Gas-to-gas plate heat exchangers

When is a gas-to-gas plate heat exchanger the right choice?

Gas-to-gas plate heat exchangers transfer heat between two air or gas streams without the streams mixing: fresh air and extract air pass through the heat exchanger on separate levels. That makes the design the first choice for heat recovery in ventilation systems and for processes where extract air must not reach the supply air - with loaded or odorous exhaust air, for instance. There are no moving parts; unlike a rotary heat exchanger, the transfer stays low in leakage. Where the air paths must be sealed from each other, the fully welded version is available (see below).

Which designs are available?

The configurator holds the cross-flow plate heat exchanger for pure heat recovery. The enthalpy plate heat exchanger, which additionally transfers moisture through a vapour-permeable membrane - relevant where the supply air should not become too dry in winter - we size on request. The catalogue covers 11 edge lengths from 300 to 2400 mm and volume flows from a few hundred up to 100,000 m³/h; for large air volumes the sizing combines several modules.

Which materials can be chosen?

Four plate materials are available: aluminium for the standard case, coated aluminium for corrosive condensate (from humid process exhaust air, for instance), stainless steel for high temperatures and aggressive media, and plastic for particularly corrosive applications. You make the preselection in the configurator; the final material recommendation is part of the quote.

How is the plate heat exchanger installed?

The standard version is the built-in block: the plate pack sits inside the ventilation or process unit, whose casing separates the two air paths. For direct connection to ductwork there is a version with a surrounding frame for flanging, optionally with dampers - as a bypass for frost protection or free cooling in summer, for instance. For temperatures above 600 °C, or where the air paths must be sealed from each other, there is a fully welded stainless steel version. The online sizing calculates the built-in block without bypass; frame, dampers and the welded version are specified in the quotation.

What determines plate spacing and pressure rating?

Depending on the material, the clear gap between the plates ranges from 2 to 14 mm. Narrow gaps fit a lot of transfer surface into a small space; wider gaps lower the pressure drop and foul more slowly - the better choice for exhaust air laden with dust, grease or paint mist. The sizing picks the gap to match your permissible pressure drop. How much pressure difference the two air sides may have depends on the plate material: metal blocks withstand considerably more than plastic or enthalpy blocks, and some series lose strength with hot exhaust air - we take this into account when sizing your quotation. The plate pack itself has no moving parts; its maintenance comes down to visual inspection and cleaning of the plate pack.

How does the online sizing work?

You enter volume flows, temperatures and humidities for both sides together with your permissible pressure drop; the page calculates dew point, enthalpy and mass flow visibly as you type. The sizing itself runs on our server against the design catalogue; our team reviews it and comes back to you with the result by e-mail. You then receive an individual quote with a binding design - only there do the type and dimensions appear.