Oven Not Working after replacing fan.

I bought a secondhand cooker for my sister.

After about 4 weeks she told me the fan never worked and the oven took a long time to cook and she hasnt used the cooker after the first time, only the grill.

I found it strange that a fan not working should alter the function of the oven too much but took her at her word.

I ordered the fan from this site and on monday fitted it.

the fan was not identical but the screw holes and general size meant it fitted, but the blades for attaching wires to were located differently meaning I was unsure which way to put the wires onto the new fan.

I took both fans to the shop that sold the cooker and he said that it didnt matter which way. I found it strange that would be the case as I kind of figured at the very least the direction of fan spin would differ. I took his advice anyway.

Upon fitting the fan , shortly after turning on the cooker it tripped what I think was an RCD. I’m not at my sisters now and so cannot look to check exactly what it was that tripped but it was a larger switch to the side of the smaller ones for individual circuits.

I changed the polarity of the wires powering the fan, still tripping :con:

I opened up the back and checked things and noticed that one of the 3 screws holding the fan attached to the back of the oven was not secure . After securing it properly and replacing the back the RCD no longer tripped. 😀 . I assumed the fan not being secured made a fault involving the earth.

Unfortunately , the oven does not heat up.

I questioned my sister to make sure she wasn’t misremembering etc as to the oven heating before but am pretty sure it did work. the fact of her saying it heated slowly makes me wonder if the element was failing already.

Obviously I am wondering what is wrong with it and how it happened. I spoke to the shop who sold it and they are saying I must have damaged the element and that if i bring the element in they will test it. I guess I will do this although I’m slightly hesitant after possibly having caused the damage in the first place.

I said this to the shop and noted the fan was faulty in the first place and Im a bit wary of now tackling the element change in the hope they would do the replacement. Because its 4 weeks after the sale with no warranty implied anyway I don’t really feel like I have much in the way of rights over this. They’ve said to take photos of the wiring at the back.

If it is the element how might that have happened. I was pretty careful with the fan change and taking the fan cover off etc to not damage the element but perhaps they are very fragile.

I did notice there was what I assume is a thermostat in the oven in the vicinity. I did wonder if that had failed . When they fail do they fail open circuit or closed or both?