Comparison between Spiral Flat Heating Coils and Conventional heating coils in Hot Water Tanks

The high-capacity EHSF hot water tank by Ecotherm features a spiral flat heating coil installed at the bottom of the tank, an exclusive and patented innovation unique to Ecotherm. This design enables faster heat transfer, increases usable hot water volume by up to 30% compared to traditional tanks, and optimizes both space and energy efficiency.

To better understand how this patented spiral flat heating coil technology from Ecotherm Austria differs from traditional hot water tanks, let PGTECH walk you through some of its unique features and outstanding advantages in this article.

Introduction to Ecotherm (Austria) High-Efficiency Flat Coil Hot Water Tanks – The Most Innovative Solution

Comparison Between Conventional Heating Coils and ECOTHERM Spiral Flat Heating Coils

With its unique design, the spiral flat heating coil positioned at the lowest and coldest part of the storage tank ensures highly efficient heat transfer and a lower return temperature. The EHSF industrial hot water tank is ideal for efficiently meeting peak hot water demand in various applications such as stadiums, hotels, residential buildings, schools, and heat recovery systems.

Detailed comparison between conventional hot water tanks and Ecotherm (Austria) industrial hot water tanks:

1. Conventional Heating Coils

Conventional heat exchangers typically operate within a mixed temperature range of 10°C to 60°C, which reduces heat transfer efficiency. During the heating process, the coil creates internal circulation within the tank, requiring higher energy consumption. As a result, the usable hot water volume is often limited to around 70% of the total tank capacity.

• Up to 30% reduction in effective volume and increased risk of Legionella bacteria growth
• Reduced heat stratification efficiency across coil layers, from the first to the last
• Limited heat exchange surface area and reduced installation flexibility
• Increased primary energy consumption

2. ECOTHERM Spiral Flat Heating Coils (High Efficiency)

The patented spiral flat heating coil is installed horizontally at the bottom of the storage tank. It operates 100% within the cold water zone, corresponding to a single temperature range. Its installation directly above the tank base, combined with a low profile height (only 13 cm), enables nearly complete heating of the entire tank volume.

The specially engineered tank design ensures:

• High usable hot water volume (up to 97% of total tank capacity)
• Hygienic water quality
• High efficiency due to optimized heat transfer
• Optimized thermal stratification
• Effective energy savings

Comparison Between Conventional Hot Water Tank Technology and ECOTHERM EHSF High-Efficiency Tank (Austria)

Ecotherm conducted a detailed analysis comparing the ECOTHERM “EHSF” high-capacity commercial hot water tank with conventional hot water tanks. Using CFD (Computational Fluid Dynamics) simulations, Ecotherm evaluated fluid flow and thermal stratification in two tanks with the same capacity and heat exchange surface, based on four comparison scenarios.

Comparison 1: Heating to 60°C in 30 Minutes

After 30 minutes, only the ECOTHERM “EHSF” tank is heated 100% to approximately 61°C.

Comparison 2: Hot Water Draw-Off at 12 L/min for 10 Minutes

After 10 minutes of hot water usage, the thermal stratification in the ECOTHERM “EHSF” tank remains intact.

Comparison 3: Hot Water Draw-Off at 20 L/min for 10 Minutes

Thanks to its superior heat transfer capability, the ECOTHERM “EHSF” heat exchanger maintains higher stored thermal energy compared to conventional tanks.

Comparison 4: Hot Water Draw-Off at 50 L/min for 10 Minutes

With conventional tanks, only about 50% of the stored volume remains at 45°C. In contrast, the ECOTHERM “EHSF” industrial hot water tank maintains approximately 80% of its volume at 45°C.