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We offer a 3-year warranty on our products, covering material and workmanship defects. If a defect occurs within the warranty period, please contact us to arrange a return or replacement.

For returns, you have 30 days from receipt of your order. Please contact us to obtain a return authorization and instructions. Ensure that the products are in their original packaging.

If a product is currently out of stock, we do our best to restock it as quickly as possible. You are welcome to let us know if a specific product is missing, and we will check whether we can source it for you in advance.

Yes, we offer custom-made plate heat exchangers tailored to our customers' specific requirements. If you need a bespoke solution, please contact us with your specifications, and we will gladly 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)

Counterflow and Parallel Flow 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 also significantly by the flow directions of the involved fluids. If both fluids flow in the same direction inside the plate heat exchanger, this is called the parallel flow principle. If they flow past each other in opposite directions, it is called the counterflow principle.

The flow direction significantly affects the mean temperature difference between the fluids, which is crucial for the efficiency of heat transfer. Therefore, we explicitly recommend the counterflow principle. Connect the plate heat exchanger according to the diagram provided on the unit. More information is available on our blog.

Finding the right plate heat exchanger doesn’t have to be complicated. If you have any questions or need assistance, don’t hesitate to contact us. We’ll gladly help you choose the right model for your requirements.

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