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Johnny B Good Johnny B Good is offline
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Default Replace Bosch Oven Light - GGrrrr

On Mon, 26 Apr 2021 10:20:16 +0100, thescullster wrote:

Hi all

Not sure how common a problem this is or whether it is a design flaw.

Whenever I need to replace the oven light, the glass cover that protects
the bulb is always seized in, probably something to do with cycling
temperatures mixed with vapourised food particles.


That was my impression too. :-(

Anyhow, this time it seems to be worse than ever. Either that or I am
getting weaker which is highly likely.


Yep! That too


The glass cover which is about 2-1/2" diameter has a thread on it, so
the whole thing screws into a plate at the top of the oven. It doesn't
screw into the oven casing itself but rather a plate above this which
moves a bit when turning the glass cover (this is not really relevant
but a detail which seems strange to me).


It's a stainless sheet steel construction with a hole punched out and
the edges formed into a single screw thread matching that of the glass
cover. It minimises the area of contact with the glass in the hope of
minimising the strength of the 'glue bond line' that forms over the years
of utter neglect between actual lamp failures.


Unfortunately, the glass cover is surrounded by heating element so it is
not possible to get one of those rubber strap type oil filter remover
gizmos on it.

Does anyone have any words of wisdom on methods to get the glass cover
to unscrew please?
And yes, according to the instruction manual I am turning the thing the
right way (although I have tried "tightening" it in an attempt to free
it off).


Reading this reminded me about the last time I was forced to remove
these covers in order to replace a lamp some two or three years back.
Thus reminded that the time to give them their annual (biennual?) routine
extraction/clean up/insertion cycle was now probably way overdue, I
decided to check the lamp fixtures in our Bosch double oven to see
whether the great care I had taken to NOT over-tighten both covers _and_
lamps had actually done some good.

Whilst the covers _and_ the lamps seemed a bit tight initially, I _was_
able to extract them without much difficulty (at least to the extent of
thoughts "There MUST be a special tool for this!" not springing to mind
like the last time I did this job).

The main fan assisted oven which only gets used one or twice a year
(Christmas time) was, as I expected, the easiest to check out (but still
surprisingly tight to start with). That lamp is tucked away into the
upper right hand back corner, suitably angled to illuminate the oven
interior. I guess this helps minimise the inevitable build up of crud as
well as make it a little easier to get a hand grip on the cover.

The upper toaster/oven, otoh, locates the lamp dead centre in its roof
in amongst the toaster elements just like you described. This is the one
that sees frequent and regular use so I was expecting this to prove a
little harder to deal with. It was, but not enough to consider spending
over a fiver on a "Use once every five years" lamp cover extraction aid.

The glass cover, unlike that of the main oven cover glass, was in a far
from pristine state, so I landed up making a near futile attempt to clean
off the brown varnish coating from the textured surface moulded into the
glass (it really does need the use of a small wire brush to do this
justice).

However, a 100% or so boost in light transmission justifies the ten
minutes or so I'd spent on removing something like 50% or so of this
light absorbent coating (especially as I'm using a 25W pygmy oven lamp
rather than an over-priced Bosch 40W original - the main oven meanwhile,
remains blessed with a full fat 40W replacement).

The cheaper 15W pygmy oven lamps will still fit the Bosch oven lamp
holders so are worth having in the kitchen spares drawer as cheap 'get
you by spare'. Even better if you can spot any of these in the 25W rating
since the reduction in light output is far less than that of the more
commonly available 15W lamps (but any amount of illumination is better
than none at all).

The key to saving on the expense of a 'special extraction tool' in this
case, would appear to be adding a reminder to every new kitchen calendar
you buy, to check them over once a year (November seems as good a choice
of month as any). And, of course, not forgetting to take great care to
not over-tighten the covers or the lamps when re-fitting them.

--
Johnny B Good