Broken fan assisted oven

[vera]

Make: NEFF Model: B1421W

My oven caused the circuit breaker/trip switch to 'trip' the other day
Everything seems to work fine now except it won't generate any heat whe
using the oven - the grill works fine though.

A work colleague said it could be the element and that he'd replace
one before and it wasn't too difficult. I first pulled the oven out an
took the back cover off. I quickly realised I should be opening it u
from the inside to get to the element, but noticed two scorch mark
(see back_view.jpg, scorch1.jpg and scorch2.jpg) on the insulatin
material. I still thought my best bet was the element so put the bac
cover back on and went to look inside.

The element looks fine to me (see inside.jpg and element2.jpg) and
couldn't remove the fan itself in order to investigate behind the bac
panel of the oven interior.

Are the scorch marks 'normal' or are they a likely cause of the ove
not heating? If they are related, what could have caused them? I'
expect them to be closer together (they're on either side of the oven)
but that's only because the two wires connecting to the element enter a
the same point and also the scorch marks don't look like they wer
caused by heat from the inside, though there's nothing between all th
gubbins at the back and the exterior panel at the back that looks t
have caused them either.

All advice most appreciated. The oven is only 3 years old and I'd lik
to repair it myself if possible - with the help of some knowledgeabl
folk on this board of course!

Many thanks in advance,

\/er

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[Rheilly Phoull]

One day vera got dressed and committed to text

Make: NEFF Model: B1421W

My oven caused the circuit breaker/trip switch to 'trip' the other
day. Everything seems to work fine now except it won't generate any
heat when using the oven - the grill works fine though.

A work colleague said it could be the element and that he'd replaced
one before and it wasn't too difficult. I first pulled the oven out
and took the back cover off. I quickly realised I should be opening
it up from the inside to get to the element, but noticed two scorch
marks (see back_view.jpg, scorch1.jpg and scorch2.jpg) on the
insulating material. I still thought my best bet was the element so
put the back cover back on and went to look inside.

The element looks fine to me (see inside.jpg and element2.jpg) and I
couldn't remove the fan itself in order to investigate behind the back
panel of the oven interior.

Are the scorch marks 'normal' or are they a likely cause of the oven
not heating? If they are related, what could have caused them? I'd
expect them to be closer together (they're on either side of the
oven), but that's only because the two wires connecting to the
element enter at the same point and also the scorch marks don't look
like they were caused by heat from the inside, though there's nothing
between all the gubbins at the back and the exterior panel at the
back that looks to have caused them either.

All advice most appreciated. The oven is only 3 years old and I'd like
to repair it myself if possible - with the help of some knowledgeable
folk on this board of course!

Many thanks in advance,

\/era


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G'day Vera
Assuming that you have no test equipment, the basic method that would be
used by a serviceman would be to start with testing the element for
continuity and resistance to 'ground'. This can be done in situ but with the
lack of equipment you are stymied. The other option would be to remove the
element and take it to be tested. From the description of the fault it
sounds likely the element has failed and the first step would be to test it.
There also could be a problem in the wiring instead but once again you will
need some experience to check it, along with the equipment. I can only see 1
jpg of the bottom of the element/fan in the link.

 

[Sam Goldwasser]

No way to know for sure, but my guess is that the scorch marks are unrelated
and may just be normal discoloration over time.

You have the element removed, correct? Check it or have your buddy check
it with a multimeter. My guess is that it's now open circuit and needs to
be replaced even though it looks good.

(BTW, found the pics by changing the "101" to other numbers, you should have
provided explicit links.)

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|Filename: inside.jpg |
|Download: http://www.diybanter.com/attachment.php?attachmentid=101 |
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[James Sweet]

G'day Vera
Assuming that you have no test equipment, the basic method that would be
used by a serviceman would be to start with testing the element for
continuity and resistance to 'ground'. This can be done in situ but with the
lack of equipment you are stymied. The other option would be to remove the
element and take it to be tested. From the description of the fault it
sounds likely the element has failed and the first step would be to test it.
There also could be a problem in the wiring instead but once again you will
need some experience to check it, along with the equipment. I can only see 1
jpg of the bottom of the element/fan in the link.

--

Lack of test equipment shouldn't be an issue, one can pick up a suitable
multimeter for $10-$20, maybe less these days and it'll come in handy for
other things too.

 

[James Sweet]

No way to know for sure, but my guess is that the scorch marks are unrelated
and may just be normal discoloration over time.

You have the element removed, correct? Check it or have your buddy check
it with a multimeter. My guess is that it's now open circuit and needs to
be replaced even though it looks good.

If it tripped the circuit breaker I would suspect the element or the wiring
somewhere shorted to ground, in the process it may have burned out the
contacts on the thermostat or blown an internal fuse.