Hilux 4x4 Forum

I'm having a problem with my oven ... Defy 600s slimline

Oven does not switch off.

When i put the switch on 0 marker, i can feel it click into the off position, but the light stays on.
I thought thermo might be bust, but if anything, if that the cause it should default to not go on at all?

I read up on some problems with this stoves, and found this article where people saying stove does not go on.
Apparently there is a little switch hidden at the back, that can be reset with paper clip and oven works again...
Here is the pic of the switch...

https://mybroadband.co.za/vb/showthread ... st21767003

My switched was bypassed by someone who worked on it before i bought it.
What the purpose of this switch? Could the bypass of it be the cause of my problem.
Don't wanna buy oven control switch, and this little unknown switch is the problem.

Shaakir the function of the thermostat is to regulate the temp of the oven by constantly switching the elements in the oven on and off .
By bypassing the thermostat switch,the elements will continue to heat the oven up and thus there is no way of having the oven operate at a preset required temperature.
I suggest you have the thermostat replaced by a suitably qualified technician.

What Tony says is correct. A faulty thermostat that does not register the increasing heat or fails to break the circuit when the desired heat is reached, will keep the elements burning.

I am not familiar with your unit at all, but I assume it's an under-counter oven and since the cabinet or "carcass" that it's mounted in is generally made of wood, the escaping heat into that cavity has to be evacuated so as to prevent a fire hazard. This is normally achieved with a built in fan (not the internal convection fan) that draws cool air into the cavity from the bottom front of the unit and dispels the hot air from the cavity at the top front of the unit (the vent holes are often concealed behind the closed oven door but are 'outside' of the door seal. One will usually hear the fan start up some time after the oven has been turned on and continue running for some time after the oven is off until it has sufficiently cooled. This vent fan is also controlled by a thermo switch somewhere at the back of the unit and I'm wondering if the one you see is not that one - (the one in the pic on the link looks more like it could be the oven thermostat switch judging by it's position inside the insulation material. If that has been bridged, the thermostat cannot work as it should and the circuit is kept closed irrespective.

You can remove the bridge and see what happens but I suspect that the thermostat will need replacing.

SO i did some digging into this little magic switch.
It's called a thermal fuse. It's purpose is to "pop" when the oven gets too hot. This may be for various reasons. Some ovens have self cleaning option where it goes above normal max temps , and sometime the thermal fuse mistakes this for dangerous event and blows.

In my case, i suspect it the fact that the oven door does not close completely. Springs need to be replaced. This allows warm air to escape making the element work overtime, thus popping the fuse.

Before i reconnected the thermal fuse, i let the stove run at 70degrees, and saw the oven light go on and off. Which means the thermostat is still doing it's job. On the oven control switch (70th satchwell switch) was a little screw that looked like was a temp setting screw. I opened the switch, and saw it control the placement of contacts. I turned it a bit, and switch working as it should. Light goes off on 0 position and indicator and oven light goes on when i turn it on.

I then reconnected the thermal fuse for safety, and stove was dead. Pressed the reset button with a toothpick, heard the little click, and stove working again. Put it on 180... watched it indicator light switched on and off telling thermostat doing it's job.

Next to replace door springs to avoid thermal fuse popping again.

Cool bananas!