Talmud Shabbat 18a states that
“It is forbidden to place grain in a water mill [on Erev Shabbat] unless it will be ground before nightfall. Why? Rabba said: Because it creates noise.” Rashi explains: “Because it makes noise and becomes known (avsha milta) on Shabbat, causing denigration [of Shabbat].”
Suppose that a home had a flood on Thursday. The insurance company evaluated the home Friday morning, opened the ceiling and placed giant noisy industrial blowers and fans to dry out the walls and ceiling and prevent mold. The assessor said that these loud units must remain on continuously through Shabbat, and beyond for several days, otherwise mold will build up quickly, and the home will not be insured.
In this situation, may the home owner leave these loud units on during Shabbat?