During on-site commissioning, a common situation is often encountered: the outlet temperature of the hot and cold heat exchanger consistently fails to reach the set value, the steam valve has been opened to a relatively large opening, and the return water temperature remains low. After disassembling and inspecting the heat exchange core, it is often found that the heat exchange area was estimated empirically during the selection stage and is actually too small; conversely, selecting an excessively large area increases equipment investment and occupies more installation space. For design and selection personnel, the root cause of the problem usually lies not in the operation stage, but in the completeness of data and the matching method at the early stage of selection.
An undersized and an oversized heat exchange area are a pair of mutually constraining errors. When calculating by empirical values, if any one of the three conditions—medium temperature, heating/cooling rate, and installation space—deviates from the actual working conditions, the calculation result will be distorted. Inlet and outlet temperature and pressure data differ significantly across seasons. Selecting based on a single operating point alone can easily lead to insufficient capacity or wasted margin when the load changes.
For the HRS-920 hot and cold heat exchanger, it is recommended to record inlet and outlet temperature and pressure data for different seasons before selection to form operating condition parameter records, and then perform matching calculations in combination with medium temperature, heating/cooling rate, and installation space. This model is suitable for heat exchange occasions between hot and cold media. During design, the heat exchange area configuration can be adjusted based on the recorded data so that the heat exchange capacity adapts to load changes while balancing investment and footprint.
Operating data after commissioning is also of reference value. By comparing actual inlet and outlet temperatures and pressures with design values, it is possible to determine whether the heat exchange area has a reasonable margin and to provide a basis for selection adjustments in subsequent projects of the same type. For design and selection personnel, this closed loop makes it easier to control deviation than relying solely on empirical estimation, and also makes it easier to quickly determine the adjustment direction during capacity expansion or retrofit.
