Variable Refrigerant Flow (VRF) technology has been commonly used throughout the world for the past three decades, particularly in Asia and Europe. Increased energy efficiency, flexibility and the potential to offer a quick return on investment have been some of the key drivers for its new-found popularity in the United States since the turn of the century.
Thus, in this blog post, we want to inform you about what a VRF system is, how it works, and VRF advantages. By the end, you’ll learn how to enhance the safety, compliance and effectiveness of your VRF system. Let’s get started.
VRF System Description
In a VRF system, there generally is one outdoor condensing unit that connects with multiple indoor evaporating units.
In essence, the term “variable refrigerant flow” refers to the ability to modulate the amount of refrigerant going into each of the evaporating units. This refrigerant flow is adjusted through a pulse modulating valve (PMV), which provides individualized comfort control to room occupants.
Mainly, there are two different types of VRF systems: heat pump systems and heat recovery systems.
- Heat pump systems are used in applications that require heating or cooling only but not simultaneously.
- Heat recovery systems are used where you need both simultaneous heating and cooling.
Based on requirements, additional tweaking to these systems is possible. All in all, VRF systems are widely used in hotels, dormitories, hospitals, office buildings, and apartment buildings, which leads us to our next point on VRF system advantages:
VRF System Advantages
Though the VRF system offers numerous advantages, the most important ones are as follows:
Higher energy efficiency —VRF systems use inverter, variable speed compressors, and these systems vary the refrigerant flow rate per the need, so they are known for higher energy efficiency. In fact, according to the Department of Energy (DOE), VRF systems can have “an estimated 30% energy savings over baseline conventional HVAC systems, but this will vary by building application.”
Precise yet easy control of room temperature — Individualized comfort is another benefit of VRF systems. Occupants can adjust the temperature to their liking with controls on indoor units, which is why VRF is such a popular choice in dormitories and hotels, for instance.
Adaptive design — In comparison to conventional HVAC systems, VRF systems are compact. For instance, there is smaller refrigerant piping, which works well for buildings that have tight space requirements. Not to mention, VRF makes for easy installations and is often a good choice for retrofits because of the adaptive design.
Improved reliability and reduced noise levels — If one indoor evaporating unit malfunctions and/or breakdowns, this failure does not affect the entire system, so occupants in other zones relying on other evaporating units can continue on with their day. In this sense, VRF systems are quite reliable.
Additionally, they are also very quiet and operate at low decibels. In fact, occupants won’t hear the typical loud noises associated with HVAC systems because the noisier condensing units are located outside the building.
After discussing these most important advantages of VRF systems, it is fair to mention a caveat with VRF systems: The high-volume design of VRF systems can be difficult sometimes.
Refrigerant Leakage with VRF Systems
Like with other HVAC systems, you need to be concerned about refrigerant leakage with VRF systems, too.
ASHRAE 15 compliance — A VRF system that has a refrigerant leak is a serious concern that can pose a danger to the health and safety of room occupants. Notably, the high-volume design of VRF systems can pose a challenge to facility managers and maintenance personnel. If a refrigerant leak were to occur, all of the refrigerant charge could be directly released into a particular room.
Moreover, the total quantity of refrigerant in the piping must comply with ASHRAE Standard 15, so you need to continuously monitor the refrigerants in use, and that’s where a VRF refrigerant detector, such as Bacharach’s MVR-300, can help.
As you can see, there are some concerns with VRF systems, particularly when it comes to refrigerant leakage. The fact of the matter is, you have a responsibility to protect your occupants from this issue, and that’s why you should consider applying refrigerant leak detection, which leads us to our final point:
Help Ensure Comfort and Safety of Occupants with Refrigerant Detection
Ultimately, you need to prevent refrigerant leaks with VRF systems to help ensure comfort and safety of occupants. Improper installation or maintenance, inadvertent damage or mechanical wear can result in leaks over time.
Bacharach’s MVR-300 refrigerant detector helps keep occupants comfortable in conditioned spaces by providing early warning of refrigerant leaks over the service life of the VRF system.
For instance, the MVR-300 is always awake even as your occupants are sleeping, ready to respond with a configurable “silent” alarm and Modbus communication. Capable of communicating in the background, this leak detector can alert the facility manager or Building Management System (BMS) to identify the specific room and take immediate action.
Even more, the use of the MVR-300 in occupied, conditioned spaces can detect a refrigerant leak well before the Refrigerant Concentration Limit (RCL) with alarm set-points as low as 500 ppm (consistent with ASHRAE provisions for fixed refrigerant detectors) to enhance safety.
Importantly, as VRF systems gain market share in North America, the experts at Bacharach have the instrumentation necessary to provide you a peace of mind. A comprehensive approach to refrigerant leak management is of the utmost importance, and that’s where we can help. Learn more today here. ∎
What do you think about these VRF system pros and cons? How is your team preventing refrigerant leaks with these systems? Let us know by leaving a comment below.