What is the difference between the f.c.u & a.h.u & e.x host fan & split unit ?

Basically an AHU's short for Air Handling Unit supplies preconditioned air which is often ducted directly to or through a ceiling void to FCU's who in turn supply air to the user. Both AHU's and FCU's have air filtering, heating and cooling capabilites. An exhaust fan or extract fan takes used or unwanted air, smoke, fumes or odours out of a building. They can mostly be found on building roofs and are ducted to areas like toilets, starwells and offices etc, etc. A split unti is a specific design of airconditioning made up of a condenser and evaporator, the condenser is installed outside of a building often on the roof and the evaporator inside the building often on the wall of an office.

Dear Waleed

Mr Wayne sent you an excellent answer i agree with him.

thanks Mr.Wayne :)