I use very hot water on woolen knitted stuff all the time. Hot water helps remove body oils or other oils that may accumulate on the item.
I think you say that because you worry about the item fulling (shrinking). It takes three components to full a woolen item: A change in water temp, a change in the water pH, and agitation.
Soak the woolen item in hot water into which a small amount of dish soap or shampoo is dissolved until the water is lukewarm. Remove item, drain water, refill with hot water to which a little white vinegar is added (helps remove residual soap). Soak until water is lukewarm. Remove item, drain water, refill with hot water to which a little hair conditioner has been added. Soak item again till water is lukewarm. Drain water. Gently squeeze item until most of the water is out. Roll item up in a thick towel and step on it to help squeeze out the rest of the water.
Lay item on absorbent surface and block. Let dry.
Large items can be washed in the washing machine following the same directions as above. One can spin the water out between each step, but don’t let the item be agitated. Just soaked and spun out. Then blocked.
Agitation is more of a concern than water temperature.