Controls and Building Automation

Refrigeration and HVAC controls, followed through a second-year apprentice at an HVAC-R contractor in Kitchener: control loops, differentials and PID action; temperature sensors and how to check them; thermostats, pressure controls and pump-down; safety controls and lockouts; defrost control; walk-in and display case controllers; electronic, inverter and communicating equipment; economizers and ventilation control under the NECB and Ontario's energy rules; building automation points, sequences and overrides; BACnet, Modbus, RS-485 wiring and defensive cybersecurity; trending, alarms and commissioning; and a systematic method for control calls.

RAC-230 12 lessons · 3 h 33 min ▶ Video lessons coming soon

Offered by HSM University · Refrigeration and Air Conditioning

This is the Canadian version of this course. See the American version.

What you'll learn

Describe the parts of open and closed control loops, set two-position differentials that protect compressors from short cycling, and recognize the effects of proportional, integral and derivative action
Explain how bimetal elements, thermostatic bulbs, thermistors, RTDs and thermocouples sense temperature, and check sensors and their wiring against a calibrated reference
Set up thermostats, liquid line solenoids, low-pressure controls, crankcase heaters, condenser fan cycling and staging for pump-down and normal operation
Explain the purpose, wiring, settings and reset types of high- and low-pressure, oil, freeze, flow and motor safety controls, and troubleshoot a tripped safety without defeating it
Set defrost initiation, termination, fail-safe, drip and fan delay settings for walk-ins and display cases, and diagnose defrost faults on refrigeration systems and heat pumps
Install, program and test electronic walk-in and display case controllers, including probes, door switches, anti-sweat heaters, alarms and logging
Use fault codes, test modes and service data on integrated, inverter and communicating equipment, check pressure transducers and troubleshoot communication faults safely
Check minimum ventilation, demand-controlled ventilation and economizer dampers, sensors and changeover settings, and calculate the outdoor air fraction from temperatures
Describe the structure of a building automation system, its point types, sequences of operation, schedules and overrides, and use command and status to find faults
Explain how BACnet and Modbus devices communicate, install and check RS-485 field buses, and apply basic defensive cybersecurity practices to building systems
Collect and read trend data, apply simple fault detection rules, manage alarms so people act on them and take part in commissioning and functional testing
Apply a systematic control troubleshooting method that finds the disagreement between what a control believes and what the equipment is doing, and document the repair

Course content

12 lessons · 3 h 33 min total · final exam

1 Control fundamentals: loops, differentials and PID 21 min · quiz
2 Temperature sensors and how to check them 19 min · quiz
3 Operating controls: thermostats, pressure controls and pump-down 17 min · quiz
4 Safety controls and lockouts 18 min · quiz
5 Defrost control 17 min · quiz
6 Walk-in and display case controllers 17 min · quiz
7 Electronic and communicating HVAC controls 18 min · quiz
8 Economizers and ventilation control 17 min · quiz
9 Building automation fundamentals 17 min · quiz
10 BAS networks, protocols and cybersecurity 18 min · quiz
11 Trending, alarms and commissioning 17 min · quiz
12 Control troubleshooting: the capstone calls 17 min · quiz
E Final exam 20 questions

Requirements

RAC-130 Electrical Fundamentals for HVAC-R

Recommended background. You can start any course at any time.