How to adjust temp on on demand water heater

[retiredSC]

I just bought a 2018 Airstream Interstate Grand Tour, and unfortunately it came with zero manuals on all the systems. It has the on demand hot water system but there is no panel to set the desired temperature for the water heater to operate at. We had a 2021 Flying Cloud that had the panel in the bathroom but the Interstate doesn’t have one. When taking a shower, the water is scalding hot, and very difficult to set with the faucet. Is there a way to adjust the temperature on these units?

[GCinSC2]

Sorry, don't own one so no first hand experience. But I have complied many factory service manuals from online sources mfgr's and one good source for manuals in general https://myrvworks.com/manuals/ and Airstream manuals https://www.airstream.com/owners/man.../tc/year/2018/

Good luck

Gary