different section of the 7A-0 form, but I do refer one to the other.

    As noted above ... for built-in units only. I don't touch the portable units.


  4. #4
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    Default Re: Microwave oven testing?

    Barry, I don't know of a specific test, but the boiling water is mentioned in the TREC standards as an option.

    (f) Microwave oven. The inspector shall:

    (1) report as in need of repair any broken or missing knobs, handles, glass panels, or other parts, or a unit that is not securely mounted;

    (2) report as in need of repair any deficiencies in the door and seal (the inspector is not required to test for radiation);

    (3) report as in need of repair an oven that does not operate by heating a container of water or with other test equipment, as reasonably determined by the inspector; and
    My other test equipment is the multipurpose rag I carry in my pocket which exhibits an elevated temperature when heated for 10 seconds. My test equipment is faster and safer and can be used even if no water service is present. I tried using the boiling water thing when I first started out and got burned once.

    Jim Luttrall
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    Default Re: Microwave oven testing?

    I carried a microwaveable hard plastic drinking cup which I would fill with water, set the timer to 30 seconds, and if the water was not 'hot to the touch', it was 'not working'. Depending on how large or small a cup you use, the water will likely boil in less than 60 seconds - I found that with the size cup I used, 30 seconds would make it 'hot to the touch'.

    Jerry Peck, Construction / Litigation Consultant
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    Default Re: Microwave oven testing?

    I've always said a cup of tap water for 1 minute at high should be at least 120°F otherwise just wait for the sink supply in most homes.

    I also carry microwave popcorn and will pop a bag for function and snacking on vacant properties and will ask permission on occupied, when clients are around, they like the treat and proof their future micro is working.

    The issue on this one instance is a $900.00 unit that requires repair or replacement IMO and the warranty co. does not want to honor their agreement, go figure.

    I was just curious what test methods were used by others.

    Warranty co. says, "Inspector's 1 minute test along with a light tester is inferior and should be tested on high for 2 1/2 minutes this should boil water 212°F in most units."
    Unit in question will only get to 200°F by their own time and test,
    "but that is close enough" they say.

    Glad I don't have to eat their cooking

    Found this wattage formula but doubt it's any better than what I/we try to do during an inspection How to Easily Test Your Microwave Oven's Wattage

    I'm with Jim on the boiling thing, injury or too messy on previous occasions

    I'll be sticking to the 1 minute and light tester or popcorn until shown different

    HNY BTW and thanks for your replies

    badair http://www.adairinspection.com Garland, TX 75042 TREC # 4563
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  7. #7
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    Default Re: Microwave oven testing?

    Barry,

    I also do the test with a cup. I use the regulation sized sippy cup, nothing fancy.

    Fill the small cup and turn on for 1 minute. If water is hot to touch, I note on report that a cup of water was heated after 1 minute test.

    I also check to make sure the turntable is operable and that the unit is properly supported. Check to make sure there is no damages to the door or the glass panel.

    Another thing I do is make sure that the recirculating fan is venting properly. Many of these have had to fan cover panel removed as if they are going to be vented to the exterior; but many I have found vent to the bottom of the above cabinet.

    I also make note if the bottom surface light is not operable and the condition of the filters.

    rick


  8. #8
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    Default Re: Microwave oven testing?

    I guess it goes without saying to check the receptacle the microwave is plugged into - I have found quite a few that are improperly wired, when the rest of the receptacles in the kitchen were ok.

    Last edited by John Arnold; 01-01-2008 at 08:00 AM. Reason: editing

  9. #9
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    Default Re: Microwave oven testing?

    I use the wet paper towel method. Wet the paper towel put it in the center and turn the unit on for about 15 seconds. That is all it takes for a nice steaming paper towel.

    In my report I tell how I tested the microwave and that the only thing I can tell them is that it worked well enough to make the paper towel steam. I write in the report that I did not cook anything in it to test it.

    Scott Patterson, ACI
    Spring Hill, TN
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  10. #10
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    Default Re: Microwave oven testing?

    Quote Originally Posted by BARRY ADAIR View Post
    Warranty co. says, "Inspector's 1 minute test along with a light tester is inferior and should be tested on high for 2 1/2 minutes this should boil water 212°F in most units."
    Unit in question will only get to 200°F by their own time and test,
    "but that is close enough" they say.
    Their 'standard' is likely for their 'new' units. That may be how they selectively test their units heating capability off the assembly line. Not real scientific like the QA tests I did at a defense plant I worked at for 5 years after high school, but, then, this is not trying to guide airplanes at 500 mph at 50 above the ground either . Their test will demonstrate that the 'unit is working to their specification', presuming that is representative of their specification, of course.

    Now, to the link you provided:
    "Keep in mind that it’s normal for a microwave to produce less energy as it ages (hmmm… sounds familiar somehow!), but your results should be within about 50-75 watts of the rating."

    I'd guess that the 12 degrees difference is within or close to that "50-75 watts of the rating".

    By the way, the stuff I worked on was with microwaves, only very few of our tubes were in that low wattage range. We even had a few in the <1 watt (rated in mW) range, but most were in the kW to MW range (some I tested were over 5 mega watts). Nonetheless, though, there is a reduction in power over time (aging effect) as stated in your link.

    Jerry Peck, Construction / Litigation Consultant
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  11. #11
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    Default Re: Microwave oven testing?

    Warranty co. says, "Inspector's 1 minute test along with a light tester is inferior and should be tested on high for 2 1/2 minutes this should boil water 212&#176;F in most units."
    Unit in question will only get to 200&#176;F by their own time and test,
    "but that is close enough" they say.
    Notice there is no reference to the starting temperature?
    That would also be something to consider when testing to a specific temperature over a certain time; 40 degree water takes longer to reach boiling than 80 degree water.

    Jim Luttrall
    www.MrInspector.net
    Dallas, Texas

  12. #12
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    Default Re: Microwave oven testing?

    Quote Originally Posted by BARRY ADAIR View Post
    ... Warranty co. says, "Inspector's 1 minute test along with a light tester is inferior and should be tested on high for 2 1/2 minutes this should boil water 212°F in most units." ...
    Does, did or will the warranty company provide documentation for their testing procedures? It would be nice to see what that basis is.

    I don't think any of the various SOPs get to this level of data collection for a microwave.

    I know that isn't the bottom line here as you are working with a client to help resolve an issue and are being taken to task for more definitive information.


  13. #13
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    Default Re: Microwave oven testing?

    I basically do all the same as stated above:

    check seal
    turntable
    light
    temp w/ sippy cup of agui for 1x min-- s/b 110-120F
    CHECK FOR RUST!!! Any rust is necessitates hitting it with a baseball bat.

    I do not check units not permanent to the structure (built-in).

    Dick


  14. #14
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    Default Re: Microwave oven testing?

    I use the paper towel method too.

    NOTE!! Do NOT put a "dry" fabric shop towel in for the test. It WILL catch fire - yes flames and a lot of nasty smelling smoke. Not that it ever happened to me....no, and that's my story.

    I check the control panel to see if the buttons work.
    The light and turntable.
    If it heats up my paper towel to steam.

    "Inspector's 1 minute test along with a light tester is inferior and should be tested on high for 2 1/2 minutes this should boil water 212°F in most units."
    Unit in question will only get to 200°F by their own time and test,
    "but that is close enough" they say."

    They may have a point. The cheapo microwave in my basement takes much longer to make popcorn compared to the one in the kitchen. I think the power rating has a lot to do with it. If it boils water in a reasonable amount of time, I would have to say it is probably OK.

    When I make press coffee (in the good kitchen one), I put 16 oz of water (room temp) and hit 3 minutes and it boils just before the timer goes off. And it's a full rolling boil by then (220 degrees).

    I have found that if I use the water from my refrigerator door, it just about the same time.
    JF


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    Default Re: Microwave oven testing?

    Why any paper towel at all? Why put anything combustible at all in a micowave? Show me the light.

    rick


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    Default Re: Microwave oven testing?

    Quote Originally Posted by Rick Hurst View Post
    Why any paper towel at all? Why put anything combustible at all in a micowave? Show me the light.

    rick
    Rick,


    It's wet not damp. Most always on site. one less thing in the bag.

    Push 33 start it steams that part of testing is done.(Don't Walk away).

    1.Dish Washer

    2.Set Oven 350

    3. Set Burners on Low

    Snatch a couple of paper towels (wet and leave water running.)

    Press 33 start.(Light comes on?,Table turning?

    Open cabinet under sink (Drain Leaking?)

    Microwave timer dings. Steam = Microwave,Seal?Cabinet?Test other Buttons,

    Back to Drain. ect.

    Everybody has their own way.

    It Might have Choked Artie But it ain't gone'a choke Stymie! Our Gang " The Pooch " (1932)
    Billy J. Stephens HI Service Memphis TN.

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    Default Re: Microwave oven testing?

    Quote Originally Posted by Jack Feldmann View Post
    And it's a full rolling boil by then (220 degrees).
    220 degrees F?

    I've always thought, and been told, that water boils at 212 degrees, and that boiling water never gets hotter than 212 degrees F - it just boils faster and faster and faster the more heat you add, but the temperature does not rise.

    Jerry Peck, Construction / Litigation Consultant
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  18. #18
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    Default Re: Microwave oven testing?

    Quote Originally Posted by Jerry Peck View Post
    220 degrees F?

    I've always thought, and been told, that water boils at 212 degrees, and that boiling water never gets hotter than 212 degrees F - it just boils faster and faster and faster the more heat you add, but the temperature does not rise.
    Generally speaking: the temperature at which boiling occurs (boiling point) depends upon pressure. At sea level (14.7 psia or 0 psig), yes water boils at 212 degrees. On a mountain in Colorado it will boil at a lower temperature. A lot of cook books have "high altitude" instructions to adjust recipes for this lower boiling temperature. Water will boil at higher temperatures when under pressure (hence the use of the "pressure cooker") and on a submarine (I believe they do allow the air pressure to increase somewhat above normal atmospheric when submerged).

    When it begins boiling, liquid water will continue to boil at the same temperature (dictated by the pressure). As more heat is applied the rate of boiling increases but the temperature remains the same. The steam will be at a much higher temperature than the boiling water.

    However there is also a special case called superheating. A liquid can be heated to a temperature significantly above it's normal boiling point if it is heated in a smooth walled container and kept very still. This prevents those little bubbles from forming in the water (called nucleation) and delays the onset of boiling. When being superheated, the water is storing energy that will be released in a steam explosion accompanied with rapid boiling if the water is disturbed.

    Superheating is a concern when using microwave ovens to boil water, especially those units without turntables. Opening the door, setting the cup down on the counter, dropping a tea bag or a spoon of sugar into it ... any of these could kick off the boiling process and send scalding water flying. Many people have gotten severe burns from this.


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    Default Re: Microwave oven testing?

    Quote Originally Posted by Brandon Chew View Post
    Generally speaking: the temperature at which boiling occurs (boiling point) depends upon pressure. At sea level (14.7 psia or 0 psig), yes water boils at 212 degrees.
    Yes, I was referencing the sea level boiling point as Jack stated 212 degrees.

    Water will boil at higher temperatures when under pressure (hence the use of the "pressure cooker") ...
    Correct, but an open pot is not under pressure. I may have erred when I "assumed" Jack was referencing an "open pot".

    When it begins boiling, liquid water will continue to boil at the same temperature (dictated by the pressure). As more heat is applied the rate of boiling increases but the temperature remains the same. The steam will be at a much higher temperature than the boiling water.
    Okay, that is what I was referring to.

    However there is also a special case called superheating. A liquid can be heated to a temperature significantly above it's normal boiling point if it is heated in a smooth walled container and kept very still. This prevents those little bubbles from forming in the water (called nucleation) and delays the onset of boiling. When being superheated, the water is storing energy that will be released in a steam explosion accompanied with rapid boiling if the water is disturbed.

    Superheating is a concern when using microwave ovens to boil water, especially those units without turntables. Opening the door, setting the cup down on the counter, dropping a tea bag or a spoon of sugar into it ... any of these could kick off the boiling process and send scalding water flying. Many people have gotten severe burns from this.
    Thank you, learned something new today. I had heard of "superheating" but never in reference to something like that.

    Last edited by Jerry Peck; 01-03-2008 at 05:29 PM. Reason: had 121 instead of 212 degrees
    Jerry Peck, Construction / Litigation Consultant
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    Default Re: Microwave oven testing?

    At a home the other day, when I opened the microwave there was already a cup of water in the unit.

    I asked the homeowner if she was going to warm it up for coffee. She told me no that it was there to catch the micowave "thingies".

    After the WTF look I gave her, she told me that she had been told by a lab professor years ago that the water help catch any of the bouncing microwaves still left in the oven when it was turned off.

    She said she had been doing this for about 25 years now.

    This also explained why the tennis balls where hanging down from the ceiling in the garage.

    rick


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    Default Re: Microwave oven testing?

    Sorry Jerry - hit the wrong keys. I know that's never happened here before.


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    Default Re: Microwave oven testing?

    Quote Originally Posted by Jack Feldmann View Post
    Sorry Jerry - hit the wrong keys. I know that's never happened here before.


    You mean like I just had to go back and edit mine and show the reason for editing as: "had 121 instead of 212"



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  23. #23
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    Default Re: Microwave oven testing?

    The scientific data has came in.

    rick

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    Default Re: Microwave oven testing?

    Quote Originally Posted by Rick Hurst View Post
    The scientific data has came in.

    rick
    What was the starting temp?


  25. #25
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    Default Re: Microwave oven testing?

    Quote Originally Posted by Rick Hurst View Post
    ... This also explained why the tennis balls where hanging down from the ceiling in the garage. rick

    Rick,

    I thought they are the start of stalactites in the garage caves

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  26. #26
    William Zoller's Avatar
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    Question Re: Microwave oven testing?

    One more thought on this subject: It's been rumored that superheated water in a microwave environment can actually rise above the boiling point without visibly boiling. When removing container from the interior, it may feel cool to the touch, but the water then explodes when disturbed.

    I have not personally experienced this, but have found some validity to this claim while searching the internet.

    Just something of which to be aware.


  27. #27
    Ted Menelly's Avatar
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    Default Re: Microwave oven testing?

    Quote Originally Posted by William Zoller View Post
    One more thought on this subject: It's been rumored that superheated water in a microwave environment can actually rise above the boiling point without visibly boiling. When removing container from the interior, it may feel cool to the touch, but the water then explodes when disturbed.

    I have not personally experienced this, but have found some validity to this claim while searching the internet.

    Just something of which to be aware.

    I have grabbed many an iterm from microwaves and at first grab they are not hot at all and by the time you get to the counter your fingers are frying.

    Only in the microwave. Things on stoves or in ovens are just blister material. You don't have to wait to feel the heat.


  28. #28
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    Default Re: Microwave oven testing?

    Quote Originally Posted by William Zoller View Post
    One more thought on this subject: It's been rumored that superheated water in a microwave environment can actually rise above the boiling point without visibly boiling. When removing container from the interior, it may feel cool to the touch, but the water then explodes when disturbed.

    I have not personally experienced this, but have found some validity to this claim while searching the internet.

    Just something of which to be aware.
    Quote Originally Posted by Ted Menelly View Post
    I have grabbed many an iterm from microwaves and at first grab they are not hot at all and by the time you get to the counter your fingers are frying.

    Only in the microwave. Things on stoves or in ovens are just blister material. You don't have to wait to feel the heat.
    That's because, in a regular oven, the container is heated first, then the heat works its way through to the stuff in the container, while in a microwave oven the stuff in the container heats first, then the heat works it way through to the container.

    With a microwave oven you are standing there waiting for the seconds to tick off so you can take out whatever you were trying to heat in a hurry, and you pick the container up with limited heating of it, but by the time you get it to the counter - Yikes! I should have used a pot holder! - nothing mysterious about that.

    Regarding the water boiling thing? I seriously doubt it as the difference would be pressure, not heat, and the inside of the microwave is essentially at the same air pressure as the outside-the-microwave air pressure is. However, if you heated the water to just-below-boiling, opened the door and reached for it, the residual heat of the moment before could now have caused the water to reach boiling, but it is not going to explode when disturbed. I think it would be related to the heating of the container - if the container is not yet hot, it will not boil as heat is being lost to the container, however, if at that precise moment in time the container heated, then the last heat applied would be held in the container and would finish heating the water to boiling, but again, not exploding when disturbed.

    It would take some convincing arguments and data to make my believe that happens.

    Jerry Peck, Construction / Litigation Consultant
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  29. #29
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    Default Re: Microwave oven testing?

    This is from a user manual for GE Microwave:

    SUPERHEATED WATER
    Liquids, such as water,
    coffee or tea are able to be
    overheated beyond the
    boiling point without
    appearing to be boiling.
    Visible bubbling or boiling
    when the container is
    removed from the microwave
    oven is not always present.
    THIS COULD RESULT IN VERY
    HOT LIQUIDS SUDDENLY
    BOILING OVER WHEN THE
    CONTAINER IS DISTURBED
    OR A SPOON OR OTHER
    UTENSIL IS INSERTED INTO
    THE LIQUID.
    To reduce the risk of injury
    to persons:
    — Do not overheat the liquid.
    — Stir the liquid both before
    and halfway through
    heating it.
    — Do not use straight-sided
    containers with narrow
    necks.
    — After heating, allow the
    container to stand in the
    microwave oven for a short
    time before removing the
    container.
    — Use extreme care when
    inserting a spoon or other

    utensil into the container.
    Superheated Water In Microwave Can Explode - Email Warning
    try this Jerry (no, no, Don't TRY this) just see if this from GE persuades you.
    snopes.com: Superheated Microwaved Water
    Or this from Snopes
    Here is a brief explanation:
    As well as heating up everything from breakfast noodles to nightcaps, each of these tens of millions of microwave ovens can "superheat" a cup of water, and if you are very unlucky, toss it into your face.
    You would expect that "boiling point" is straight-forward — it's the temperature at which a liquid boils and turns into a gas.
    But "superheating" is a strange phenomenon in which a liquid can be heated to above its boiling point. For example, water can be heated to 101&#176;C, and still remain a liquid and not turn into steam.
    Liquid water will become steam at 100&#176;C, if there already is a tiny bubble of anything (air, steam) present. But if there is no such bubble present, then the liquid will need to be heated to over 100&#176;C to get enough energy to make that first bubble.
    A typical disaster scenario has the unwitting person first filling a cup with water — a cup with a very smooth internal surface.
    A surface with tiny scratches has a myriad of hiding spots for bubbles, but a smooth surface does not. They place this very smooth bubble-free cup into their nuker, which heats the water to 101&#176;C.
    This superheated water is like a cocked gun, needing only a small "trigger" to set it off. The trigger can be the addition of a tea bag, instant coffee powder or sugar, each of which will carry bubbles into the superheated water.
    The trigger can even be the shock wave from moving or bumping the cup of superheated water.
    Your typical cup of tea has a volume of about 100ml, roughly the volume of a tennis ball. In your typical 100ml of superheated water in a cup, 0.2ml (about the volume of a big match head) will turn into 300ml of steam.
    If that "match head" of water is on the surface, it will turn into a small puff of steam. But if that 0.2ml volume of water is near the bottom of the cup, it will push all the water above it out of the cup.
    If you happen to be bending closely over the cup, you can get a faceful of hot water.
    It's easy to avoid. Don't heat the water in your microwave for too long. Use an old cup with a few scratches. Have a non-metal object, like a wooden spoon or a stirring stick, sitting in the heating liquid — its furry surface will trap lots of bubbles.
    Before you remove the cup from the nuker, tap its side from a safe distance with a long object. And as always with hot water, keep your face and body at a safe distance.


    Last edited by Jim Luttrall; 04-06-2009 at 10:38 AM.
    Jim Luttrall
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  30. #30
    A.D. Miller's Avatar
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    Default Re: Microwave oven testing?

    Quote Originally Posted by Jerry Peck View Post
    220 degrees F?

    I've always thought, and been told, that water boils at 212 degrees, and that boiling water never gets hotter than 212 degrees F - it just boils faster and faster and faster the more heat you add, but the temperature does not rise.
    JP: Everything takes a little longer in Tennessee.


  31. #31
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    Default Re: Microwave oven testing?

    Quote Originally Posted by Jim Luttrall View Post
    Superheated Water In Microwave Can Explode - Email Warning
    try this Jerry (no, no, Don't TRY this) just see if this from GE persuades you.
    snopes.com: Superheated Microwaved Water
    Or this from Snopes
    Here is a brief explanation:
    Yep. I heat water in the micro wave every morning. Pull it out, heat the fingers a little, put the coffee in and watch it come to a roaring bubble for an instant.

    I had that info on my computer once and now I do again.

    Thanks Jim


  32. #32
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    Default Re: Microwave oven testing?

    I use a cheap red plastic cup half filled with water, set it on high for 3 minutes and let it rip. When it's finished I open the door and point my IR thermometer at it and record the temperature. I leave the cup in the oven so as not to get burned.


  33. #33
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    Default Re: Microwave oven testing?

    Quote Originally Posted by Jerry Peck View Post
    It would take some convincing arguments and data to make my believe that happens.
    Quote Originally Posted by Jim Luttrall View Post
    This is from a user manual for GE Microwave:
    Jim,

    Okay, I'm taking that as a "convincing argument".

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  34. #34
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    Jul 2008
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    Snowbird (this means I'm retired and migrate between locations), FL/MI
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    4,086

    Default Re: Microwave oven testing?

    I've always used one cup of measured tap water in a vintage two-cup Pyrex (R) measuring cup.

    Plastics can melt. Too much plastic and decorated items from overseas contain metals, especially lead, remember the recalls and even pvc blinds from china and mexico.

    I have always used this method. Otherwise avoiding trouble from home owners or purchasers with issues about "contaminating" their microwave and/or home with plastic fumes, lead, other toxins and avoiding the melted plastic rupturing, somthing else breaking, and flooding installed microwave or microhood.

    Note: I've heard that modern Pyrex (R) is reformulated, not made here anymore, and not as chip resistant/strong as the vintage but haven't looked into that to verify, so it might not be the case.


  35. #35
    Ted Menelly's Avatar
    Ted Menelly Guest

    Default Re: Microwave oven testing?

    Quote Originally Posted by H.G. Watson, Sr. View Post
    I've always used one cup of measured tap water in a vintage two-cup Pyrex (R) measuring cup.

    Plastics can melt. Too much plastic and decorated items from overseas contain metals, especially lead, remember the recalls and even pvc blinds from china and mexico.

    I have always used this method. Otherwise avoiding trouble from home owners or purchasers with issues about "contaminating" their microwave and/or home with plastic fumes, lead, other toxins and avoiding the melted plastic rupturing, somthing else breaking, and flooding installed microwave or microhood.

    Note: I've heard that modern Pyrex (R) is reformulated, not made here anymore, and not as chip resistant/strong as the vintage but haven't looked into that to verify, so it might not be the case.
    All Pyrex or subtance as such is slowly leaving the US and going over seas.
    You can buy a coated 16 inch newtonian telescope mirror from over seas (and a pretty darn goon one) for 12 to 1500. In the US the price is anywhere from 2800 to 4000. The 2800 is probably to cheap a quote.

    Machine manufacturing and testing and coating and shipping from overseas is half or less the cost. Again this is for a fairly high quality mirror. Pyrex blanks for mirrors are almost impossible to get in the states for any size of 16 inches or over.


  36. #36
    Join Date
    Mar 2007
    Location
    Spring Hill (Nashville), TN
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    Default Re: Microwave oven testing?

    I find that the hamster "pop" method works the best. If the hamster pops within 20 seconds of the unit being on high then the oven is working!

    Seriously, I use a wet paper towel. If it steams in about 15 seconds then I say it is working. I also have one of those fancy plastic bars with LED lights that flash as the magnetron tube turns on and off. It is a good toy that the clients love to see and Oooh and Ahhhh over.

    Scott Patterson, ACI
    Spring Hill, TN
    www.traceinspections.com

  37. #37
    Ted Menelly's Avatar
    Ted Menelly Guest

    Default Re: Microwave oven testing?

    Quote Originally Posted by Scott Patterson View Post
    I find that the hamster "pop" method works the best. If the hamster pops within 20 seconds of the unit being on high then the oven is working!

    Seriously, I use a wet paper towel. If it steams in about 15 seconds then I say it is working. I also have one of those fancy plastic bars with LED lights that flash as the magnetron tube turns on and off. It is a good toy that the clients love to see and Oooh and Ahhhh over.

    I also have a leak detector. Some folks don't believe in them but I believe it works.


  38. #38
    Join Date
    Mar 2007
    Location
    Chicago, IL
    Posts
    10

    Default Re: Microwave oven testing?

    I used to use a leagage detector until it broke. The problem was there was noy way to determine what exactly a "high" indication meant and by who's standards. Go Figure.


  39. #39
    Ted Menelly's Avatar
    Ted Menelly Guest

    Default Re: Microwave oven testing?

    Quote Originally Posted by Larry Coha View Post
    I used to use a leagage detector until it broke. The problem was there was noy way to determine what exactly a "high" indication meant and by who's standards. Go Figure.
    The way I look at it is any of those cute little micro waves sneeking out and frying brains is too high a reading. Usually just pushing hard on the door and sealing it better shut the detector off.


  40. #40
    Daniel Leung's Avatar
    Daniel Leung Guest

    Default Re: Microwave oven testing?

    Quote Originally Posted by Larry Coha View Post
    I used to use a leagage detector until it broke.
    I use a "UEI" Model MW1A radiation leak tester too. (It is about $50 each. I have a working tester, and keep a brand new in my trunk in case for calibration.)

    I put in a plastic cup of tap water, set at high power level for 1/2 minute. Check any radiation leak along seam of oven door when it is in operation. Then check the cup is hot/warm or not. (I don't measure the temperature of the heated water, because it depends on the maximum output of oven.)

    Then I report, Operational microwave oven, no significant microwave leaking as tested by a "UEI" leak tester Model MW1A.


  41. #41
    A.D. Miller's Avatar
    A.D. Miller Guest

    Default Re: Microwave oven testing?

    You might try telling agents and sellers (maybe even cloying buyers) to look for the microwave leakage themselves. This will quell the depression they are experiencing due to having been pried away from reality TV long enough to try to delve into the mystery of why you are not being interrupted by commercials.

    Put the proverbial (preferably large) cup of water inside the oven; set the machine on high, and shut off the lights in the kitchen. Tell them it takes about 20 minutes or so for the leakage to appear as little, almost imperceptible red and blue sparks around the edges of the door.

    You can now go about your work undeterred.


  42. #42

    Default Re: Microwave oven testing?

    Good morning, Gents-

    I used to do a lot of microwave testing in homes, but nowadays, with microwave being so inexpensive, it is actually cheaper for someone to buy a new one than hire me to test their existing one.

    But just a quick point, contrary to what has been stated here on the board, there are emission standards and limits and there is a standard microwave testing protocol.

    You can find that located in the Code of Federal Regulations, Title 21 Part 1030

    Cheers!
    Caoimhín P. Connell
    Forensic Industrial Hygienist
    Forensic Industrial Hygiene

    (The opinions expressed here are exclusively my personal opinions and do not necessarily reflect my professional opinion, opinion of my employer, agency, peers, or professional affiliates. The above post is for information only and does not reflect professional advice and is not intended to supercede the professional advice of others.)

    AMDG


  43. #43
    Join Date
    Dec 2008
    Location
    Colorado
    Posts
    17

    Default Re: Microwave oven testing?

    Does anyone use the clearplastic microwave testers ?? Do they work??


  44. #44

    Default Re: Microwave oven testing?

    I'm not familiar with the device - could you provide a little more info on them?

    CPC


  45. #45
    Join Date
    Mar 2007
    Location
    Atlanta, Georgia
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    1,056

    Default Re: Microwave oven testing?

    "The Code is not a peak to reach but a foundation to build from."

  46. #46
    Ted Menelly's Avatar
    Ted Menelly Guest

    Default Re: Microwave oven testing?


    This is what I use

    MD200 Microwave Leakage Detector

    edit here

    Amazing how micro wave checking gets 2000 views and 50 replies. Just curious

    Last edited by Ted Menelly; 04-21-2009 at 01:36 PM.

  47. #47
    Join Date
    May 2007
    Location
    Tyler, TX
    Posts
    719

    Default Re: Microwave oven testing?

    Quote Originally Posted by Rick Hurst View Post
    At a home the other day, when I opened the microwave there was already a cup of water in the unit.

    I asked the homeowner if she was going to warm it up for coffee. She told me no that it was there to catch the micowave "thingies".

    After the WTF look I gave her, she told me that she had been told by a lab professor years ago that the water help catch any of the bouncing microwaves still left in the oven when it was turned off.

    She said she had been doing this for about 25 years now.

    This also explained why the tennis balls where hanging down from the ceiling in the garage.

    rick
    rotflmho

    Bruce Thompson, Lic. #9199
    www.TylerHomeInspector.com
    Home Inspections in the Tyler and East Texas area

  48. #48

    Default Re: Microwave oven testing?

    Hi Gents –

    I have a confession. I have a bit of a mischievous streak. Over the years, I have given family members “explanations” of various things that are less than – well – accurate.

    For example our daughter, an otherwise intelligent lass, now pushing 22 years old, recently had her boyfriend over for dinner. Somehow the conversation turned to hardware and tools, and in particular levels. My daughter let slip a bit of knowledge gained from her old Dad many years ago that the bubble in a spirit level was actually a fish fart, and the best quality levels used goldfish farts, because they were more stable.

    I don’t know how we managed to keep the boyfriend from choking with laughter.

    My daughter is still making discoveries about some of my explanations on how the world operates.

    Cheers!
    Caoimhín P. Connell
    Forensic Industrial Hygienist
    Forensic Industrial Hygiene

    (The opinions expressed here are exclusively my personal opinions and do not necessarily reflect my professional opinion, opinion of my employer, agency, peers, or professional affiliates. The above post is for information only and does not reflect professional advice and is not intended to supercede the professional advice of others.)

    AMDG


  49. #49
    Ted Menelly's Avatar
    Ted Menelly Guest

    Default Re: Microwave oven testing?

    Quote Originally Posted by Caoimhín P. Connell View Post
    Hi Gents –

    I have a confession. I have a bit of a mischievous streak. Over the years, I have given family members “explanations” of various things that are less than – well – accurate.

    For example our daughter, an otherwise intelligent lass, now pushing 22 years old, recently had her boyfriend over for dinner. Somehow the conversation turned to hardware and tools, and in particular levels. My daughter let slip a bit of knowledge gained from her old Dad many years ago that the bubble in a spirit level was actually a fish fart, and the best quality levels used goldfish farts, because they were more stable.

    I don’t know how we managed to keep the boyfriend from choking with laughter.

    My daughter is still making discoveries about some of my explanations on how the world operates.

    Cheers!
    Caoimhín P. Connell
    Forensic Industrial Hygienist
    Forensic Industrial Hygiene

    (The opinions expressed here are exclusively my personal opinions and do not necessarily reflect my professional opinion, opinion of my employer, agency, peers, or professional affiliates. The above post is for information only and does not reflect professional advice and is not intended to supercede the professional advice of others.)

    AMDG

    I use to play that game a lot when my kids were little.

    One that struck me a several years ago when one of my daughters was in a conversation about presidents with some friends. When they were talking about interesting things about presidents my daughter comes out with President Johnsons wives son from a first marriage. They all told her that Johnsons wife was not married before. My daughter said to them " Why do you think they call her lady bird and has a son called Larry Bird the basket ball player.

    Needless to say they all busted out and put her into serious embarrassment because old dad just mentioned it out of the blue once when she was a young girl in elementary school and she just found out it was one of my complete bull comments. I used to say them so seriously she never had a reason not to believe me. What would kids do without pain in the ass dads.


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