The function of the exhaust fan is to suck air out of the house.Cooling fan-cold air moved to replace hot air.
Do you need a ceiling fan in your house when you have an exhaust fan? Conversely, you need an exhaust fan when you have a ceiling fan? Well, do not make the mistake of confus … ing these two devices to be the same. Both these devices are fans. Yet, there is a huge difference between the functions and the uses of these two devices. The function of the exhaust fan is to suck air out of the house.  The centrifugal fan is one of the most widely used fans. Centrifugal fans are by far the most prevalent type of fan used in the HVAC industry today. They are usually cheaper than axial fans and simpler in construction. It is used in transporting gas or materials and in ventilation system for buildings. They are also used commonly in central heating/cooling systems. A centrifugal fan is a mechanical device for moving air or other gases. The terms blower and squirrel cage fan (because it looks like a hamster wheel) are frequently used as synonyms. There are many uses for the continuous flow of air or gas that industrial fans generate, including combustion, ventilation, aeration, particulate transport, exhaust, cooling, air-cleaning, and drying, to name a few.  The only difference between an intake and exhaust fan is the direction you install it in the case. If you look closely on the fan shroud (the part around the fan itself) you should notice an arrow on it which shows airflow direction. Fans generally can be used for both intake and exhaust. Now, your fans will have a CFM rating which is how much air they move per minute, higher is obviously more, there are two schools of thought on airflow. The most obvious difference between AC cooling fans and DC cooling fans is the type of electricity that they use. DC cooling fans use direct current (DC) electrical flows. This type of electrical flow can only move in one direction.  Well, do not make the mistake of confusing these two devices to be the same. Both these devices are fans. Yet, there is a huge difference between the functions and the uses of these two devices. The function of the exhaust fan is to suck air out of the house. Of course, the entire process will never be completely efficient because the windows are open and there always will be inflow and outflow of air. A turbo/fan can move air rapidly from one place to another (like a cooling fan-cold air moved to … replace hot air, or like a turbocharger-air through filter and induction manifold into cylinders) but with minimal (if any....) pressurisation, therefore you always end up with optimum air movement between two places. Posted on. by admin. Fan vs Blower. The fan is a mechanical device that is used to create a continuous flow of gas such as air. In any cooling system, which uses a gas as the working fluid, a fan is a compulsory unit which creates the flow of air through the system. It can be a simple ceiling fan used in households or an external cooling fan for internal combustion engines. When higher pressure is required blowers are used instead of fans.  Often, the terms fan and blower are used interchangeably, and are considered synonyms of each other. Although, both are similar in terms of circulating and supplying air, technically they are quite different from each other. The main difference between a fan and a blower is based on how the air is circulated. Generally, a fan is an electrical device that moves air, whereas a blower is a mechanical device that consists of a fan, and which channels the air from the fan and directs it to a specific location or point. Though, based on the amount of pressure they need in order to produce air, both are used accordingly. Blowers can move volumes of gas at a moderate pressure while fans move large amounts of gas at a low pressure. By definition, a fan is machine that is used to create flow within a fluid, such as air. No differnce in the fan itself, only in how it's used. An exhaust fan is just any fan used to move air away from an area, usually to the outside of a structure such as a computer, a room or a house. Geezer Geek · 6 years ago. Thumbs up. 
http://www.answers.com/Q/What_is_the_difference_between_extract_fan_and_exhaust_fan https://en.wikipedia.org/wiki/Centrifugal_fan https://en.wikipedia.org/wiki/Industrial_fan http://www.tomshardware.com/answers/id-1685007/airflow-cooling-intake-exhaust.html http://www.nmbtc.com/ac-fans/acdccooling/ http://www.answers.com/Q/Difference_between_Fan_and_Exhaust_fan http://www.differencebetween.com/difference-between-fan-and-vs-blower/ http://www.differencebetween.info/difference-between-fan-and-blower https://answers.yahoo.com/question/index?qid=20100111220116AAbE0Q6
difference between cooling fan and exhaust fan