electric fan oven keeps cutting out and resetting?

[jim]

Our De Dietrich elec double oven has developed an annoying habit of cutting out (totally including display, all fans etc) when run at "normal" cooking temperatures (~220 deg c). After a few minutes (presumably cooling) the oven comes back to life - though behaving as if there had been a power cut (clock at 0:00, flashing display etc). It can then be turned back on and the problem will repeat.

=46rom a googling it seems it might be some sort of "overheat thermostat" cost =A325 ish -

can anyone offer guidance please? e.gs:- The oven is a double one - should I expect to find more than one of these thermostats? How will I know which one is the culprit if there are more than one? Can I test the present thermostat(s) somehow? Can anyone recommend a supplier?

Many thanks in advance for any help Jim

[Frank Erskine]

I wonder if it could be some problem with an RCD, if any, at the consumer unit. Perhaps overheating and breaking contact temporarily.

[jim]

yes that was my very first thought, but the cooker wall switch neon (and socket next to it) have power all through the episodes i.e.

*nothing* touched on distbn board at all...

[Andrew Gabriel]

Don't know that model, but does it have a case cooling fan? Maybe that has failed and the case is overheating?

[jim]

it's a FM4942 built-under double oven model - and yes it has a cooling fan which appears to be OK and blows warm air out from just below the control panel (except when it cuts out- when everything on it stops)

[John D.W.]

I was about to suggest this - My Tricity oven has a (small) cooling fan=20 near the switches that blows cold air from a duct from a low-level vent=20 over the electronics. It is prone to sucking dust, etc. that, over time,=20 reduces its efficiency. Such fans don't necessarily have to fail=20 completely, since the layer of dust over the blades reduces their=20 efficiency, just like in a computer... On mine, the fan only comes on=20 when things are getting a little hot. If, then, it isn't providing=20 enough cooling air, an electronic cut-out switches everything off. The=20 fix is to stip-down and clean the accumulated muck.

If the switches are above the oven door, also check the door seal is=20 still working, reducing the heat flow up to the switches. Mine is more=20 prone to cut-out if I use the top oven, which has a drop-down door,=20 which doesn't seal as well along the top.=20

If there isn't a fan cooling the electronics, consider installing one (a=20

240v one).

Replacing the overheat thermostat won't necessarily fix the problem,=20 since it is probably the operation of this that is cutting off the=20 supply, suggesting it is doing its job. It could be operating at a too=20 low temperature, but that isn't a usual failure mode.

--=20 John W To mail me replace the obvious with co.uk twice

[jim]

finally got around to sorting this one out (pesky newborn kids taking all my tinkering time etc)

I checked the fan and although not pristine it wasn't caked in grease/ dust so I didn't clean it - however what seems to have happened is that when I replaced the fan element the last time (with a genuine part) I distyrned the mineral quilt type insulation around the overheat thermostat on the lower oven. In effect I had put a duvet over the thermostat which seems to explain why it was tripping out at just 215 deg C. Just had the oven upto 275 deg C (confirmed by an oven thermometer) and no problems at all.

Excellent! Sincere thanks to all who responded with tips and advice to help get me sorted.

Cheers Jim