Commercial Heating and Cooling
Roof Top units are the method of choice for heating & cooling commercial buildings.
Another draw back is the units are out of sight and can be easily neglected. It is surprising the number of no heat calls that I have gone on and the tenants have no idea where the heat comes. What do they think, the place is heated by magic! When I ask, "When was the last time the air filter was changed?" and their response is "What filter?" I know it's going to get messy and go grab my overalls, mask and gloves.
The air filter should be changed as required, for most retail and office space, that is once every 3 months. Some places may require more or less frequent filter changes. In the spring, before summer starts, the cooling operation should be tested. Condenser coil cleaned, air filter replaced and any motor that require it should be lubricated. The Contactor coil should be checked for any burn marks or overheating. An overheated or damaged contactor can stick and fry the winding in the compressor