Oven not working as expected.

[Mymla]

Hi everyone,

Hey guys. Looking for some help with an oven that doesn't work. I have tried to get help elsewhere but the problem still persists no matter what I try. Any help or suggestions would be much appreciated.


I have an AEG competence b1180-4 (Pnc= 944 185 042) which was working fine for a couple of years before two days ago it stopped working.

When I switch it on at the wall socket the clock lights up and displays the time set function (which it never used to do) prompting me to set the time. After this if the oven is switched to one of the cooking modes (Grill, fan etc) the little red light on the left lights up as expected (however is sometimes flickering). However when the temperature dial is set the other red light (to tell if it has reached the set temperature) does not come on as expected and the oven does not start heating up. The main fan does not come on (however the cooling fan can be heard switching on an off intermittently). The grill does not heat up on that setting and the light inside does not come on.

I have tried the following:

1. Bypassed the clock entirely and the exact problem still persists.
2. Bypassed the little thermostat near the fan
3. bypassed the ZN limiter

Still the exact same problem...

The selector switch looks ok from the outside.


A more detailed description of what I have done and the help I have received so far along with photos can be found in this forum post.
http://www.ukwhitegoods.co.uk/forumsphpbb3/aeg-oven-not-working-correctly-t93969-15.html


Thanks for any help in advance

 

[davenn]

bypassed the ZN limiter

dunno what that is ???

if it isn't the main rheostat, then you should be replacing the rheostat ....

I don't know who/what on that other place you are since I didn't see your nickname there ???

I did see a link to one pic that showed an overheated/burnt wire in a termination .... if that is yours, have you fixed that ?

 

[Minder]

On recent repairs to both full size ovens and toaster ovens, it has been a small relay that switches the elements on, they are small PCCT relays that are Supposed to carry the required current but I am not surprised they failed in light of the size.
A possibility.
M.

 

[Mymla]

Thanks for replying guys!

Davenn: The Zn limiter according to that website is the small blue rubber thing that was burnt. Bypassed it but same issue. By rheostat, do you mean the temperature setting knob? Sorry I'm new to oven mechanics. I'm Steve on the other site by the way.

Minder: where might I locate that relay and how would I know if it has gone.

 

[davenn]

Bypassed it but same issue. By rheostat, do you mean the temperature setting knob?

Yes

 

[davenn]

it has been a small relay that switches the elements on, they are small PCCT relays that are Supposed to carry the required current

never ever seen those in ovens

 

[Mymla]

Would there be a safe way to temporarily bypass that to see it it is the culprit?

 

[Mymla]

If I just join the wires going into it then does that just mean its set to maximum temp? That would do to test it. Once I know what's causing it I'll buy a new one

 

[Bluejets]

Check that the clock has not switched to automatic.

 

[Mymla]

Check that the clock has not switched to automatic.

I have bypassed the clock entirely.

 

[davenn]

If I just join the wires going into it then does that just mean its set to maximum temp?

yes

so just leave it connected long enough to see that the element is warming up

 

[Minder]

never ever seen those in ovens

Replaced a few in full sized stoves here, the relays switches the oven elements.
M.

 

[davenn]

Replaced a few in full sized stoves here, the relays switches the oven elements.
M.

WOW never seen that here

 

[Minder]

The last was a high end toaster oven, replacement miniature relay was $1.50 from ebay.
Switching 1800W !!
https://www.amazon.ca/Breville-BOV8...d=1497638838&sr=8-7&keywords=breville+toaster
As typical of these kind of items, the manufacturer will not sell a new board as they say it is not consumer replaceable and it has to be shipped in for repair.
M.

 

[Mymla]

Tried bypassing that rheostat (temp dial) but still no joy. Such a weird problem. The only thing left I haven't tried is the selector switch but that has so many wires going into it i'm afraid to try and bypass it.

 

[Minder]

I would wager that is also a relay somewhere, the alternative switching device would be a SSR and so far they are few and far between that I have seen.
On most they are on the timer/clock/setting panel.
M.

 

[Mymla]

I have bypassed the clock so I can't be anything there. Pretty much everything is bypassed now except for the selector switch which looks ok on the outside but maybe it could be worn out on the inside

 

[Minder]

Can you see any printed circuit board behind the top panel?
Is there any small PCCT relays visible?
Usually small black or white cubes.
M.

 

[Mymla]

Behind the top panel as in where the clock is? or towards the back?

Thanks for the help!

 

[Minder]

I am not familiar with that particular oven, but it has been my experience the CCT board is behind the top panel shown with a clock/timer etc.
M.