DHW tank with double-wall heat exchanger

Refrigeration heat,
turned into hot water.

KondTherm DXR recovers the heat your refrigeration plant or heat pump already rejects and turns it into hot water of up to 65 °C — directly inside the tank, fully isolated from the sanitary water, at 10–210 kW.

Capacity1,000–5,000 L Output10–210 kW SafetyEN 1717 Lining316L / bio-ceramic
KondTherm DXR insulated domestic hot water tank
Double-wall coilrefrigerant never meets the water
The principle

Stop throwing away your condenser heat.

Every heat pump and every refrigeration plant rejects heat at its condenser — heat normally dumped to the air. KondTherm DXR puts that heat to work.

The refrigerant condenses directly inside the tank, against the sanitary water — no intermediate water loop, so the system runs at a higher COP.

◂ refrigerant in (hot gas)water up to 65 °C ▸

The deeper and more continuous the refrigeration, the more — and the hotter — the recovered heat. Low-temperature freezing rejects the most, at the highest gas temperature.

−40 °C deep freeze→ hottest recovery
Direct
refrigerant condensation (DX) — no water loop
10–210
kW, built from 10 kW modules
↑ COP
higher efficiency than water-to-water
Safety · EN 1717

A wall between the refrigerant and your water.

Every refrigerant path through the tank is a tube within a tube. The refrigerant flows in the inner copper tube; an outer wall surrounds it with a controlled gap.

If either wall is ever breached, the refrigerant escapes into that gap — visible at the connection — and can never reach the sanitary water. That is the principle behind EN 1717 potable-water protection.

CROSS-SECTIONrefrigerant flow ▸
REFRIGERANT ▸▸▸
potable waterleak-detection gaprefrigerant (inner tube)
Double-wall refrigerant connections
The lower fitting reveals the inner tube inside the outer wall.
Production

Made to European standards.

Stainless steel tank body in production
Welded tank connections
Tank connection assembly
Finned coils inside the inspection flange
The essentials

Four points that matter.

01

Direct condensation (DX)

The refrigerant condenses directly inside the tank — no intermediate water loop, so the whole system runs at a higher COP.

02

Double-wall heat exchanger

Refrigerant and drinking water stay fully separated; any leak is led to a detectable gap and never into the water.

EN 1717
03

Modular 10–210 kW

Built from 10 kW double-wall exchanger modules — add modules to match the load, as one merged exchanger or several independent circuits.

04

Two internal linings

Choose AISI 316L stainless steel or carbon steel with a flexible polymer bio-ceramic coating — both suitable for potable water.

Construction

Pick the lining your water demands.

/316 · AISI 316L

Stainless steel

Premium grade for the most demanding water and the strictest hygiene.

  • Potable, sanitary & food-contact duty
  • Chlorinated or corrosive water
  • Marine applications
  • Bare interior — no coating required
/C · S235JR + lining

Polymer bio-ceramic

Carbon steel protected by an internal polymer bio-ceramic coating containing biocides.

  • Flexible, high adhesion — resists micro-cracking
  • Biocide content inhibits pitting corrosion
  • Sacrificial magnesium anode, or optional impressed-current anode
  • Certified to EN 12897
Technical data

Six sizes, up to 210 kW.

ModelVolume (L)Ø w/o insul. (mm)Ø w/ insul. (mm)Height (mm)Max exchangers ×10 kWMax power (kW)
1000100885010502260660
15001449100012002360990
2000215812001400245012120
3000305014001600256015150
4000405116001800263021210
5000505516001800313021210

Rated 6 bar / 95 °C · output configured by the number of 10 kW double-wall modules · custom builds available — dimensions and connection configurations to customer requirements.

Water temperature

From heat recovery the store reaches up to 65 °C, and the upper zone up to 70 °C where the hot discharge gas is desuperheated. The vessel itself is rated to 95 °C, and a connection for an electric element is provided for Legionella protection or a top-up.

Body & protection

Carbon steel S235JR (bio-ceramic lining + magnesium anodes) or AISI 316L (1.4404) stainless, with a 3–4 mm wall depending on model. Flanged inspection hatch for service, 5-year warranty.

Insulation

Four removable options: PL/PVC, PU/PVC, PL/ABS and the premium PS/ABS (100 mm graphite polystyrene, ErP-compliant — class B up to 500 L, class C to 2000 L).

Standards & references

Built to the European framework.

EN 1717

Potable-water protection

The double wall keeps refrigerant and drinking water apart.

EN 12897

Storage water heaters

The tank lining is certified to this standard.

PED 2014/68/EU

Pressure equipment

Applies to the refrigerant-side heat exchanger.

ErP · 814/2013

Ecodesign

Standing-loss limits for tanks up to 2000 L.

Where it fits best

Deep, continuous cooling meets large hot-water demand.

A few examples, not the full list. As a rule it suits any site where refrigeration runs around the clock and hot water is in constant demand.

Meat, poultry & abattoirs
82 °C sanitation + chilling
Dairy, cheese & ice-cream
CIP + deep freezing
Cruise ships & marine
chillers + potable DHW
Water parks & spas
dehumidification heat
Ice rinks & arenas
24/7 ice plant
Commissary kitchens
cold rooms + pot-wash

Specifying it for a project?

Send us the project and we will help you size it, or ask for the datasheet and a quotation.