i bought a element for the grill cos it was not working got that working then turned it on put it in a certain temp heats up to that temp then after 3-4 mins it cuts out till it cools down then it comes back on ,it happens to all temp on the grill i.e..50,100.200c..etc any help would be great i thought it could be the thermostat in the grill, model is Belling 317 WH 🙁