Separates the circuits
Limescale and oxygen from the mains water can't enter the boiler circuit. The boiler, exchanger and pipework are protected from corrosion; the boiler water treatment stays intact.
Product group 01
Plate Heat Exchangers
Equipment that separates the boiler circuit from the domestic water circuit, delivering high heat transfer in a small footprint. It directly affects both the efficiency and the lifespan of the boiler room.
Capacity20 kW – 5 MW
Design pressurePN10 / PN16 / PN25
Operating temperature−10 °C … +180 °C
Plate materialAISI 316 / Titanium
Counter-flow operation · hot circuit on the left, cold circuit on the right
Why it's needed
What does a heat exchanger do in the boiler room?
You don't send boiler water straight to the tap. A heat exchanger physically separates the two circuits: it passes heat through, but not water. It's the quietest yet most critical piece of equipment in the boiler room.
Produces hygienic hot water
Since water is heated instantaneously, it isn't held in large volumes for long periods. The legionella risk associated with storage drops significantly when properly designed together with a buffer tank.
Saves space in the boiler room
The plate type occupies a much smaller footprint than a shell-and-tube unit of the same capacity. This becomes decisive in tight boiler rooms and retrofit projects.
Separates pressure zones
In high-rise buildings, the static pressure at lower levels strains the boiler. By zoning with a heat exchanger, each circuit runs at its own pressure.
Efficiency through a small approach temperature
Counter-flow plate geometry can reach a 2–5 °C approach temperature. This is what pays off in waste-heat recovery and low-temperature regimes.
Can be opened for cleaning, and expanded
In the gasketed type, plates can be opened up and cleaned. When capacity needs grow, plates can be added without replacing the frame — a real advantage in projects that expand over time.
Types
Which type, for which job?
All three types transfer heat; what sets them apart is maintainability, pressure rating and how dirty the fluid is.
Gasketed plate
The standard solution for boiler rooms, domestic hot water and district heating lines.
- Can be opened for cleaning
- Expandable by adding plates
- Watch the gasket temperature limit
Brazed plate
No gaskets; brazed with copper or stainless steel. For cooling circuits and compact applications.
- High pressure rating
- Small footprint, low cost
- Cannot be opened, cleaned chemically
Shell-and-tube
For dirty or particle-laden fluids, steam applications and high temperatures.
- Tolerant of fouling
- Can operate with steam
- Larger footprint
Selection criteria
What data determines the right heat exchanger?
Once the eight items below are clear, the selection narrows to a single model. We calculate anything you don't have.
ParameterWhy it mattersWhat we need from you
Thermal capacity
The amount of energy to be transferred. Over-sizing raises upfront cost; under-sizing causes loss of comfort.
kW or kcal/h
Temperature regime
Inlet–outlet temperatures of the primary and secondary circuits. Directly determines the approach temperature and plate count.
e.g. 90/70 – 10/60 °C
Flow rate
The fluid volume passing through each circuit. Determines the number of plate channels and connection diameter.
m³/h or l/s
Allowable pressure drop
Affects pump selection. Kept low, the exchanger grows larger; kept high, pump energy use increases.
kPa (typically 20–50)
Operating and design pressure
PN class based on building height and static pressure. Can be decisive on its own in high-rise buildings.
PN10 / PN16 / PN25
Fluid type and fouling
Water, glycol mix, steam, seawater or process fluid. A fouling factor is added as a margin to capacity.
Fluid + fouling margin
Plate and gasket material
Determines corrosion resistance. In water with high chloride content, stainless isn't enough — titanium is required.
AISI 316 / Ti · EPDM / NBR
Connection type and size
Compatibility with the existing installation. Flanged, threaded or welded, along with mounting clearance and service space.
DN size + connection type
This much is enough for a quote
You don't need all of it. We'll work out anything missing together with you.
Create a quote request- Capacity, or building/facility size
- Boiler flow and return temperatures
- Domestic hot water temperature and flow rate
- Number of building floors or static pressure
- Fluid type (water, glycol, steam)
- Mechanical project or specification, if available
FAQ
Questions from the field
The four questions we hear most often at the quote stage.
Should the exchanger capacity match the boiler capacity?
No. While the boiler feeds the whole building, the exchanger only serves its own circuit. The domestic hot water exchanger is sized together with instantaneous water consumption and buffer tank volume; matching it to boiler capacity produces an unnecessarily large and expensive selection.
How often should the plates be cleaned?
It depends on water hardness and operating temperature. In a properly treated circuit, problems may not appear for years; with hard mains water, an annual check is reasonable. The sign is clear: a drop in outlet temperature at the same regime, together with rising pressure loss, indicates scaling.
Should I choose gasketed or brazed?
Choose gasketed if it will need to be opened for cleaning or expanded later. If space is tight, pressure is high, and the circuit is closed and clean, brazed is more economical. For domestic hot water applications in boiler rooms, the gasketed type is generally preferred.
What else is needed alongside the exchanger?
Usually a circulation pump, strainer, safety valve, expansion tank and a valve group for circuit separation. Bundling these into a single quote is an advantage for both compatibility and lead time — we can supply all of them.
Next step
Let's work out the capacity together
Write in with what you have; we'll ask for anything missing. Your quote will be ready within the business day.