How Vacuum Desiccators Work
And other paranormal experiences
OK, I admit it sounds a little like
the beginning of a bad joke. A hearing aid wearer walks into a repair lab
and says, "My hearing aid quits after I wear it for awhile." The
technician takes the hearing aid, puts it into a funny looking chamber and
turns on a vacuum pump. After a couple of minutes the technician gives the
hearing aid back to the user and says, "Have a nice day." End of story –
HA HA HA.
Some kind of magic?
Seems like some hocus-pocus. How can putting an aid in a vacuum
chamber bring it back to life? Well, here is the theory: hearing aids can
accumulate condensation internally from being in a humid environment. And
I mean think about it, the hearing aid is stuck inside a 98.6 degree
moisture producing cave with very little ventilation. And some wearers
perspire more than others making their instruments even more susceptible
to this problem. Symptoms include cutting out, distortion, weak or no
sound. It can be a tricky diagnosis because it may not happen every day,
and it may not give the same symptom every time.
How does it work?
Vacuum desiccators work by sucking the air out of the chamber,
including the air inside the hearing aid. And since the moisture is
getting in through the air, you will be removing the moisture by removing
the air. Now if you suspect a hearing aid may have internal condensation,
it is important to get it under vacuum ASAP. This can help make a better
diagnosis because if you leave the hearing aid lying around for awhile, it
will dry out on its own and will most likely start working again. You and
your customer will then be left guessing as to what the problem may have
Now this is just a theory, but you know all the times you have sent a
defective unit back to the factory for repair, and they couldn’t find
anything wrong with it? Most likely it had internal condensation and by
the time it reached the factory it had dried out and was working fine.
Now that "Hg number becomes more important
If you remember, last month we revealed that mysterious and confusing
"Hg specification that vacuum pumps boast. Well, I stated that this was
not the only important spec when looking for a vacuum pump to clean
hearing aids. We talked about the amount of Flow a vacuum pump has, and
how important it is in moving air for hearing aid cleaning (You can read
that article here:
. Well, when using vacuum to dry instruments the "Hg number becomes much
more important. Now remember, we are trying to suck out as much air as
possible from the hearing aid, and to do this we need to reach the maximum
attainable "Hg reading we can. The more air we remove, the better the
chances of drying the hearing aid. Now, if your pump has a smaller Flow
spec it will take longer to reach max vacuum, but none-the-less the more
air removed the better the drying results.
Again, the customer loves you
Here we go again, talking about customer satisfaction. But think about
all those instruments that have been sent back for repair that didn’t need
it. And how many customers went without their hearing aids when they
didn’t have to. And the customer knowing that it isn’t the hearing aid
that is the problem, and how they can help keep it from happening. That is
all worth a great deal to you and your customer.
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Have you checked out our Factory
2nds? These are brand new pieces of equipment which have a cosmetic
imperfection or two, but work perfectly fine. Check out our
Factory 2nd page to learn more.