I'm just wondering what other companies are doing when they clean the coils on a RTU. Seems like we usually use compressed air on the condenser coil and some leave in coil cleaner on the evaporate coil. If there is any really bad we will first use a brush.
I'm just a first year that has not gone to school yet for HVAC but it seems to me that we should be using coil cleaner and water. We use air mainly due to the fact the we don't often see hose bibs on the roofs.