Oven element - red hot

[marcus87]

I would expect a slight glow in a much darkened room. Red hot suggests it is designed for a lower voltage than the UK voltage, what did it specify when you bought it? It doesn't need to glow red hot in an oven, but it would were it a grill.

Stopping glowing as it reaches the thermostat setting is normal.

Thanks for the reply Harry,

The replacing element is 2300W, which is apparently compatible with the oven. I will try again later on when back home but i would say it definitely matches the colour of the grill element when heating up.

 

[jj4091]

If it did not glow with genuine Neff element but does with cheaper version & switches on & off as required to maintain the oven temperature then that suggests that perhaps the cheaper one just has less metal in the outer sheath. I would guess it is safe but may fail sooner than you would like.

 

[mattylad]

Can the op link to the online advert for the element?
So it can be confirmed as the correct one.

Although they could have sent the wrong one, the voltage and wattage is usually stamped on them.
Quite often they will get red hot, that's why they have guards over them.

 

[EFLImpudence]

There is nothing that can happen to make it get red hot if it is not supposed to be.

Also not quite red hot is still very hot.

 

[marcus87]

https://www.ransomspares.co.uk/parts/cookers-hobs/neff/compatible-fan-element/120674.htm This is the element i bought and my ovens number is b1430n0gb/02 which comes up as compatible.

 

[bernardgreen]

Written by an ""expert"" at Ransome Spares

The compatible Neff Fan Oven Element is a circular oven element designed to create resistance and radiate heat in compatible models of Bosch, Siemens, and Neff ovens and cookers. The round element has two turns to regulate the flow of electricity and heat up the oven.

"radiate heat" in a fan oven ? Fan ovens use hot air to cook the food , not radiant heat.

"two turns to regulate the flow of electricity" Wow...... would the flow be unregulated if there was only one turn ?.

 

[Harry Bloomfield]

There is nothing that can happen to make it get red hot if it is not supposed to be.

Also not quite red hot is still very hot.

Black hot is around 400C, glowing red hot is over 800C. An element running at 800C in an enclosed oven is unnecessary and if food is exposed to that it would be grilled.

 

[marcus87]

Thanks guys for the comments and observations, i feel i know abit more on ovens now.

So an update is that i tried cooking yesterday and... it worked fine. The oven is now warming up much faster than before. Once it reached the temperature it needed i didn't see the element getting hot again.

Regarding the cheap element i bought, i am not quite sure about it now. The element sent is this http://www.europart.co.uk/14-NF-29. Curiously it doesn't have B1430 as a compatible oven but B1432. By comparing the spec to a genuine replacement they appear to be the same. I will call them up to confirm.

By doing some more research on the topic, the previous element was not an original Neff either. Which is not a surprise as the property was previously a rental and not taken care of.

I am slowly coming to the conclusion that its probably a matter of time before the oven fails completely so might start looking around. Any recommendations on reasonably priced ovens?

 

[EFLImpudence]

Black hot is around 400C, glowing red hot is over 800C.

So? What colour is it at 750°C?
Metals vary.

An element running at 800C in an enclosed oven is unnecessary and if food is exposed to that it would be grilled.

It wouldn't be on for very long would it?

 

[JohnW2]

Black hot is around 400C, glowing red hot is over 800C.

Eh? 'Black hot' can surely be any temperature which is below that which results in the emission of visible light?

What are you suggesting happens between 400° and 800° - is that 'black', 'red', 'sky blue pink' or what?

Kind Regards, John

 

[Doug99]

"two turns to regulate the flow of electricity" Wow...... would the flow be unregulated if there was only one turn ?.

Two turns suggests the element length is longer than the single turn. The longer the length of an element, the higher the resistance to the electron flow. With a fixed 240v, by doubling the resistance you halve the current ie regulated the flow

A valid explanation to a customer who may be ignorant of Ohms Law

 

[EFLImpudence]

Yes, but the number of turns is irrelevant. Straight would be the same but it wouldn't fit.

 

[JohnW2]

Two turns suggests the element length is longer than the single turn. The longer the length of an element, the higher the resistance to the electron flow. With a fixed 240v, by doubling the resistance you halve the current ie regulated the flow

There are many assumptions behind that statement.

For example, halving the cross-sectional area of the wire as the conductor of the element would also result in roughly doubling the resistance, and halving the current, without any change in the length of the element.

Kind Regards, John

 

[Harry Bloomfield]

Eh? 'Black hot' can surely be any temperature which is below that which results in the emission of visible light?

What are you suggesting happens between 400° and 800° - is that 'black', 'red', 'sky blue pink' or what?

Obviously, as the temperature increases from 400 to 800 the element glows more and more, the spectrum of light emitted by the element becomes more visible. A tungsten filament at around 3000C emits light at around 3000K.

Its possible to judge the temperature of a metal with fair accuracy, simply by comparing its colour.

 

[JohnW2]

Obviously, as the temperature increases from 400 to 800 the element glows more and more, the spectrum of light emitted by the element becomes more visible. .... Its possible to judge the temperature of a metal with fair accuracy, simply by comparing its colour.

Indeed so - it was the assertion that "Black Heat" corresponds to 400°C which I was really commenting on.

A tungsten filament at around 3000C emits light at around 3000K.

Indeed. In fact, if the filament behaved as a true 'black body', it would emit light at 2727K (aka 3000°C)!

Kind Regards, John