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For most organizations, one of the most impactful aspects of their facility management and operations is their HVAC systems and the associated energy costs. Given that, it is always a front of mind issue for facility managers, Business Administrators and other leaders. When you realize that 50-75% of an organizations utility bill is due to the HVAC system, it becomes a really important aspect to understand.
Early in my career, I had a mechanical engineer tell me that the only thing I needed to know about HVAC systems is that they “suck and blow.” In essence, that is accurate…they suck air in through return vents and blow it back out through supply access points. Seems pretty simple. But technology, energy codes, environmental considerations and desire for efficiency has changed the landscape of the HVAC industry.
Below are trends that every facility owner, facility manager and organizational leader responsible for the stewarding of their facility should be aware of.
Building Code Changes – Depending on what state you are in, some of these code items are currently mandatory while in others, it is coming:
- Primary entrance doors to access rooms that are over 3,000 SF must have a vestibule (sanctuaries, gathering, large classrooms, etc.). Some people call this an “air/light lock”…but it is basically the requirement to have 2 sets of doors with the vestibule in between the sets of doors for any assembly space over 3,000 SF
- Demand control ventilation, using CO2 sensors that control and provide increase outdoor air for high occupancy spaces (i.e. worship, gathering large classrooms, etc). If you are building a new assembly space, you have to add CO2 sensors that will engage the fresh air intake portion of your system when CO2 leaves reach a certain level.
Open Protocol – The days of proprietary control systems is rapidly coming to a close thanks in part to the introduction and development of open protocol systems such as LON and BACnet:
LON – Local Operating Network – was one of the pioneers in this space, but its use is being overshadowed with the introduction and rapid adoption of BACnet
BACnet – Building Automation Control Network – has become the most popular open protocol and is widely supported by developers and ASHRAE (American Society of Heating, Refrigerating, and Air-Conditioning Engineers)
Integration – You may wonder why “Open Protocol” is a trend on this list. The reason this is so critical is due to what is called the Internet of Things (IoT). One definition is: “The Internet of Things (IoT) is a system of interrelated computing devices, mechanical and digital machines, objects, animals or people that are provided with unique identifiers and the ability to transfer data over a network without requiring human-to-human or human-to-computer interaction.” Things talking to things. In the HVAC world, it is thermostats talking to controllers and JACE’s. It is BACnet compatible systems talking to your Event Scheduling Software. The open protocol systems allow for more freedom in developing “things” that talk to each other. More on this another time.
Wireless – This should be surprise given all the wireless applications we use in nearly every aspect of our lives. However…in the world of HVAC, wireless is NOT synonymous with Wi-Fi. Let me explain.
- Wi-Fi – is a technology that allows electronic devices to connect to a wireless LAN (WLAN) network. The Wi-Fi Alliance defines Wi-Fi as any “wireless local area network” (WLAN) product based on the Institute of Electrical and Electronics Engineers’ (IEEE) 802.11 standards. In short, it is what most of us use to connect to the internet when at work, home or a coffee shop.
- ZigBee – Wireless language for device connectivity. ZigBee is an IEEE 802.15.4-based specification for a suite of high-level communication protocols used to create personal area networks with small, low-power digital radios. It Is NOT Wi-Fi.
- BACnet systems offer wireless components that use the BACnet protocol
VRV/VRF –Variable Refrigerant Volume (Flow) – The simplest example of this technology is what most of us might refer to a “mini-split” system. But this category of HVAC units is far more encompassing than that and it is gaining popularity and acceptance at an increasing rate. VRF is an HVAC technology invented in Japan by the Daikin company in 1982. Like ductless mini-splits VRFs use refrigerant as the cooling and heating medium. This refrigerant is conditioned by a single outdoor condensing unit, and is circulated within the building to multiple fan-coil units (FCUs). This technology is on the move and will do so for years to come.
HVAC vs. AVLA (Audio, Video, Lighting and Acoustics) – if you have a sound system, then you know that in many cases the AVLA system is the tail that wages many facility and budget decisions. I am not being critical. We have just come to expect a higher level of sound in our spaces than just that of a megaphone or and AM radio sounding system. With this requirement comes several considerations in the ambient noise that can be caused by the HVAC systems. As such, attention must be given to:
- Vibration of units on the roof or in close proximity
- Installation of isolation curbs to assist in the reduction of vibration
- Air velocity…which incorporates fan speeds, duct size, duct location, register locations and design/shape.
- Larger lined ducts
- How to address “haze”. If your church uses haze, then you know what I mean. If you do not use haze, then just ignore this. The particulate size of the haze can impact the “duct sensors” in your return air vents thus making the system think there is smoke, triggering the fire alarm…OOPS!
Refrigerant is changing…AGAIN!!! – Yep…that is right! Once we had R-22 Freon that was phased out (although you can still get it) and replaced with R-410A as it was better for the environment. This is the current refrigerant…but only until 2025 when ASHRAE will introduce a new format referred to as a “2L Flammable Refrigerant” (Name TBD). Do you ever feel like the HVAC industry has learned a lesson from the computer industry? They change to “operation system” every so often making the old systems obsolete. BROTHER!
Residential Thermostats – How many of you have bought a Nest or other wireless stat for your home. They are pretty cool and in some cases the will work in a small commercial setting. But before you rush out to Lowes to get your wireless stat, here are some considerations:
- Multiple Stages of Heating and Cooling
- Size of the building
- Number of buildings
- Ability of occupants to adjust temperature
- Variations in weekly/annual usage
- Type and age of the HVAC equipment
*These are all factors that need to be considered and vetted before investing in these residential options.
These 8 trends represent areas of consideration that you, as the steward of your facilities, must become familiar with and determine the best application of them for your facility.