If you’re a property developer, an architect or mechanical subcontractor, you should be aware that the landscape for HVAC equipment start-ups is about to change. You may be aware of some big changes coming up in the 2022 code cycle, but you might be surprised to learn that the typical mechanical start-up as we know it will soon be a thing of the past. Going forward, the CEC will require acceptance testing for most HVAC systems.

This means the days of an HVAC technician simply executing basic functional checks – or worse, simply making sure that the equipment powers on – are over. Now, the equipment technicians performing acceptance tests on nonresidential building projects must be trained and certified Mechanical ATTs (MATTs) who will be held to quality assurance standards, with penalties for non-conformance.

This means a higher standard has been set for installation and performance verification.

For building owners, this change should translate into greater confidence in (and higher reliability on) their building’s HVAC systems. Benefits include:

      • Less chance of disruption and escalating costs during operations phase; faulty equipment or improper programming can cost an owner tens of thousands of dollars if not properly addressed.
      • Higher chance of passing functional performance testing the first time (when commissioning is required by code), reducing the need for costly installer or commissioning revisits to fix issues and retest.
      • Greater likelihood that manufacturer defects normally missed by a rudimentary start-up procedure are caught early, while the equipment is under warranty for both parts and labor (This is especially true in cases where commissioning was elected not to be performed because it wasn’t required by code).
      • Better constructability on the part of mechanical installers and controls technicians through a standardized quality assurance protocol, especially when testing is conducted by a third party.
      • Catching potential equipment installation issues while the trades involved are still on-site (installers with an MATT on staff can certify their own work; however, there is an understanding that a certain number of their projects will be audited at random).

So why is this requirement just now being imposed?

Actually, the Building Energy Efficiency Standards have required acceptance testing for mechanical systems in nonresidential buildings since 2005. These tests would typically be performed by the installing technician. Since 2013, the Energy Standards specify that the CEC may require that only ATTs certified by approved Acceptance Test Technician Certification Providers (ATTCP) perform the required acceptance tests if certain requirements are met [Title 24, Part 1, Section 10-103.2(b)].

As of the 2022 code cycle (effective for projects permitted after January 1, 2023), these “may” statements have effectively become “will” statements, and this testing will be mandatory for virtually all mechanical systems regardless of project size. One might ask, “What are the exceptions?” For newly installed systems, there are virtually none.  Even certain modifications to existing systems – such as installation of new controls, cooling or heating coils or the addition of an economizer – will all require acceptance testing by a certified Mechanical ATT.

The following table contains examples of acceptance tests that will be required for certain HVAC system modifications:

These test procedures are rigorous, comprehensive, and usually require data collection while the unit is in full operation, blurring the lines between acceptance testing and commissioning. The main difference between the two is that commissioning is a holistic process that evaluates the HVAC system in its entirety, while acceptance testing mainly focuses on any newly installed components or specific functional capabilities of an HVAC system. These components/functions include economizers, fault detection and diagnostic systems and supply air temperature reset controls.

In summary, acceptance testing will be the new normal as of the 2022 code cycle. This testing:

      • Will apply to new equipment and systems installed in either new construction or retrofit applications
      • Will be performed by a certified acceptance test technician and
      • Must be submitted to the enforcement agency before a final occupancy permit can be granted.

VCA Green is well equipped for consultation and testing of these types of systems. For more information, contact Moe Fakih below.

Contributing Writer: Kontay Sexton, PE, CBCP

Moe Fakih, Principal








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