As is the case with just about all HVAC equipment, central air conditioning systems are powered and contorted by electricity. Single and multistage low voltage thermostats energize line voltage devices such as single and multistage compressors, condenser fan motors, and evaporator fan motors. Some systems have electronic zoning that input thermostat information, and output commands to the various pieces of equipment that makes that equipment to run at various capacities and fan speeds. Today we are seeing energy saving ECM motors that have built in computer electronics that very precisely control air flow through the equipment. And for commercial applications, we also deal with controls that allow air conditioners to run both summer and winter.
We offer two classes in air condition and heat pump controls. During the "Air Conditioning Controls" class, we will examine electrical control circuits that range from simple single stage compressor, single speed fan systems all the way up to complex, zone controlled, multistage compressor(s), multi-speed and variable speed air handling equipment.
During the "Heat Pump Controls" class, we will take the information learned in the "Air Conditioning Controls" class several steps further and examine the additional controls found in heat pump systems. We will get to know how the reversing valve is energized, how the defrost timer works and what events can turn off the defrost cycle. We will understand outdoor thermostats, why they are needed, and how to calculate the set-points. We will also get information on control strategies that allow us to control hydronic heating systems with coils in the air handlers for the every popular hydro-air heat pump configuration.
You will understand the wiring of these systems and you will develop troubleshooting skills that will allow you to: find failed electrical components, find open circuits with bad connections and broken wires, understand how to test ECM motors, equipment that was wired wrong, and equipment that has direct shorts. This is the technology you need when your faced with real problems in the field.