Neff oven thermostat problem

[johnatfarnham]

Does anybody know where a compatible oven thermostat can be obtained for a Neff double oven cooker. This is an old cooker and the E-Nr number 195.303 852 does not now register with any spares supplier. The top oven and grille within it ceased to work. From the temperature regulator switch there is a wire which runs to the thermostat which was an inch long device which had been solders to the end of this wire. From the other end of the thermostat another wire had been soldered and the end of this wire was connected to the oven heater element. I disonnected both ends of this wire and bypassed the thermostat to prove that the heater element was not faulty and indeed it worked which proves the thermostat is not working. But where, oh where, can I find another thermostat. The one that was in there was insulated with a rubber cover and then inserted into a small metal tube mounted on the back of the top of the oven This is a fan oven and the switch shows a temperature range up to 180C. Can anybody tell me where to find a replacement thermostat or at least a compatible one and if it is one that is just a probe how should it be wired.?
Johnatfarnham

 

[Specialist]

Was this on just one occasion where the fan struggled to start up or every time?I would of thought the fan would wait til the element heats up before kicking in fully?Just a thought

On the Majority of Fan ovens the fan comes on fully from the start of cooking.

 

[johnatfarnham]

Thanks again to the Specialist from Ammanford South. Yes I am wondering if it would be preferable to replace the fan and am at the moment trying to get it off. The problem is that the nut on the centre of the fan is extremely tight but with a bit of luck I will move it. Thank you also for the warning. I am extremely careful when working with electricity being well aware of the dangers. When I do work on the oven the electricity supply is completely isolated. Thanks again
Regards
John H

 

[Specialist]

Your welcome John, please let us know how you get on. Have you tried a little bit of WD40 on the nut & let it penetrate for a while ? You may find that a good pair of long nosed pliers holding the shaft is useful too.

 

[ringer]

To the Op (johnatfarnham) can you post the picture up here so we can all see? We know you solved your problem, but it would be good to get a look at the device in question - every day is a schoolday - and it might just be me looking inside an oven next time wondering what that device might be.

Whilst you've got the oven out John, how about a piccy or two of the components in question?

 

[johnatfarnham]

Thanks ringer. I will try and put in a photo of the micro temp but I have already tried twice without success. I know that I have learnt a great deal since I set out on this exercise Success !!! I also managed to find a 229C micro temp and have decided to change the fan which was being a bit erratic. All being well I will have a working oven by mid next week.

jo hnatfarn

 

[Marvo]

RS Components have a range of non-resettable thermal fuses here just in case your source has any problems. They come in a pack of 5 but they're so cheap it's not worth trying to buy them singularly. Maplin also have similar.

With regard to the nut on the fan shaft, it may well be a left-hand thread.

 

[johnatfarnham]

Hello Marvo in Cape Town and thanks. I have in fact bought a pack of 10 micro temps and they are cheap. And you are correct the nut on the fan was a left hand thread. I don't know whether you saw the last thread but I decided to change the fan unit as it was only working intermittently. The price £64 which I thought was reasonable but now you are going to tell me I could have bought it cheaper elsewhere !!
Regards
johnatfarnham

 

[Marvo]

The price £64 which I thought was reasonable but now you are going to tell me I could have bought it cheaper elsewhere !!

Lol, £64 sounds about right to me for a high temp fan unit.

So that's it, you're all up and running again. The only thing left to do is to get yourself a nice sized Turducken and give the oven a good old road-testing.

 

[johnatfarnham]

Hello the Specialist at Ammanford South. You will recall that after finding that what I thought was a thermostat in my Neff double over turned out to be a micro temp thermal cut-out. I have now fitted a new one and a new fan also and the oven is working. The problem which may have been a problem before of which I was not aware is that when the oven switch is set at 180c the oven temperature checked with an oven thermometer is at 190C. When it was at 160C the oven temperature registered 150C. Does this mean that oven thermostats are not that accurate to within 10% or so or does this signify that the thermostat might also need to be changed? My wife has been saying for some time that she didn't think the temperature was correct as her victoria sponge cakes did not seem to be cooking exactly as they should !!
Regards
johnatfarnham

 

[Specialist]

Hi John: Glad you've got it sorted out, Oven thermostats often have a +/- 10 to 15% leeway & it varies with Manufacturer. When you say Oven Thermostat, what type do you mean ? Is it a Digital with Flexible probe that fits in the oven while it's warming up or is it an Analogue 1 that you place in the oven, either before you start cooking or when the oven gets to temp?
1 thing that you could also do is to Wash the Door seal with warm water & a bit of washing up liquid, this can improve the sealing action.

 

[johnatfarnham]

Hello the Specialist at Ammanford and thank you again for your advice. The oven thermostat itself is a probe about 8 inches long and is fastened to clips vertically behind the back plate of the oven at the right hand side. This is the plate which covers the fan and heating element. The oven thermometer which I placed inside the oven on a shelf was one obtained from the hardware shop Dyas and is made in China for Tala. I wonder if this is not as accurate at it might be. It is a circular dial with the temperature registered in a clockwise direction from nil to 320C. I'm afraid that I wouldn't know whether this or the oven thermostat is digital or analogue. I will try washing the seals as you suggest and see how this affects the temperature. Replacement of top and bottom door seals looks as though they might be fairly easy as it looks as though it involves just the removal of two screws to remove the plates top and bottom which holds in the seals. However the two side seals look more involved and although the top and bottom ends of these seals are held in by the same plates that hold in the top and bottom seals the rest of the seal (a rubber flange) looks as though it is held in by the sides of the oven itself with no immediately apparent means of removing it to put in a new seal.
Regards
johnatfarnham

 

[Specialist]

Hi John: Your welcome to the advice mate, only glad we were able to help.
Your oven Thermometer is an Analogue type from what you described, i.e it has a pointer dial to indicate Temperature. A Digital Thermometer uses an LCD display for indication.
I would'nt rely on your Thermometer for accurate enough Temp readings to decide your oven Thermostat is faulty to be honest, especially as you have a fan oven.
Give the oven a try out for a week or so after cleaning the seals & you may well find that it's back to normal now you've replaced your faulty fan. Once you've given the seals a wipe over, put a small amount of Vegetable oil on a Rag & wipe the seals over with it, if you do that once a month or so it should keep the seals from degrading.
Anyway testing the oven is a good excuse for getting your missus to make you a few nice cakes:lol:.Please come back & let me know how you get on though.

 

[Marvo]

I wouldn't be surprised to see at least 10% inaccuracy with an oven thermostat even if it was brand new and functioning correctly. Apart from what Specialist suggested it might be worth checking the door closes fully against the seal, oven door hinges can lose their spring tension over time and a small gap can make large temperature swings.

 

[bugsy]

www.4neff.co.uk/Spares

Give em a whirl