Dr. Halil İbrahim Dağ

R290 Heat Pumps: Safe Innovation, Not a Hidden Hazard

14 Jul 2026Heat Pumps

Dr. Halil İbrahim DağBoard Member / Technical Coordinator

R290 heat pumps run on propane, a natural refrigerant with near-zero global warming potential and excellent efficiency. The trade-off is A3 flammability — managed through charge limits, leak detection, sealed components and certified installation. With EU F-Gas rules squeezing out high-GWP refrigerants, R290 is a safe, forward-compatible choice when installed and maintained professionally.

Read more: R290 Heat Pumps: Safe Innovation, Not a Hidden Hazard

Effect of Elliptical Coil Geometry on Heat Transfer

12 May 2026Storage Tanks

Dr. Halil İbrahim DağBoard Member / Technical Coordinator

Elliptical coil geometry measurably outperforms the traditional circular tube in heat exchangers: more heat-transfer surface in the same volume, turbulence that disrupts boundary layers, higher Nusselt numbers at the same Reynolds numbers — and, in many configurations, a lower pressure drop, so less pumping energy. For coil-in-tank heat exchangers and compact solar thermal systems, that combination makes elliptical designs a serious engineering option.

Read more: Effect of Elliptical Coil Geometry on Heat Transfer

Advantages of EVI Compressors in Heat Pump Systems

18 Nov 2025Heat Pumps

Dr. Halil İbrahim DağBoard Member / Technical Coordinator

Enhanced Vapor Injection (EVI) compressors inject extra refrigerant vapor mid-compression through an economizer circuit, keeping heat pumps efficient in deep subzero conditions. The result: up to 30% more heating capacity, higher COP, stable operation down to -20°C (some models -30°C) and lower operating costs — making EVI a key technology for cold-climate heat pump deployment, supported by EU and national incentive programs.

Read more: Advantages of EVI Compressors in Heat Pump Systems