The programme scope covers Gasketed plate heat exchangers, Brazed plate heat exchangers and Fusion-bonded plate heat exchangers designed for liquid/liquid heat exchange (without phase change) applications in the Heating Ventilation and Air Conditioning (HVAC) field and operated with clean water or clean water mixtures (ethylene/propylene glycol but also ethanol aqueous solutions).
The detailed scope is specified in OM-25.
The full list of useful definitions can be consulted in RS 7/C/010. Some are presented hereafter.
Brazed plate heat exchanger
A brazed plate heat exchanger consists of a pack of thin corrugated metal plates. A thin foil of brazing material (generally copper) brazes two adjacent plates together as it melts in a high temperature furnace. The melted foil also seals the channel formed between two plates. In order to retain high internal pressure, two thicker front and end plates are normally brazed to both sides of the plate pack. Connections for media are either brazed or welded to the front plate.
Product of the heat exchange fluid mass flow rate and the difference between the specific enthalpies at the inlet and outlet connections.
Fusion-bonded plate heat exchanger
A fusion-bonded plate heat exchanger consists of a pack of thin corrugated metal plates. The sealing principle is the same as for brazed plate heat exchanger except that the brazing material is replaced by a filler material that “bonds” two adjacent plates together instead of “brazing” them.
Gasketed plate heat exchanger
A “plate and frame” or “gasketed” heat exchanger consists of a pack of corrugated metal plates held together in a frame. Each plate is fitted with a gasket, which seals the channel formed between two adjacent plates and directs the fluid into alternate channels. The plate pack is assembled between a fixed frame plate (headpiece) and a movable pressure plate (tailpiece) and compressed by tightening bolts. The pressure plate is suspended from an upper carrying bar and guided by a lower guiding bar, both of which are fixed to a support column.
A plate heat exchanger is considered to be operating in Heating, Ventilation and Air-conditioning (HVAC) applications when it directly or indirectly serve either of the heating, cooling or tap water system in any kind of building.
The definition from EN 305:1997 applies: “loss in total pressure between the inlet and the outlet including channels for flow distribution to and from the heat transfer surface”.
In the present LPHE certification scheme, a range is defined as a family of plate heat exchangers models of the same product type (gasketed or brazed or fusion-bonded) named under a unique designation. This designation shall be proper to models that fall into the LPHE certification programme scope to avoid any risk of confusion.
When tested in the laboratory the obtained performance data shall not differ from the declared values by more than the following acceptance criteria:
Pressure drop on primary fluid circuit +(10%+Mu) with +2kPa as a minimum
Pressure drop on secondary fluid circuit +(10%+Mu) with +2kPa as a minimum
With Mu the expanded uncertainty calculated by the laboratory for the test in question (uncertainty analysis as per RS 7/C/010).