When it comes to cleaning windows, using room temperature water is generally recommended over hot or cold water. Hot water can cause the glass to expand rapidly, which may lead to cracking, especially if the windows are cold. Cold water, on the other hand, can be less effective at removing dirt and grime. Warmer water helps to break down stubborn stains and dirt more effectively without posing a risk to the windows. It also helps in dissolving any cleaning solutions or detergents used. However, it is essential to avoid using extremely hot water as it can still pose a risk to the glass. Ultimately, a mild temperature that is comfortable to the touch is the ideal choice for cleaning windows effectively and safely.