I've fitted the new thermal fuse and bingo! It works again. Now for
the Hoover PurePower 1900w.

However, the cut-out on the Hoover is different in that the thing cuts
out, then you leave it for two to three minutes and it will start
again. The time until cut-out gets shorter and shorter.

The Panasonic's fuse OTOH was a one-time "blow", never to work again,
which figured, as it gave no warning at all when it stopped working.

So, my question, before I start dismantling the Hoover: will the
thermal fuse look similar to the Panaonic's e.g. one of these:
http://images.asia.ru/img/alibaba/ph...ermal_fuse.jpg

or will it be a different shape? Will it be an inline thing in the
brown cable like on the Pansonic, or a little black box with
connectors?

By the way, the repair for the Panasonic cost me 69p for the fuse and
£1.29 for a 10x packet of crimp-on butt connectors, 9 of which I've
got left.

MM

In article ,
MM wrote:
've fitted the new thermal fuse and bingo! It works again. Now for
the Hoover PurePower 1900w.

However, the cut-out on the Hoover is different in that the thing cuts
out, then you leave it for two to three minutes and it will start
again. The time until cut-out gets shorter and shorter.

A re-setting one. I had a Plasplugs tile cutter that did that. Don't think
any series wound motor can cope with continuous use - unless very well
cooled.

The Panasonic's fuse OTOH was a one-time "blow", never to work again,
which figured, as it gave no warning at all when it stopped working.

So, my question, before I start dismantling the Hoover: will the
thermal fuse look similar to the Panaonic's e.g. one of these:
http://images.asia.ru/img/alibaba/ph...ermal_fuse.jpg

or will it be a different shape? Will it be an inline thing in the
brown cable like on the Pansonic, or a little black box with
connectors?

Probably quite a bit larger. But of course it may be tripping for a
reason. Make sure a bearing hasn't seized, etc, and that the motor cooling
hasn't got blocked.

By the way, the repair for the Panasonic cost me 69p for the fuse and
£1.29 for a 10x packet of crimp-on butt connectors, 9 of which I've
got left.

It gives you a nice warm feeling. Especially when a Maplin shop actually
stocks some components. ;-)

--
*'ome is where you 'ang your @ *

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
MM writes:
I've fitted the new thermal fuse and bingo! It works again. Now for
the Hoover PurePower 1900w.

However, the cut-out on the Hoover is different in that the thing cuts
out, then you leave it for two to three minutes and it will start
again. The time until cut-out gets shorter and shorter.

The Panasonic's fuse OTOH was a one-time "blow", never to work again,
which figured, as it gave no warning at all when it stopped working.

The thermal fuses tripping are normally symptoms of another problem.
Did you identify what the original problem was?

So, my question, before I start dismantling the Hoover: will the
thermal fuse look similar to the Panaonic's e.g. one of these:
http://images.asia.ru/img/alibaba/ph...ermal_fuse.jpg

No.

Might look like
http://cpc.farnell.com/productimages...d/42419936.jpg
but there are other styles.

However, you should be fixing whatever is causing the overheating.
It sounds like the thermal switch is working fine. (These ones can
go wrong and develop contact resistance which self-heats them, but
that's not what I would assume to start with.)

More likely faults are reduced air-flow (hence insufficient cooling)
caused by blocked airway or filters, motor bearing over-heating,
motor winding shorted and overheating (often caused initially by
over-heating due to reduced air-flow).

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

In message , MM
wrote
I've fitted the new thermal fuse and bingo! It works again. Now for
the Hoover PurePower 1900w.

However, the cut-out on the Hoover is different in that the thing cuts
out, then you leave it for two to three minutes and it will start
again. The time until cut-out gets shorter and shorter.

The Panasonic's fuse OTOH was a one-time "blow", never to work again,
which figured, as it gave no warning at all when it stopped working.

So, my question, before I start dismantling the Hoover: will the
thermal fuse look similar to the Panaonic's e.g. one of these:
http://images.asia.ru/img/alibaba/ph...ermal_fuse.jpg

It's probably not the thermal fuse/cut-out which is working correctly.
The cut-out will be mechanically fixed to something that is getting too
hot. Switch the appliance off for a couple of minutes the faulty item
will cool down to the threshold point below which the correctly working
cut-out kicks back in. The faulty item will still be very hot and it
will not take much to heat it to the upper temperature threshold point
of the cut-out again.

Assuming no problems such as shorted windings, it may be that on
dismantling the Hoover you may find an accumulation of dust or lint
restricting airflow to something that is normally cooled in a forced
airflow.


or will it be a different shape? Will it be an inline thing in the
brown cable like on the Pansonic, or a little black box with
connectors?

It may be something like a thermal switch
http://cpc.farnell.com/honest-well/t...switch-no-90-c
/dp/SW03183?MER=e-bb45-00001002

--
Alan
news2009 {at} admac {dot} myzen {dot} co {dot} uk

"Andrew Gabriel" wrote in message
...
In article ,
MM writes:
I've fitted the new thermal fuse and bingo! It works again. Now for
the Hoover PurePower 1900w.

However, the cut-out on the Hoover is different in that the thing cuts
out, then you leave it for two to three minutes and it will start
again. The time until cut-out gets shorter and shorter.

The Panasonic's fuse OTOH was a one-time "blow", never to work again,
which figured, as it gave no warning at all when it stopped working.

The thermal fuses tripping are normally symptoms of another problem.
Did you identify what the original problem was?


Pure age can be another. I've had a few go on items like chip fryers where
there hasn't been any over temperature.

On Fri, 26 Jun 2009 15:21:17 +0100, "Dave Plowman (News)"
wrote:

In article ,
MM wrote:
've fitted the new thermal fuse and bingo! It works again. Now for
the Hoover PurePower 1900w.

However, the cut-out on the Hoover is different in that the thing cuts
out, then you leave it for two to three minutes and it will start
again. The time until cut-out gets shorter and shorter.

A re-setting one. I had a Plasplugs tile cutter that did that. Don't think
any series wound motor can cope with continuous use - unless very well
cooled.

The Panasonic's fuse OTOH was a one-time "blow", never to work again,
which figured, as it gave no warning at all when it stopped working.

So, my question, before I start dismantling the Hoover: will the
thermal fuse look similar to the Panaonic's e.g. one of these:
http://images.asia.ru/img/alibaba/ph...ermal_fuse.jpg

or will it be a different shape? Will it be an inline thing in the
brown cable like on the Pansonic, or a little black box with
connectors?

Probably quite a bit larger. But of course it may be tripping for a
reason. Make sure a bearing hasn't seized, etc, and that the motor cooling
hasn't got blocked.

I completely dismantled the motor and housing etc. There WAS a fair
bit of carpet fluff in the impeller part of the motor, but on
reassembling everything after a thorough clean the cutting out still
occurs.

MM

On 26 Jun 2009 14:29:41 GMT, (Andrew
Gabriel) wrote:

In article ,
MM writes:
I've fitted the new thermal fuse and bingo! It works again. Now for
the Hoover PurePower 1900w.

However, the cut-out on the Hoover is different in that the thing cuts
out, then you leave it for two to three minutes and it will start
again. The time until cut-out gets shorter and shorter.

The Panasonic's fuse OTOH was a one-time "blow", never to work again,
which figured, as it gave no warning at all when it stopped working.

The thermal fuses tripping are normally symptoms of another problem.
Did you identify what the original problem was?

Not until I dismantled the motor and housing. The impeller part of the
motor (inside the big round mounting boss) was stuffed full of carpet
fluff. I had to use tweezers to prise some of it out.

However, after a thorough clean and reassembly, the cutting out still
occurs.


So, my question, before I start dismantling the Hoover: will the
thermal fuse look similar to the Panaonic's e.g. one of these:
http://images.asia.ru/img/alibaba/ph...ermal_fuse.jpg

No.

Might look like
http://cpc.farnell.com/productimages...d/42419936.jpg
but there are other styles.

Having now dismantled the machine I have not found ANYthing that could
be a thermal fuse, at least, not at the motor end. Inside the handle
there is a small PCB (approx 50mm x 40mm) to which the cables to and
from the switch are connected. The PCB has what looks like a
capacitor, since it's marked uF. It is yellow, rectangular, about 20mm
x 15 x 5. There is also a resistor and what looks like a voltage
regulator.

Could the thermal protection be an integral part of the motor?

MM

In article ,
MM writes:

Not until I dismantled the motor and housing. The impeller part of the
motor (inside the big round mounting boss) was stuffed full of carpet
fluff. I had to use tweezers to prise some of it out.

However, after a thorough clean and reassembly, the cutting out still
occurs.

Does the motor spin freely by hand (or are bearings stiff)?
Does motor slow down before cutting out? That can be caused
by windings which have been damaged by overheating and start
shorting out.

Could also be knackered brushes, although failure symptoms
are usually a bit different.

Having now dismantled the machine I have not found ANYthing that could
be a thermal fuse, at least, not at the motor end. Inside the handle
there is a small PCB (approx 50mm x 40mm) to which the cables to and
from the switch are connected. The PCB has what looks like a
capacitor, since it's marked uF. It is yellow, rectangular, about 20mm
x 15 x 5.

Probably interferance suppressor.

There is also a resistor and what looks like a voltage
regulator.

Could the thermal protection be an integral part of the motor?

Yes.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On 27 Jun 2009 20:36:33 GMT, (Andrew
Gabriel) wrote:

In article ,
MM writes:

Not until I dismantled the motor and housing. The impeller part of the
motor (inside the big round mounting boss) was stuffed full of carpet
fluff. I had to use tweezers to prise some of it out.

However, after a thorough clean and reassembly, the cutting out still
occurs.

Does the motor spin freely by hand (or are bearings stiff)?

Yes.

Does motor slow down before cutting out?

No. It just stops as if I had switched off the switch.

That can be caused
by windings which have been damaged by overheating and start
shorting out.

Could also be knackered brushes, although failure symptoms
are usually a bit different.

No, the brushes are fine. The machine has had very little use.

Having now dismantled the machine I have not found ANYthing that could
be a thermal fuse, at least, not at the motor end. Inside the handle
there is a small PCB (approx 50mm x 40mm) to which the cables to and
from the switch are connected. The PCB has what looks like a
capacitor, since it's marked uF. It is yellow, rectangular, about 20mm
x 15 x 5.

Probably interferance suppressor.

That's what I think. The Panasonic also has a cap, but it is just
loose on the wires, not mounted on a PCB.


There is also a resistor and what looks like a voltage
regulator.

Could the thermal protection be an integral part of the motor?

Yes.

That would be the worst situation, since new motors (I'm told) are
unobtainable for this model. Even if they were they'd cost more than
an equivalent new machine. One web site I looked at said £59.99 (for
the motor [though not in stock and no info re restocking]) and I only
paid £34 for the machine in the first place.

Thanks for getting back to me. The Panasonic is still going great
guns! The Hoover looks like it's destined for the tip, though, since I
expect the motor is a sealed unit. It looks pretty much like it.

MM