Control system verification
We check that every sensor reads correctly, every actuator moves when it’s told to, and the control sequences do what the engineer wrote.
When you need it
- A new building automation system has been installed and needs checking before turnover.
- The controls say one thing and the building does another.
- Equipment runs after hours, short-cycles or fights itself, such as heating and cooling at once.
- You’re upgrading controls or adding new equipment to an existing system.
What we do
Point-to-point checkout
We confirm every input and output: sensors read accurately against a calibrated reference, and every damper, valve and relay responds to its command.
Sequence testing
We put each system through its modes, including occupied, unoccupied, morning warm-up, economizer and alarms, and compare what happens with the written sequence.
Trend review
Where the system can log data, we review trends to catch problems that only show up over several days.
Report
We document what passed, what failed and what needs a programming or hardware fix.
What you receive
- Completed point-to-point verification sheets
- Functional test results for each sequence
- An issues log with recommended corrections
- Recommended trend logs and alarm settings
Questions
Isn’t this the controls contractor’s job?
The controls contractor does their own checkout. Independent verification confirms it, and catches the problems that are easy to miss when you’re checking your own work.
How does this relate to air balancing?
Balancing depends on the controls. VAV box minimums, fan speed control and damper positions all have to be right before airflow can be set, so the two are often done together.
Further reading
- Zoning a commercial building for HVAC
Learn how to group spaces into thermal zones that can be controlled properly, how zoning affects comfort and energy use, and the mistakes that cause persistent hot and cold complaints.
- Economizers: types, controls and common failures
Learn the types of economizers, how high-limit controls decide when to use outdoor air for cooling, and how to find and fix the failures that quietly waste energy.
- Mixing boxes, stratification and freeze protection
Learn why air streams fail to mix in air handlers, how this leads to frozen coils and freezestat trips, and the design, control and operating practices that prevent it.
- VAV box types and selection
Learn the main VAV terminal unit types, how to choose between them, and how to size boxes for controllability, low noise and efficient minimum airflows.
- Control valve selection and authority
Learn how valve authority, flow characteristics and proper sizing determine whether a coil controls smoothly, and how to choose between valve types for HVAC systems.
- Low delta-T syndrome and how to fix it
Learn why chilled water plants often return water colder than designed, what that costs in pump and chiller capacity, and how to find and fix the root causes.
Related services
Also in testing, adjusting and balancing: Air balancing (TAB), Water balancing (hydronic), Duct leakage testing, Residential air balancing.
Get a quote for control system verification
Tell us about the building and what you need. We’ll be in touch within one hour.