A question about Whirlpool - 30" Self-Cleaning Freestanding Electric R

Front left burner was going but not alternating off to on as usual, and as we got the repair man he seems to have fixed it and now it’s pulsating again, but it takes about 30 seconds in intervals. First hot, then it goes off for 30 seconds, then it comes back again. Is the 30 seconds interval normal time? When my wife called the technician again to enquire, he said the settings are in the manufacturer and can’t be changed.. it either works or it doesn’t. เว็บสล็อตค่ายนอกดีที่สุด