Burns are very painful & serious on snakes- it would be best to stop using this UTH until it's properly regulated, as there's just no way to "watch" it that will work.

Vet visit recommended for your snake, & btw. heat lamps need controlled too...at least get a lamp dimmer (aka rheostat) from the nearest hardware store...they are
not expensive. And assuming you have the means to accurately measure the temps. in the cage, test the dimmed lamp while you're home as to what setting (on the
dimmer) produces safe & adequate warmth. (You can buy a lamp dimmer already installed on an extension cord...that's the easiest, just plug your lamp into it & use
the control, usually a rotary dial or a slider, to adjust.)