On Feb 9, 3:44 pm, Baron wrote:
Seán O'Leathlóbhair wrote:
On Feb 7, 6:20 pm, "Seán O'Leathlóbhair" wrote:
On 7 Feb, 18:05, wrote:

On Feb 7, 10:54 am, Smitty Two wrote:

In article

, "Seán O'Leathlóbhair" wrote:

On Feb 7, 2:28 am, Smitty Two wrote:
In article

,



"Seán O'Leathlóbhair" wrote:

Surely
there are not two simultaneous faults: the element dying
and something wrong in the controller?

I'd be suspect of the test results. The slightest corrosion
on a test lead or the DUT can cause gross errors.

Thanks.

A possibility of course but touching the meter leads together
reads a
fraction of an Ohm or zero if pressed firmly together. It also
r
reads zero when I check the cut-outs. It is a fairly cheap
(not dirt cheap) digital multi-meter and I doubt that it is
very accurate but I don't expect that it will mistake 0 and
infinity.

The terminals of the heater element seem nice and clean. So
clean that I did not think of cleaning them up but I will do
that to be sure.

--
Sean Ó Leathlobhair

Mistaking zero and infinity is a common meter problem, due to
corrosion as I suggested. If the meter probes are clean, what
about the connections on the machine? You're looking at a heating
circuit; heating tends to oxidize metals. Did you scrape them
with an x-acto or similar? The only reason I'm being a pest about
this is that I agree with you that it doesn't seem reasonable in
this case that you have double trouble. I'd also run a cheater
cord from the wall to the heater element as a verification test.

Also double-check the voltage scale on the meter by probing
the mains directly. Reconfirm the reading at the element
terminals once you're convinced the meter is working correctly.
Try the lightbulb test as well - perhaps the controller has a
current sensing feature that shuts down the voltage if the
element is open or one side shorted to earth (for the latter,
that would explain why there's no breaker trip).

Good ideas. In resistance mode, the meter seems to be working but I
will take some of the others' suggestions about cleaning the contacts
just in case. I have not used it to measure large AC voltages for a
while so a fault is possible. If the controller has a current sensor
then I wonder if a bulb will draw enough to trigger it.

I am not sure if I will get time to work on it tonight so there may
be no more news for a couple of days.

As expected no time for the job on Thursday night. Friday night, I
just could not consider the job, it would probably not be safe while
drinking. Due to another problem, we have not TV at the moment but we
managed a nice game of cards which goes well with drinking.

Saturday morning, I attacked the job again with a range of tests as
suggested. The first test was to strap a 240V bulb over the heater
contacts and run the machine. It came on but after a delay. I guess
that there is some sort of motor sensor (I did not get as far as
looking at that) and the controller is waiting for confirmation that
the drum is turning before supplying power. So, my meter test may
have failed because I was not patient enough (I did wait a bit in case
of such a delay) or there is yet another test and it does not supply
power to an open circuit.

So, together with the infinite resistance of the heater (terminals
have been cleaned and the meter checked with some other loads), there
is not much doubt of the problem now and I will be ordering a new
heater element.

I will post later when I have the element and hopefully the dryer is
working again. Thanks everyone for your help.

--
Sean Ó Leathlobhair

According to a colleague there is a thermal device in the door
mechanism!

Odd but the lint trap is just below the door so maybe it is not so
strange. Now that I have seen power applied to the element, I am
reasonably happy that a dead element is to blame. I have ordered one
and I expect to get it Tuesday. So, we can hope for nice dry clothes
Tuesday night. Fortunately, the weather has turned nice and we can
use traditional low-tech drying on the line at the moment.

The element cost me £35 but if it gives me a few more years out of the
machine, it will be money well spent. The machine looks solid and in
good condition otherwise.

--
Sean Ó Leathlobhair

On Feb 9, 7:06 pm, "Seán O'Leathlóbhair" wrote:
On Feb 9, 3:44 pm, Baron wrote:



Seán O'Leathlóbhair wrote:
On Feb 7, 6:20 pm, "Seán O'Leathlóbhair" wrote:
On 7 Feb, 18:05, wrote:

On Feb 7, 10:54 am, Smitty Two wrote:

In article

, "Seán O'Leathlóbhair" wrote:

On Feb 7, 2:28 am, Smitty Two wrote:
In article

,

"Seán O'Leathlóbhair" wrote:

Surely
there are not two simultaneous faults: the element dying
and something wrong in the controller?

I'd be suspect of the test results. The slightest corrosion
on a test lead or the DUT can cause gross errors.

Thanks.

A possibility of course but touching the meter leads together
reads a
fraction of an Ohm or zero if pressed firmly together. It also
r
reads zero when I check the cut-outs. It is a fairly cheap
(not dirt cheap) digital multi-meter and I doubt that it is
very accurate but I don't expect that it will mistake 0 and
infinity.

The terminals of the heater element seem nice and clean. So
clean that I did not think of cleaning them up but I will do
that to be sure.

--
Sean Ó Leathlobhair

Mistaking zero and infinity is a common meter problem, due to
corrosion as I suggested. If the meter probes are clean, what
about the connections on the machine? You're looking at a heating
circuit; heating tends to oxidize metals. Did you scrape them
with an x-acto or similar? The only reason I'm being a pest about
this is that I agree with you that it doesn't seem reasonable in
this case that you have double trouble. I'd also run a cheater
cord from the wall to the heater element as a verification test.

Also double-check the voltage scale on the meter by probing
the mains directly. Reconfirm the reading at the element
terminals once you're convinced the meter is working correctly.
Try the lightbulb test as well - perhaps the controller has a
current sensing feature that shuts down the voltage if the
element is open or one side shorted to earth (for the latter,
that would explain why there's no breaker trip).

Good ideas. In resistance mode, the meter seems to be working but I
will take some of the others' suggestions about cleaning the contacts
just in case. I have not used it to measure large AC voltages for a
while so a fault is possible. If the controller has a current sensor
then I wonder if a bulb will draw enough to trigger it.

I am not sure if I will get time to work on it tonight so there may
be no more news for a couple of days.

As expected no time for the job on Thursday night. Friday night, I
just could not consider the job, it would probably not be safe while
drinking. Due to another problem, we have not TV at the moment but we
managed a nice game of cards which goes well with drinking.

Saturday morning, I attacked the job again with a range of tests as
suggested. The first test was to strap a 240V bulb over the heater
contacts and run the machine. It came on but after a delay. I guess
that there is some sort of motor sensor (I did not get as far as
looking at that) and the controller is waiting for confirmation that
the drum is turning before supplying power. So, my meter test may
have failed because I was not patient enough (I did wait a bit in case
of such a delay) or there is yet another test and it does not supply
power to an open circuit.

So, together with the infinite resistance of the heater (terminals
have been cleaned and the meter checked with some other loads), there
is not much doubt of the problem now and I will be ordering a new
heater element.

I will post later when I have the element and hopefully the dryer is
working again. Thanks everyone for your help.

--
Sean Ó Leathlobhair

According to a colleague there is a thermal device in the door
mechanism!

Odd but the lint trap is just below the door so maybe it is not so
strange. Now that I have seen power applied to the element, I am
reasonably happy that a dead element is to blame. I have ordered one
and I expect to get it Tuesday. So, we can hope for nice dry clothes
Tuesday night. Fortunately, the weather has turned nice and we can
use traditional low-tech drying on the line at the moment.

The element cost me £35 but if it gives me a few more years out of the
machine, it will be money well spent. The machine looks solid and in
good condition otherwise.

I got the new element today as expected. For interest, I measured its
resistance and got the plausible reading of 26Ohms. It went in easily
and better still it works. The only thing wrong is that I have lost
one screw but there are so many holding the back panel on that I think
it will hold together with one missing.

Thanks again everyone for your help.

--
Sean Ó Leathlobhair