Grill won't stay lit

I have the same model and have the same problem, sometimes it is ok and others it goes out. I also suspect the thermocouple, possibly it is not being heated enough for whatever reason. It seems worse after grilling anything which splashes fat about like sausages.  I would be interested in further comments.

peedee

probably need the oven removing to get to thermocouple.

https://www.inter-spares.co.uk/thetford/thetford-cooker-oven-spare-parts/ck13933-aspire/grill-thermocouple-en-3.html?gclid=Cj0KCQjw5s3cBRCAARIsAB8ZjU3O-gV-pWA-HK-lixtwnVuYijBkdKWtYSoDv2PnlJsgVSOwIgBrLLgaAoyCEALw_wcB

is the thermocouple In the flame, if not would stop it working. light as normal and hold in knob and look at flame and see if it is. you could always bend bracket a little to get the full effect of the flame. when cooled.

Is it one that needs the hob lid to be up? If so, make sure it's pushed back properly.

My views mirror LL's but I wouldn't try bending the thermocouple. I think it is quite likely to break. My gas is off at the moment and motorhome laid up. Next time I use it I'll do as LL suggest before doing anything further.

Don't think there is a safety interlock on the hob lid but will check that just in case.

peedee

Same model and same problem. Gas thermocouple replaced - about £18 if I recall.

peedee. I should have said bend bracket that thermocouple was fastened to, not the tc itself

The thermocouple protrudes from the grill back plate into the rear gas jet. There is no bracket to bend. I suspect if this last jet is not performing as it should this is the cause of the problems being experienced. Alternatively, is the probe of the thermocouple being splashed with fat/burnt residue and effecting it's performance. Perhaps a clean up with an old tooth brush is worth a try.

peedee

Thermocouples tend to become fragile over time. Bending then will very likely end in tears.

Here’s a cure which has never failed me over the years. Mix detergent and water on your washing up brush and give the burner including the thermocouple, a firm but not brutal scrub. Rinse the brush and repeat with clean water. It may be a little slower to light while still wet, but once going it’ll probably stay on when you release the knob and work normally after that.

The method will work on any burner, so long as the thermocouple hasn’t really failed. The only time we’ve ever had a thermocouple fail was decades ago, on a central heating boiler which had been serviced recently - quite likely weakening the thermocouple while doing so.

Forget all lid advice, if the interlock is stopping gas then it won’t light in the first place.

We recently had a problem with the grill in our Thetford Aspire 2 cooker (fitted in our 2015 Swift Challenger).  It’s always been difficult to light but, once lit, has stayed alight.  Maybe there’s a general problem with Thetford grills?  Anyway, we went away in June and somehow the grill burner had dropped down from the fixing at the front.  I discovered it when I was using it, and the burner caught on the food as I put the pan back under.  I spoke to our dealer and they preferred to have the caravan in the workshop to check it out, for safety’s sake, and were willing to replace the whole cooker under warranty if it were necessary.  It turned out to be a simple replacement of the fixing, with no other damage to the burner.

A long reply, apparently irrelevant, but I just wonder if the OP’s oven is still under warranty, and whether it’s safe to attempt to repair gas appliances oneself?

Mine does the same. Has done since new. Reported at both services and always performs flawlessly in the dealership. 

Cleaning a thermocouple has no effect, it can be covered in stuff and still work. Cleaning the burner is a  good idea if the flame cone does not reach the thermocouple.

I have noticed that a slight draught causes it to go out, even just walking past when it is on, but it does just go out on its own occasionally. 

My thermocouple is right in the tip of the blue cone, glows red hot so position is not the issue. 

Probably just poor design but Thetford are not going to own up. Some have had the controller changed and report improvement.