Cooker thermo couple

[stav]

Hi I have a nelson spinflow cooker and last summer I changed the thermocouple on the left hand ring it has never been the same since and takes at least 30 seconds before you can letgo of the knob. The RHS and original takes about 5 seconds.

What have I done wrong(?) should there be some compound to help make it work where it screws in?

Also how do these things actually work?

Any suggestions gratefully received. Just thought I should have searched this first but I have typed it now.......sorry for being slack.

 

[Searush]

They are sealed units - or the expansion bit wouldn't work. Have you scewed the none flame end in correctly? Have you got the correct unit? I have replaced several flame failure devices on a range of different equipment using B&Q "universal" fittings & never had a problem. Good tip to use the B&Q stuff, they are cheap & you are not required to prove current CORGI membership to buy them.

 

[pete]

Thermocouple's By heating the hot junction a small electric current is produced that travels along the Thermocouple and through the nut to the electromagnetic valve.

A rough test is on turning off the burner there should be a short delay before the valve can be heard closing (click) anything over around 15 seconds is pretty good. (there are some appliances that automatically break this circuit with a microswitch linked to the gas tap but not many).

Most likely cause is that the burners flame is not catching the hot junction because of corrosion or the thermocouple being incorrectly positioned.

Make sure that the screwed end is clean and dry NO SEALANT

Take care not to kink the thermocouple as it relies on internal insulation and it can short circuit.

Some times you get a faulty new one.
Pete

 

[Billjratt]

You can measure the voltage with a meter (while heating) just to make sure it's not been damaged during initial installation, but the "no sealant" quote above is paramount, otherwise you will be insulating the connections. The time it takes makes it sound like an iffy connection to me, clean the fitting carefully and re-install.

 

[stav]

Thanks Guys that will give me something to look at. Clearly whilst it was just me sailing one ring was OK but with more crew more rings required!

 

[Alfie168]

Good tip to use the B&Q stuff, they are cheap & you are not required to prove current CORGI membership to buy them.

Most plumber merchants will sell anybody anything to do with gas, though a few won't. And these days 'one' is Gas Safe Registered not Corgi Registered.....mostly the same people, but working for Capita now.

Yes, no sealant, make sure thermocouple is firmly screwed into its contact point, and make sure the tip of the thermocouple is in a healthy looking flame. If that doesn't work the probability is a faulty thermocouple. It should not take longer than 8-10 sec for the flame to stay in.

Tim