no problems here.
We heat the van at night.
Hot solution is not a problem either with the Powermatic's 231,000 BTU kero fired burner.
On really cold days, we make sure everything is ready to rock and roll before the solution line is taken in and the pump turned on.
Once the water is flowing and hot, freeze ups aren't an issue if the wand stops for a short time to move or tab furniture.
The coldest temp we've worked in was 12 below.
Though I hesitate to take the van out in those temps
..L.T.A.