Armstrong is pleased to announce the release of a new technical whitepaper:
The Advantages of Hydronic Systems versus Variable Refrigerant Flow (VRF) – A Critical Analysis
This new whitepaper presents a review of technical literature plus post-installation analysis of three types of HVAC systems: Variable Refrigerant Flow (VRF), Hydronics and Hydronics integrated with Armstrong Design Envelope technology. The paper points out the differences between the system types and reveals that cost-savings claims made by VRF manufacturers are not supported by the data. Hydronic systems are less expensive than VRF systems, and Hydronic systems that use Design Envelope technology are far less expensive.
Key findings include:
To mitigate the potentially lethal effects of refrigerant-induced asphyxiation, VRF requires extensive design considerations (zoning changes, refrigerant leak detection, etc.) that increase installed cost
Traditional hydronic systems range between $11.9/ft2 and $31/ft2 for schools and apartment buildings, respectively. VRF systems cost between $14.90/ft2 and $34/ft2 for the same installations – 9.7% and 25.2% higher than hydronic systems.
The rated heating Coefficient of Performance (COP), which is a direct measure of energy efficiency for VRF system, is based on an outdoor air temperature of 47°F. Below this temperature, the COP for VRF systems degrades considerably - up to 30%.
In addition, the rated COP for a VRF system is based on a system piping length of 25ft. The actual installed COP of VRF systems decreases with every additional foot of piping above 25ft.
On an annualized basis, hydronic systems offer energy savings of 57% to 84% compared to a VRF systems installed in the same building, addressing similar loads
Click here to access the White Paper