Some advice please.

Smallish floor mounted dehumidifier on casters, about size of a small
filing cabinet.

The colour and style of the overall unit suggest it was the sort of
thing sold by say Sears some 20+ years ago. (We also have a newer one
that is very similar but different colour and details).

Problem. Compressor runs but after a few minutes cuts out.

Problem has been tracked down to the compressor itself. It's a
typical fridge type sealed compressor. The compressor is marked as
follows;

"aose a" , "115 v 60 Hz", also "A5160A 144CG25". The compressor is
also labelled "Thermally protected".

After checking and bypassing all other parts of the circuit (the
humidistat, drip pan float switch and some sort of 'cut-out' clipped
to the output end of the cooling coils are all OK) it is found the
compressor runs but shuts down after several minutes without getting
particularly warm!

On the side of the compressor, plugged into two of the three pins
projecting from the sealed unit, is a typical compressor starter
relay marked [FSP] "920235" and "960A042-172" and "P4S".

Adjacent to the starter relay under the same cover and in series with
the hot lead from supply to the starter relay is a round bi-metal
device which the mounting clip presses against the outer surface of
the compressor. It is marked Klixon and "MR26ALK-3164" and "T.150-IK45
[FSP] 950234".
We presumed this circular device to be a bi-metal thermal protection
switch. However when it is temporarily by-passed the whole unit runs,
the cooling coils start to form frost but the compressor still cuts
out after a few minutes.

Is there another thermal protection circuit inside the sealed unit????
And if so there is presumably no way for a DIYer to fix it, nor would
it be worthwhile/safe to attempt. Correct?

We were going to chuck this unit but decided to give it another try
before doing so. Any knowledgeable advice would be most welcome.TIA.

BTW the unit is marked R12 (refrigerant) so if we dispose of it we
will call the Environment/Recycling people to determine where to take
it.

Although in one middle - eastern country where we were for several
years have seen car AC systems 'serviced' by letting the refrigerant
blow off and then recharging the whole thing!

It's very possible the start relay is bad. Not a likely
problem, as it does run for a few seconds or moments. Sounds
more like the compressor berrings are worn out, and the
internal friction is too great for the motor.

If the problem were dirty condensor, the compressor would be
too hot to touch. You ruled out several of the other
possibilities.

There are hard start kits made for compressors, but might
not be worth the bother. An appliance shop may be able to
fit it with a hard start kit. And, it may keep doing the
same problem.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"terry" wrote in message
...
Some advice please.

Smallish floor mounted dehumidifier on casters, about size
of a small
filing cabinet.

The colour and style of the overall unit suggest it was the
sort of
thing sold by say Sears some 20+ years ago. (We also have a
newer one
that is very similar but different colour and details).

Problem. Compressor runs but after a few minutes cuts out.

Problem has been tracked down to the compressor itself.
It's a
typical fridge type sealed compressor. The compressor is
marked as
follows;

"aose a" , "115 v 60 Hz", also "A5160A 144CG25". The
compressor is
also labelled "Thermally protected".

After checking and bypassing all other parts of the circuit
(the
humidistat, drip pan float switch and some sort of 'cut-out'
clipped
to the output end of the cooling coils are all OK) it is
found the
compressor runs but shuts down after several minutes without
getting
particularly warm!

On the side of the compressor, plugged into two of the three
pins
projecting from the sealed unit, is a typical compressor
starter
relay marked [FSP] "920235" and "960A042-172" and "P4S".

Adjacent to the starter relay under the same cover and in
series with
the hot lead from supply to the starter relay is a round
bi-metal
device which the mounting clip presses against the outer
surface of
the compressor. It is marked Klixon and "MR26ALK-3164" and
"T.150-IK45
[FSP] 950234".
We presumed this circular device to be a bi-metal thermal
protection
switch. However when it is temporarily by-passed the whole
unit runs,
the cooling coils start to form frost but the compressor
still cuts
out after a few minutes.

Is there another thermal protection circuit inside the
sealed unit????
And if so there is presumably no way for a DIYer to fix it,
nor would
it be worthwhile/safe to attempt. Correct?

We were going to chuck this unit but decided to give it
another try
before doing so. Any knowledgeable advice would be most
welcome.TIA.

BTW the unit is marked R12 (refrigerant) so if we dispose of
it we
will call the Environment/Recycling people to determine
where to take
it.

Although in one middle - eastern country where we were for
several
years have seen car AC systems 'serviced' by letting the
refrigerant
blow off and then recharging the whole thing!

On Jun 14, 2:31*am, "Stormin Mormon"
wrote:
It's very possible the start relay is bad. Not a likely
problem, as it does run for a few seconds or moments. Sounds
more like the compressor bearings are worn out, and the
internal friction is too great for the motor.

If the problem were dirty condensor, the compressor would be
too hot to touch. You ruled out several of the other
possibilities.

There are hard start kits made for compressors, but might
not be worth the bother. An appliance shop may be able to
fit it with a hard start kit. And, it may keep doing the
same problem.

-----------------------------------------------------------------------------------------------------------------------------------------------
Thank you Christopher: Your reply is most appreciated.

Yes the unit does run for about a minute or two; so one thinks "Ah OK,
it's going to work OK" but then it cuts out.
Also it does seem to stop rather abruptly/roughly (the compressor
makes quite a physical kick as it stops!) which might suggest bad
bearings?

Or in other words it's worn out (after all I did get it for nothing
although it did seem to work sometimes for a couple of years!).

Didn't think of a defective starter; cos that looks OK and seems to
test OK? But may have another used starter from an old fridge,
somewhere that can try.

Or maybe can simulate the action of the starter relay.; which I think
is that the relay pulls up by the higher initial current of the
compressor motor at rest, which closes a contact to the starting
winding. Once motor is running the relay presumably drops back opening
the starting contact? Like, on a very small scale the procedure for
manually starting those old style big industrial motors!

Thanks indeed for the suggestions and about possibility of bad
bearings; hadn't thought of that.

My regards; thank you. terry

PS. If successful will post follow up.
..

On Jun 14, 9:45*pm, "Stormin Mormon"
wrote:
So, the starter tests OK. How did you test it?

--
Christopher A. Young
Learn more about Jesus
*www.lds.org
.

"stan" wrote in message

...
-----------------------------------------------------------------------
Thank you Christopher: Your reply is most appreciated.

Yes the unit does run for about a minute or two; so one
thinks "Ah OK,
it's going to work OK" but then it cuts out.
Also it does seem to stop rather abruptly/roughly (the
compressor
makes quite a physical kick as it stops!) which might
suggest bad
bearings?

Or in other words it's worn out (after all I did get it for
nothing
although it did seem to work sometimes for a couple of
years!).

Didn't think of a defective starter; cos that looks OK and
seems to
test OK? But may have another used starter from an old
fridge,
somewhere that can try.

Or maybe can simulate the action of the starter relay.;
which I think
is that the relay pulls up by the higher initial current of
the
compressor motor at rest, which closes a contact to the
starting
winding. Once motor is running the relay presumably drops
back opening
the starting contact? Like, on a very small scale the
procedure for
manually starting those old style big industrial motors!

Thanks indeed for the suggestions and about possibility of
bad
bearings; hadn't thought of that.

My regards; thank you. terry

PS. If successful will post follow up.
.

Follow up.

Well it is NOT the compressor internal or external thermal cut-out/
protection; I should have realized earlier there IS another element in
the circuit!

Most of the controls, humidistat, drip pan float switch, etc. are in
the live lead to the compressor circuitry. However there is one item
which appears to be some sort of temperature sensor which is/was wired
into the neutral side of only the compressor!

It is circular, sealed, has no means of adjustment and was clipped
onto the exiting end of the cooling coils.

The printing on it is very faint but appears to be "37T32 29531 59-20"
Also "F?20009-052 and 201?M?73" But that last group of 8 characters is
very indistinct indeed.

After removing it the rest of the unit operates fully, it starts
normally and frost quickly forms on the cooling coils. So the
immediate conclusion was that this 'cold control' switch is maybe
faulty or operating too soon at too high a temperature?

So a question might be; is this gadget supposed to open the compressor
ctcuit to allow, say, the coils to periodically defrost and/or is it
opening at much too high a temperature.

If opening at too high a temperature maybe it should be reinstalled
and located differently so as to not operate so soon?

Any further advice most welcome.

Also the knob is broken off the humidistat but that can be repaired.
Adjusting the humidistat (basicall a micro-witch with a sensor) shows
that it is working.

Further advice welcomed.

"stan" wrote in message
...
On Jun 14, 9:45 pm, "Stormin Mormon"
wrote:
So, the starter tests OK. How did you test it?

--
Christopher A. Young
Learn more about Jesus
www.lds.org
.

"stan" wrote in message

...
-----------------------------------------------------------------------
Thank you Christopher: Your reply is most appreciated.

Yes the unit does run for about a minute or two; so one
thinks "Ah OK,
it's going to work OK" but then it cuts out.
Also it does seem to stop rather abruptly/roughly (the
compressor
makes quite a physical kick as it stops!) which might
suggest bad
bearings?

Or in other words it's worn out (after all I did get it for
nothing
although it did seem to work sometimes for a couple of
years!).

Didn't think of a defective starter; cos that looks OK and
seems to
test OK? But may have another used starter from an old
fridge,
somewhere that can try.

Or maybe can simulate the action of the starter relay.;
which I think
is that the relay pulls up by the higher initial current of
the
compressor motor at rest, which closes a contact to the
starting
winding. Once motor is running the relay presumably drops
back opening
the starting contact? Like, on a very small scale the
procedure for
manually starting those old style big industrial motors!

Thanks indeed for the suggestions and about possibility of
bad
bearings; hadn't thought of that.

My regards; thank you. terry

PS. If successful will post follow up.
.

Follow up.

Well it is NOT the compressor internal or external thermal cut-out/
protection; I should have realized earlier there IS another element in
the circuit!

Most of the controls, humidistat, drip pan float switch, etc. are in
the live lead to the compressor circuitry. However there is one item
which appears to be some sort of temperature sensor which is/was wired
into the neutral side of only the compressor!

It is circular, sealed, has no means of adjustment and was clipped
onto the exiting end of the cooling coils.

The printing on it is very faint but appears to be "37T32 29531 59-20"
Also "F?20009-052 and 201?M?73" But that last group of 8 characters is
very indistinct indeed.

After removing it the rest of the unit operates fully, it starts
normally and frost quickly forms on the cooling coils. So the
immediate conclusion was that this 'cold control' switch is maybe
faulty or operating too soon at too high a temperature?

So a question might be; is this gadget supposed to open the compressor
ctcuit to allow, say, the coils to periodically defrost and/or is it
opening at much too high a temperature.

If opening at too high a temperature maybe it should be reinstalled
and located differently so as to not operate so soon?

Any further advice most welcome.

Also the knob is broken off the humidistat but that can be repaired.
Adjusting the humidistat (basicall a micro-witch with a sensor) shows
that it is working.

Further advice welcomed.

I have not read this entire thread but it seems to me that your unit might
be low on refrigerant. I don't think the coil temperature should be below
freezing (frosting). If the coil is frosting at the inlet (small pipe) end
and is a lot warmer at the other end, it is almost surely low on
refrigerant.

Don Young

"Don Young" wrote in message
webinternetservicesprovideinc...


Follow up.

Well it is NOT the compressor internal or external thermal
cut-out/
protection; I should have realized earlier there IS another
element in
the circuit!

Most of the controls, humidistat, drip pan float switch,
etc. are in
the live lead to the compressor circuitry. However there is
one item
which appears to be some sort of temperature sensor which
is/was wired
into the neutral side of only the compressor!

It is circular, sealed, has no means of adjustment and was
clipped
onto the exiting end of the cooling coils.

CY: Sounds a lot like a freeze stat.

The printing on it is very faint but appears to be "37T32
29531 59-20"
Also "F?20009-052 and 201?M?73" But that last group of 8
characters is
very indistinct indeed.

After removing it the rest of the unit operates fully, it
starts
normally and frost quickly forms on the cooling coils. So
the
immediate conclusion was that this 'cold control' switch is
maybe
faulty or operating too soon at too high a temperature?

CY: Perhaps. Since the freeze stat trips too soon......

So a question might be; is this gadget supposed to open the
compressor
ctcuit to allow, say, the coils to periodically defrost
and/or is it
opening at much too high a temperature.

CY: If it's what I think, it's to prevent the evaporator
coil from turning into a block of ice. The coil only needs
to be in the thirties or forties to condense water out of
the air.

If opening at too high a temperature maybe it should be
reinstalled
and located differently so as to not operate so soon?

Any further advice most welcome.

CY: Might be the unit is low freon, and getting cold too
fast, or the freeze stat is too sensetive. I'd be tempted to
try a couple wraps of electrical tape around the tube, and
then put the freeze stat back on. Maybe that will slow it
down.

Also the knob is broken off the humidistat but that can be
repaired.
Adjusting the humidistat (basicall a micro-witch with a
sensor) shows
that it is working.

Further advice welcomed.

I have not read this entire thread but it seems to me that
your unit might
be low on refrigerant. I don't think the coil temperature
should be below
freezing (frosting). If the coil is frosting at the inlet
(small pipe) end
and is a lot warmer at the other end, it is almost surely
low on
refrigerant.

CY: It's normal to frost a bit where the cap tube goes into
the evaporator. But, most or all of the evaporator (cold
coil) should be cold.

Don Young

On Jun 16, 12:05*am, "Don Young" wrote:

I have not read this entire thread but it seems to me that your unit might
be low on refrigerant. I don't think the coil temperature should be below
freezing (frosting). If the coil is frosting at the inlet (small pipe) end
and is a lot warmer at the other end, it is almost surely low on
refrigerant.

Don Young- Hide quoted text -

- Show quoted text -

Thanks Don: But don't think so! Now that I've got the unit to run
without cutting out after each couple of minutes it forms a heavy coat
of frosty ice evenly over the whole of the coil. The icing starts at
the input end of the coil and then just builds all over it.
Just like the other unit we have. That other unit especially when it
is at a humidistat setting that is too low for the basement area temp.
of around 55 to 60 degrees F builds up a layer of ice which and does
not stop to allow it melt off.

With (what I will call the temperature switch) removed the unit runs
continuously and all other aspects of the unit seem to be OK!

But I'm still not clear of the function of that device which was
clipped to outlet pipe of the cooling coils on it's way back to the
compressor! And was the only cut out in the neutral lead to the
compressor! Maybe it's function is to sense that the coils have
reached freezing? So then it stops the compressor allowing the ice to
melt off the coils. Thereby accomplishing de-humidification?

Anyway tomorrow will place the humidistat where it is normally,
directly in the air flow out of the unit, and see it how reacts when
the unit is plugged in and is run continuously. Looks like am getting
close to solution!

"stan" wrote in message
...

Thanks Don: But don't think so!
CY: Oh, why not!


Now that I've got the unit to run
without cutting out after each couple of minutes it forms a
heavy coat
of frosty ice evenly over the whole of the coil. The icing
starts at
the input end of the coil and then just builds all over it.
CY: Normally, that happens for the first few minutes, and
then frost coat melts off. If the frost stays, the unit is
probably low on freon.


Just like the other unit we have. That other unit especially
when it
is at a humidistat setting that is too low for the basement
area temp.
of around 55 to 60 degrees F builds up a layer of ice which
and does
not stop to allow it melt off.
CY: I've seen ice blocks on the back of dehum.


With (what I will call the temperature switch) removed the
unit runs
continuously and all other aspects of the unit seem to be
OK!

But I'm still not clear of the function of that device which
was
clipped to outlet pipe of the cooling coils on it's way back
to the
compressor!
CY: It's probably a freeze stat!

And was the only cut out in the neutral lead to the
compressor!
CY: Well! That's all it has to!


Maybe it's function is to sense that the coils have
reached freezing? So then it stops the compressor allowing
the ice to
melt off the coils. Thereby accomplishing de-humidification?
CY: Yes! Exactly!


Anyway tomorrow will place the humidistat where it is
normally,
directly in the air flow out of the unit, and see it how
reacts when
the unit is plugged in and is run continuously. Looks like
am getting
close to solution!
CY: Sounds like you need a new freeze stat! And I wore out
my! exclaimation point! key!