What types of equipment need regular cleaning and lubricating, how often, and
with what?  This discussion started in electronics, regarding turntables and
bicycles, see there for more info.

30 responses total.

The fan on a dehumidifier we found (which should be turned on soon to keep
the windows from sweating) is stuck.  What should be used to lubricate it?
(The other option is just to plug in a fan next to it).

My dehumidifier fan motor froze and while a touch of oil to the bearings
helped, it froze again - the bearings were just shot. I had to replace
the motor. 

Would a window fan motor work?  We have extra working ones.  Or could just
run the window fan next to the dehumidifer.  I presume by oil you mean sewing
machine oil, not 3-in-1 or Wessons (which is what some nice grad students
fixed my first $1 phonograph with).

Take the motor apart, extract the bearings, clean them and the shaft out with
a solvent, place the bearings in hot 10 W oil and then put them back in the
motor.  I did this to my parents dehumidifier, after using 3 in 1 on it, some
25 years ago and it's still running fine.  Any motor you can get in the
unit should be fine.

In something like that, "take the motor apart" may not be beyond me, but "put
the motor back together" definitely is.  <sigh>

I found that the bearings in my motor were in enclosures that were spot welded
in place. There was no access without serious machining to replace and
align bearings. A new motor was the most economical option.

To digress way back to #1: Sindi, I'm curious.  This time of year most houses
are very dry - not in need of a dehumidifier.  Windows may sweat a little in
spite of the low humidity, but should not do so excessively if they have
adequate storms (or are well enough constructed).  (Besides which,
dehumidifiers are apt to ice up if the ambient temp is not somewhat warm, in
my experience.)  Or am I missing something really basic here?

I use a dehumidifier only in the basement - at the same time the furnace
humidifier is running, in fact. This is because I keep a library in the
basement and even low humidity but high relative humidity is bad for
books.  The dehumidifier never condenses liquid water - it forms ice, year
around.  However I have a timer that turns the power on and off at
intervals such that all the ice that forms while it is running will melt
while it is off.  It also has a humidistat, so it does not run at all if
the realtive humidity happens to be low enough. 

Sounds like the fan isn't drawing enough air through the evaporator if
it's icing up like that, Rane.

Its a well known effect for standard home dehumidifiers. The basement is
usually at about 65 F and the owners manual says "When the temperature
is lowered to approximately 65 F, frost build-up may begin to form on the
coil, at which time the continued operation of the unit is a waste of
electricity. The dehumidifier should be turned off until the frost has
disappeared." The problem is more that the coil area is undersized for
the refrigeration capacity of the compressor/evaporator. Actually, it is
not a waste of electricity as the ice continues to condense (and freeze)
moisture - and the area for doing so even increases! But it does have to
be turned off to melt and remove the condensed water. I should wire it
so that the fan continues to blow, which would both melt the ice faster
and condense even more water while doing so. 

We are planning to dehumidify a house under construction which has only single
glazing at the moment.  THe house is currently outdoor temperature, and the
windows are fine, but if we attempt to heat it (by opening windows to the
plasticked sunporches on sunny days) it goes up to 60 and the heated air
absorbs more moisture and at night it condenses out onto the glass and also
into the insulation (vapor barrier cannot be sealed until we replace some of
the subflooring).  So we have the option of working at outside temperature
for one more winter, or dehumidifying and heating to 50 while shining a heater
on the coils so they do not ice up.  Some combination of heater, box fan, and
dehumidifier may work to keep the whole house a dry 50, we hope.  Maybe one
setup on each floor.  We will eventually add a second set of double-glazed
low-E windows, and in the meantime some plastic, but we have to cut and screw
on some furring strips to attach the plastic to, and first we have to finish
work on the sublfloor (which rotted in places, along with some of the
underlying structure, in the few years before the roof went on).
        I recall one winter living in an apartment in an 1840s house, where
we had added two layers of plastic to each already-stormed window, when it
was below zero F for over a week and we had ice buildup on the walls but not
the windows.  Windows were R-4, walls had only drywall and wood sheathing and
siding (we plugged a few holes in it) under asphalt, R-3?  In this case the
walls are around R-38 and the windows R-1.  The ones leading onto the porch
(R-2) do not condense.

Don't use heat. Set a fan to blow on the evaporator coil. This might
prevent icing but even if it doesn't the ice will melt faster when the
dehumidifier is off (use a timer to turn it on and off). Dehumidification
will also be occurring while the ice melts. By the way, this will not, on
the average, cool the room.  When a dehumidifier is running the evaporator
coils are dehumidifying (or even making ice) but the condenser is right
behind the coils, and they are giving off the heat removed from the
evaporator. The air comes out of a dehumidifier *warmer* than it goes in,
by sum of the energies used by the compressor plus the energy released
when water was condensed (or frozen). It is overall heating the room much
in the fashion a heat-pump does.

We want to heat at the same time anyway, is there some problem with shining
a heat lamp on teh dehumidifier?  We also plan to move the freezer up out of
hte cellar into the bathroom area to add heat to the house (and keep the
freezer in a cooler space, the cellar is around 50 still).  Will freezers have
any problems at 45?
        Unfortunately we got stuck at Kiwanis and the dehumidifier has not yet
been looked at.  I may be trying winter camping tonight instead.  OR let the
windows puddle one more night.
        Silicone oil for copiers is what Jim fixed a turntable with yesterday
- it would not set down at 12", went to 7", there was too much friction
somewhere, shortening a spring would have fixed it too but he oiled it
insetad.  Anything wrong with copier oil?  It would also not autostop, the
antiskate thing had lost its friction and was not pulling the arm towards the
center of the record, perhaps that is the problem with my turntable?  In the
meantime, I am taking hope a working turntable from here to use.  A working
VCR would also be nice, we have five here and ours needs cleaning (head).

Shining a heat lamp on the dehumidifier will replace the heat of
condensing water (which you want) with the heat from the lamp. That is,
the dehumidification rate will decrease. 

The freezer won't add much heat to the house - only to the extent of its
inefficiency, although there is no reason not to turn inefficiency to an
advantage.

Not much heat is better than no heat at all, and the freezer may at least run
less this way.  It is not cold enough to condense right now, and Jim's
solution was to put the bed up on milk crates and stick a small sealed-type
baseboard heater under it on the lowest setting.  The 'bed' room was nice and
cozy, probably near 50, and the adjacent area got up to 46 by morning.  This
way the bedding will stay dry, too.  May try this solution at home next.  A
high-tech version of the Russian heated sleeping platform (stove).

The two small freezers we have running at present are costing $6/month, or
68 KwH, about 2 kWh/day  2.4 kWh in 24 hours is 100 watts.  We calculated that
it would take 2200 watts to heat the house up from 0 to 70 (with the windows
finished), so 100 watts would raise the temp maybe three degrees, with luck.
43 is better than 40 to work in.

Jim got both dehumidifiers running by just cleaning them and lubricating the
motors, with motor oil, 3-in-1 motor oil, not 3-in-1 oil.  "It's a lot
better'n nuthin."  They are both running now without a heater on them, he is
thinking of using a heat lamp.  Energy efficiency is irrelevant, it is
dehumidification level we are after.
        My computer is making whirring noises.  Does the fan need oiling?  Jim
thinks it may be the hard drive needs replacing (10M, we have lots of them).

Maybe it is full of dust.

The noise stopped after a day.  You may be right, in past tense.

The heat lamp will reduce the dehumidication rate. "Efficiency" ends
up being the ratio of the dehumidication rate to the energy input.
You will get less dehumidication with the heat lamp on. You will get
the maximum dehumidification rate with an additional fan and then
turning off the unit after the ice starts blocking the air flow to
let the ice melt (it continues to dehumidfy while the ice melts).l

How often should it be turned off to melt in a 40 degree house in which the
windows are thickly iced?  55 minutes out of the hour?  What we really need
is a drain on each window, and to heat the house up every hour for 5 minutes.

The upstairs one ran 2 hours before the coils iced completely shut towards
the outside, but the inner coils did not ice up at all.  Dripped dry in about
an hour.  The other one iced up much faster and makes a lot of noise.  We have
decided to tape plastic on the windows to stop condensation and retain heat.
One down, 15 to go.  46 down, 53 up, with a dehumidifier running the space
heater rarely went on.  This bodes well for total heat requirement - a few
light bulbs may do in normal winter weather rather than the calculated 2200
watts to raise it 70 degrees (with no lights, people, or sun shining).  The
city requires that we install heat before plumbing - they may revise this.

The inner coils are the condenser, and they *return* the heat removed in the
evaporator. 

You will have to work out the on/off cycle by trial and error. Turn off the
dehumidifier before the ice plugs the spaces between coils, and turn it on
again after the ice has mostly melted. Keep the fan on all the time.

Jim says 'mostly won't do it, completely melted', or you will slowly get a
buildup of hard ice instead of frost.  One dehumidifer ran for 2 hours before
the ice plugged the spaces, the other a much shorter time.  If we can ever
find the timers, may try turning them on 4 times/day for 2 hours (or less)
each time.  Last night we cut up the rigid fiberglass from the freezer door
(it had been replaced with non-condensing styrofoam) and plugged one window
with it, then taped greenhouse plastic film around the window edges.  If we
plastic all the windows (the others will be left 'clear') that will prevent
condensation on them and also retain more heat until we get around to making
inner R-3 windows, but there is still the problem of moisture getting into
the insulation until we seal it off.
        The ice melted off in maybe half an hour or an hour, we did not time
it and the timing will depend on inside temperature, which varies with outside
temperature.  We will time it when the house is about 40 (very cold out) and
set it for that.  

Jim separated the coils on the model that froze up faster so it would not
clog, and it was okay at 50 for 2 hours, the other is still going strong.

As far as the noisy computer: it's possible that it was the fan, and that the
fan has now stopped & thus no longer makes agonized screeches.  (Should be
easy enough to determine whether the fan is spinning, without even opening
the case.)

Air is still being sucked in the right rear of the computer and blown out the
left rear.  The noise seemed to come from the general vicinity of the hard
drive.  Jim has already copied the contents of it to his laptop drive.

The fan on the longer-running dehumidifier has stopped again, Jim says he has
a similar motor to replace it with and went off to investigate further.  The
bearings may just be shot.

He took apart the fan motor and put some spacers in the bushing shaft (shaft
bushing spacers) which took the play out of the shaft bearing.  Evidently it
had cocked a little and the armature was probably touching the winding (rotor,
stator? whatever it is called).

What would people suggest for oiling a motor that has suddenly developed 
a severe squeaking noise?  Limitations - The motor is very hard to see, 
the oil can't disrupt the ink flow (the motor is on a postage meter), 
the oil can't change the ink color, there is also water very near to the 
motor. (the machine seals envelopes then puts a meter impression on 
them)

I was thinking WD-40.

WD-40 is NOT a lubricant. It acts only while it is present, but it
evaporates quite quickly. The film that remains is not a lubricant.
You might be able to use a hypodermic oiler to reach the shaft close
to the motor - these are available at some hardware stores. They are
usually a plastic tube containing oil with a hypodermic needle attached.

Jim got an oiler from Radio Shack with oil for computers, an oiling pen.
Don't use much.
Both dehumidifiers are running well at 34-39 degrees, on a timer that is on
one hour off two, or on two and off one (one ices up faster).

There is some additive to the oil which reduces dust pickup, a real fine oil.
Teflon additive.

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