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Our products come with a 3-year warranty that covers defects in materials and workmanship. If any defects occur within the warranty period, please contact us to discuss the process for a return or exchange.

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Yes, we offer customized plate heat exchangers designed to meet our customers' specific requirements. If you require customized solutions, please contact us with your requirements and we will be happy to help you find the right heat exchanger for your application.

The mean temperature difference of a plate heat exchanger can be calculated by several methods, depending on the type of heat exchanger and the specific conditions. A common method is the Logarithmic Mean Temperature Difference. Here is how you can calculate it:

Formula for the logarithmic mean temperature difference

LMTD = (ΔT1 - ΔT2) / ln(ΔT1 / ΔT2)

variables

• LMTD: logarithmic mean temperature difference
• ΔT1: Temperature difference at one end of the heat exchanger
• ΔT2: Temperature difference at the other end of the heat exchanger

Example

• Temperature of the hot liquid at the inlet (Th): 150 °C
• Temperature of the cold liquid at the inlet (Tc): 30 °C
• Temperature of the hot liquid at the outlet (Th'): 80 °C
• Temperature of the cold liquid at the outlet (Tc'): 60 °C

1. Calculation of ΔT1 & ΔT2

ΔT1 = Th - Tc = 150 °C - 30 °C = 120 °C

ΔT2 = Th' - Tc' = 80 °C - 60 °C = 20 °C

2. Calculation of the mean temperature difference

LMTD = (120°C - 20°C) / ln(120°C / 20°C)
LMTD ≈ 55.8 °C

Q = U * A * LMTD

• Q: heat flow (W)
• U: total heat transfer coefficient (W/m²·K)
• A: Heat transfer area (m²)
• LMTD: logarithmic mean temperature difference (K)

or

Q = ṁ * cp * LMTD

• Q: heat flow (W)
• ṁ: mass flow rate (kg/s)
• cp: specific heat capacity (J/kg·K)
• LMTD: logarithmic mean temperature difference (K)

Direct current and countercurrent principle

The transferable heat energy of a plate heat exchanger is determined not only by the size of the exchange surface and the heat transfer coefficient (k), but is also significantly influenced by the flow directions of the media involved. When both media flow in the plate heat exchanger in the same direction, this is referred to as the cocurrent principle. However, if they flow past each other in opposite directions, this is the countercurrent principle.

The flow direction significantly influences the average temperature difference between the media, which is crucial for heat transfer efficiency. Therefore, we strongly recommend the counterflow principle. Connect the plate heat exchanger according to the diagram attached to the heat exchanger.

You can find more information in our blog.

Finding the right plate heat exchanger doesn't have to be complicated. If you have any questions or need support, don't hesitate to contact us. We'll be happy to help you choose the right model for your needs.

Our copper-brazed plate heat exchangers are generally suitable for drinking water. However, please note: Particularly soft water (with very low mineral content) or aggressive water (e.g., with very low pH or high oxygen content) can permanently attack the copper brazing.