This page collects the answers to the most frequently asked questions about plate heat exchangers and the products we produce, with the objectiveof offering a simple and useful consultation tool for all users interested in them.

Gasketed plate heat exchangers

Connection to the system of the PHE

Question: is it possible to change the connection to the system with respect to the indications given on the arrangement of the connections?

Answer: yes. The exchangers are symmetrical inside, and therefore the primary and secondary circuits can be exchanged. It is also possible to invert the inputs with the outputs, but be careful to invert them on both circuits of the exchanger in order to respect the countercurrent flow.

Exchanger increasing

Question: is it possible to increase the performance of the exchanger?

Answer: for gasketed exchangers yes. The alignment bars and the boltings are sized to ensure an expansion of at least 20% of the plate pack, and consequently of performance.

Plate cleaning

Question: do I have to clean the plates periodically?

Answer: yes. It is good practice to perform a scheduled cleaning maintenance. The frequency of this operation depends on the type of operating fluids, their degree of fouling, the operating temperatures and other specific factors related to the plant and the type of thermal operation that the exchanger performs.

Gasket type of the PHE

Question: are the gaskets of the heat exchangers glued?

Answer: no. All Termoleader gaskets are non-glued type.

Insulation of the PHE

Question: is it necessary to insulate the exchanger?

Answer: it is not necessary but recommended. Each model in our range has its own IsoLeader insulation box which, thanks to the LeaderLock system, can be assembled and disassembled after installation of the exchanger in a few moments.

threading type

Question: is the threading of the connections male or female?

Answer: the standard thread of the Termoleader connections is male.

Swimming pool water heating with BPHEs

Question: brazed heat exchangers are suitable for pool heating?

Answer: no. Copper brazing is not compatible with the chloride content in the pool water and would be rapidly corroded causing the brazed exchanger to break.

Gasket replacement

Question: how often do I replace the gaskets?

Answer: the gaskets have elastic characteristics that guarantee the tightness of the plate pack. Over time, the gasket decays and the elasticity decreases until it is no longer able to guarantee the seal of the exchanger. It is possible to tighten the plate pack further up to a minimum limit, beyond which it is necessary to replace the gaskets. Unfortunately, it is difficult to establish the times within which the complete deterioration of the gaskets takes place, this being a function of many parameters, from fluids to operating temperatures, from variations in temperature to pressure values. Once you know the nature of the system and the behavior of the gaskets in operation, you can determine the ideal time for maintenance and replacement of the gaskets.



Question: does the unit adjust the domestic hot water automatically?

Answer: yes. The domestic hot water setpoint can be set as desired and the Leaderbox-AIW regulates the domestic hot water temperature by modulating the flow rate of the primary circuit.


Question: Can the unit be connected to a recirculated system?

Answer: yes. It is necessary to provide the additional recirculation kit, including the additional connection for the return of the recirculation and the relative thermometric probe. It is also possible to set the recirculation setpoint in a completely independent way from that of the instantaneous production of domestic hot water.

Primary temperature limitation

Question: is it necessary to limit the delivery temperature of the primary with a mixing valve?

Answer: no. The regulation system adapts to every situation of primary temperature in a precise and dynamic way.

Puffer connection

Question: is it necessary to connect the Leaderbox-AIW to a primary puffer?

Answer: it is preferable. The primary circuit is regulated by modulating the circulation pump speed, for this reason it is important that the flow rate of the primary circuit of the unit is not disturbed by other pumping systems present on the system.


Circuits A and B

Question: is it possible to invert circuits A and B?

Answer: yes. The circuits are symmetrical both in terms of heat exchange and circulation.

Electrical connections

Question: how should I make the electrical connections?

Answer: it is sufficient to connect the contacts present in the terminal board of the unit, to which the components contained in the Leaderbox are already wired.


Question: is the provision of the covering mantle also foreseen?

Answer: yes, the covering mantle is also included in the supply.


Cascade system

Question: is it necessary to provide a cascade system of preparators?

Answer: no. The Termoleader producers are sized according to the maximum requirements of the users and are equipped with a regulation system with LeaderTwin technology that allows an optimal regulation both to the maximum and minimum system regimes. In addition, the flow switch system used is able to detect a minimum flow rate of 1.8 liters per minute regardless of the diameter of the pipe.


Question: is it necessary to insulate the producers?

Answer: the standard producers are equipped with a closing box that is already internally lined with insulating material.

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