SAMARTH AIR TECH PVT. LTD. Hot Exhaust Fans offered are used to pull excess moisture and unwanted doors out of a particular room or area. They are commonly found in bathrooms and kitchens, where moisture can build up due to activities such as showering, washing, or cooking. They are installed in kitchens and bathrooms due to the purpose of those rooms and the effect they have on the air quality of your home. Hot Exhaust Fans work by sucking hot or humid air out of a small, localized area, allowing fresh air to enter from elsewhere in order to replace it.