Don't tell ANYONE I told you.
Disclaimer... Not only that, I take no, naughta, none, zip, zero responsibility of your personal safety with this information.
You can pull back the temperature sensor probe about an inch back. It will now read the temperture further back from the water and heat the water past 104. Your digital readout will no longer be accurate so you will want (NEED) a floating thermometer. Always check it prior to getting in!! The further back the probe is, the hotter your water will get. Be careful.
I do, in all honesty, hate recommending this. It can be dangerous and although you have heard this before bechman, I'm telling you again for the both of us. I couldn't imagine telling someone to do this and end up finding out someone got scalded or worse. Personally, 106 is as hot as I would go and even then, I would stay in no longer that 10-15 minutes. No kids in there at that temperature either OK? God, I sound like your Mother don't I?
Steve