On Monday, 11 November 2019 11:27:15 UTC, Jeff Layman wrote:
On 10/11/19 13:04, Jeff Layman wrote:
Last year we had a problem with our 5-year old Beko tripping the RCD
when it was turned on (NB it had been modified during a recall shortly
after we bought it). It only did it on that one day and has been fine since.

A month ago it ran through its drying cycle with no problem, and beeped
that it had finished. We removed the dry washing, and took it away. When
we returned a couple of minutes later, we found the RCD had tripped.
This has occurred twice again - the dryer is fine working, but trips the
RCD as it cools down. Once cool, it seems ok and can be used again.

I'll have a look inside to see if there's anything obvious, but has
anyone heard of a fault which behaves this way?

It may be time for a new drier, but I'm intrigued as to what this one is
doing.

I had a look inside, and the only part before the mains switch
(double-pole, by the way) is the interference filter. It was a little
sticky to touch, and might have leaked some of the potting, but it was
difficult to tell. I removed it, and found it was marked:
D.E.M. F£CF75005t
0.15uF (X1) + 1Mohm
2 x 0.027uF (Y2)
250V 50/60Hz 16A/40degC
HMF 25/100/21C

There is a diagram too showing a 0.15uF + 1Mohm across the mains, and
0.027uF caps from live and neutral to earth.

With a multimeter it read 1Mohm across Live - Neutral. Live - earth and
neutral - earth read open circuit (took a few seconds to get there at
20M range as the caps charged. Test voltage is only 0.3V). It was, of
course, not possible to check the 0.15uF capacitor. On the capacitance
range, Live - earth read 0.048uF, and neutral - earth 0.067uF.

It looked cheap enough to replace anyway, but:
https://www.bekospares.co.uk/tumble-dryer/dcu7230w-7182681500/interference-filter/product.pl?pid=4824596&path=634351&model_ref=98543 2
No alternative listed, either.

Similar results at Partmaster (and other identical sites - do they all
get them from Beko anyway?!), and others don't list it at all. It is
available on eBay as a "genuine Beko part", but why there and not at
other sites? I'll do a bit more checking on alternative interference
filters, even if a small modification is required, as I'm not happy
using an identical part which might be dodgy.

Your machine will work fine without it. Any brand is fine as a replacement. The values aren't critical.


NT