Radon mitigation do it yourself

[CJDave]

[img]/forums/images/icons/tongue.gif[/img] Now, Pat; here is the next question: "What is an interstice? If you have an interstitial air handler, where do you go to find it? Basement? Roof? Parking garage? [img]/forums/images/icons/crazy.gif[/img]

[Pat]

Dave, I never heard of "magnahelic" or anything real similar. Manometers are like liquid type barometers but open at both ends and in a U shape not purely veritical. The "U" tube with a liquid in it will show the differential air pressure between what the two different ends are attached. If you fill it with colored water and put rulers beside the vertical parts you can read the difference in inches of water. Given the vapor pressure of mercury and our more enlightened concern for contamination, U tubes filled with mercury and open to the air we breathe are not as popular as they used to be.

In recent decades, sensor chips to measure either PSIG or absolute are readily available as well as sensitive, accurate, and repeatable. They are used in electronic pressure gages, altimeters and even bank vault intrusion detectors where a small positive pressure is maintained in a vault and the gauge will detect any reduction of the pressure such as opening the door or making a hole in the wall.

Pat

[Pat]

Dave, An interstice is a space between other things. In common usage it is the space between closely packed other things, thus the interstitial space in a lateral line comprises the space in the volume of the lateral line that is in between the pieces of gravel.

Sometimes the term is used in the plural to refer to the collective summation of the spaces between other things, i.e. interstices.

I am not familiar with the usage you query about and can only hazard a guess. I would guess that an interstitial fan is in between two other components of the overarching system as between two sub systems. I don't think the term in and of itself so far as its denotative meaning gives any reason to choose from among your choices of locations. If there is a use of interstice or interstices which in the jargon of a trade and therein has a connotative meaning which would disambiguate the location of the fan, I am blissfully unaware of it.

Pat

[CJDave]

[img]/forums/images/icons/tongue.gif[/img] I have worked on a few buildings which had a floor-between-floors; an interstice; which was full of machinery. Maintenance Mechanics like them because you have ceiling access to the first floor and floor access to the second floor. The ceiling height of the interstice was less than full, just high enough to walk through easily. [img]/forums/images/icons/tongue.gif[/img] I have a home-made manometer that I use for setting gas regulators and HVAC blower pressures; I use that blue windshied washer fluid in it. [img]/forums/images/icons/tongue.gif[/img] German submarines had something called a: "Pappenburg Column" which I THINK was used for precise indication at very shallow depths. Of course it would have to be valved off at any kind of deeper settings. [img]/forums/images/icons/tongue.gif[/img] I've always like lots and lots of instrumentation. Since I suffer from acute anosmia, and can't tell if something is out of whack by the way it stinks, I need gauges; lots and lots of gauges. [img]/forums/images/icons/crazy.gif[/img]

[Pat]

Dave said, " I need gauges; lots and lots of gauges. "

Gauges! Gauges? We don't need no stinkin' gauges!!!

I like gauges too, especially in addition to or instead of idiot lights in automotive and other applications. I think all turbo diesels should have a pyro so after a hard run you know when it is prudent to shut down and lose cooling oil flow to the turbo bearings.

Pat

[egon]

Now fellows; in places where gauges are important to producing a product they are backed up by visual and audible alarms. The "Idiot Light" does get your attention faster than one of them thar gauges that you forget to look at! [img]/forums/images/icons/grin.gif[/img] [img]/forums/images/icons/grin.gif[/img]

Egon [img]/forums/images/icons/grin.gif[/img]

[Pat]

Egon, I have no difficulty with idiot lights as an adjunct to a gauge but don't like them replacing gauges.

You can wait a long time for the idiot light to come on if the bulb is burned out.

I would prefer that idiot lights be built into the gauges so when they illuminate your eye is immediately drawn to the gauge. Then there needs be no words on the light, just a light.

A problem with an idiot light is that it is binary, either on or off (usually...trying to interpret a light that is lighting a little bit or flickers is a job best done by a gauge.)

With a gauge you can notice your oil pressure varying with temp, fill level, etc and be aware that it is starting to drop below normal. An idioit light can't give an advance warning. With a radiator temp gauge you can see as you are working the engine hard that the temp is getting a tad high and lighten up a bit or investigate the cause which in my tractor is weed and grass debris on the screens in front of the radiator.

An alternator light can tell you the output is really low or non existent (typically the light is a broken belt indicator) but it does not give any indication that things are deteriorating, just that they have failed. I'd rather get an early warning so I can do something about it before it is a crisis.

Likewise volt and amp meters.

I like filter minder gauges too. Although mine are mounted at the filter the cost to the manufacturer for putting a solid state pressure sensor on ALL filters and having the car's electronics poll them ad seriatum with an annunciator to let you know if any are out of limits AND the ability to manually scroll through the readings so you can see the back pressure on each filter and make an informed decision about filter replacement before it is a must do interruption.

Yes Egon, warning lights are a good thing but along with not in place of an appropriate gauge. Wouldn't you just love to have a tachometer that was just a light that came on when you exceeded the red line but otherwise had no indication of RPM?

Pat

[Bird]

</font><blockquote><font class="small">In reply to:</font><hr />
warning lights are a good thing but along with not in place of an appropriate gauge

[/ QUOTE ]

My sentiments exactly. [img]/forums/images/icons/tongue.gif[/img] I don't want a car or pickup without a tachometer, plus fuel, oil pressure, and temperature gauges. Then either an ammeter or voltmeter. There's a few more I'd like to have, but almost none of the manufacturers include them as standard equipment; i.e., things like transmission, differential, and exhaust temperatures.

And a couple of things many vehicles DO have, that I do not have, but wish I did, are outside ambient temperature and a good compass. [img]/forums/images/icons/frown.gif[/img]

[egon]

Pat, the idiot lights come in pairs[in case one burns out] with an audible alarm. They should be set up to alarm at low and high points giving you an operating range. They will surely get your attention faster than a gauge. [img]/forums/images/icons/grin.gif[/img] [img]/forums/images/icons/grin.gif[/img]

Of course you can't monitor with them. That's not what they are for. [img]/forums/images/icons/grin.gif[/img]

Next we could get into computer monitoring of sensing points! [img]/forums/images/icons/grin.gif[/img]

Egon [img]/forums/images/icons/grin.gif[/img]

[Pat]

Egon, I have no quibble with upper or lower limit warning lights or audible alarms. Lights and audible alarms which direct your attention to the appropriate gauge are a good thing. I believe the rest of us were talking about automotive applications and you were talking about some stationery industrial application.

There is a "barber pole" (zebra striped) section on an aircraft altimeter at the low end so it gets your attention when the needle gets there. There are stall warning noise makers, even stick shakers to get your attention. Especially in multi engine planes there are so many gauges that it is tough to read them all and keep up your scan, especially when flying by instruments so... sometimes the designers mount the gauges so that important values are when the needle is pointed at one of the cardinal directions (up, down, left, or right._Of course even in a B-52 (8 engines) a quick glance will show you if one of the gauges is different from its buddies. If one has greater fuel flow or higher EGT it stands out by being different from the rest. No, I never got to actually fly a B-52 but did get stick time in a good simulator for B-52 H. Lots of dials and things to monitor!

Lets see now... this button launches the GAM-77 cruise missile with atomic warhead and this one that looks a lot like it buzzes for coffee...

Pat