Solution · Water Supply

Dehumidification in
Waterworks

Cold water cools pipes, tanks, and fittings below the dew point of the ambient air – condensation forms. DÖLCO uses humidity-controlled condensation dehumidification to keep the dew point safely below the component surface, protecting your systems from corrosion.

Dehumidification calculator for your waterworks →Expert advice: +49 7664 50559-0

The Problem

What condensation causes in waterworks

The surface temperature of system components is close to the water temperature – and thus below the dew point of the ambient air. The result: permanent condensation on cold surfaces with expensive consequential damage.

Corrosion & Rust
Condensation on pipes, pumps, tanks, and fittings leads to corrosion and shortens the service life of the systems.
Peeling protective coatings
Permanent moisture infiltrates coatings and paints – the bare metal surface continues to rust.
Failure of switchgear
Condensate on control cabinets, sensors, and actuators causes malfunctions and costly downtime.
Hygiene & Building structure
Dripping water, mold, and mildew jeopardize hygiene and the building structure in the sensitive drinking water environment.

The Solution

Humidity-controlled dehumidification according to DÖLCO standard

DÖLCO systems operate on the recirculation principle and lower the water vapor content of the ambient air so that the dew point always remains below the coldest component surface – preventing any further condensation.

Reliable corrosion protection
No more condensation on pipes, pumps, and switchgear – the systems remain dry and durable.
Hygiene secured
Consistently low humidity prevents mold and protects the drinking water environment.
Energy-efficient with ITR
The DÖLCO ITR dew point control dehumidifies exactly as needed and reduces operating costs by up to two-thirds.
Remote monitoring with KISS
Optionally with DÖLCO KISS-IoT: Keep an eye on humidity and operation remotely at any time.

Expertise

How the dehumidification capacity is calculated

The design follows the DVGW regulations and the h,x diagram according to Mollier. Two steps lead to the required unit capacity:

1. Dehumidification load Δx
The actual water vapor content x_R results from room temperature and humidity. The target dew point is 2 °C below the surface temperature, providing x_target. The dehumidification load is Δx = x_R − x_target (in g H₂O per kg of air).
2. Design formula
L = V · ρ · Lw · Δx / 1000 [kg H₂O/h] – with room volume V, air density ρ ≈ 1.2 kg/m³, and air exchange rate Lw ≈ 0.4/h (DVGW, well-sealed rooms).
Rule of thumb: approx. 2 kg H₂O/h per 1,000 m³ of room volume for standard systems.

Calculator

Dehumidification calculator for your waterworks

Enter the room data – the calculator determines the required dehumidification capacity and recommends the appropriate DÖLCO system. Non-binding preliminary design.

Result
Dew point of ambient air12,5 °C
Dehumidification load Δx2,4 g/kg
Required dehumidification capacity2,30 kg H₂O/h
corresponds to55 l/24 h
Recommended DÖLCO system
DÖLCO K 8000
96 l/24 h · stationary · console, no tank · incl. planning reserve (88 l/24 h)
Alternatives
3 × DÖLCO K 3000Console · no tank132 l/24 h
2 × DÖLCO LE-25000 minimobile · movable158 l/24 h
3 × DÖLCO LE-3600mobile · movable99 l/24 h
Several smaller units distribute the dehumidification more evenly in angled areas. Mobile units (with tank) can also be moved flexibly – console units are permanently installed without a tank.
Attention: With these values, the ambient air is already condensing on the surface – dehumidification is urgently needed.
View suitable systems →

Note: The nominal capacity of the units applies under test conditions (32 °C / 90 % RH). In a cooler waterworks, a condensation dryer delivers less – this preliminary design includes a reserve. The final detailed design is based on the unit's performance curve and our expert consultation.

Products

The right DÖLCO systems

For stationary continuous dehumidification in waterworks – console units and large industrial systems, all with hot gas defrosting and ITR connection.

K-Series (Console units)
44 to 240 l/24 h – for pumping stations, elevated tanks, and technical rooms up to ~2,300 m³.
T-Series (Large industrial systems)
360 to 2,000 l/24 h – for large halls and facilities up to 16,000 m³.
Dew point control ITR
Measures at the coldest point and dehumidifies exactly as needed – up to two-thirds less operating costs.
View all stationary systems →

Made in Freiburg – for over 60 years

DÖLCO has been developing and manufacturing dehumidification technology in Germany for decades and reliably protects waterworks, energy suppliers, and industry from moisture damage – with standard-compliant design according to DVGW.

FAQ

Frequently Asked Questions

Why is ventilation in the waterworks not sufficient?
With warm, humid outside air in summer, condensation actually increases – the warm air cools down on the cold pipes and releases even more water. Only controlled dehumidification keeps the dew point reliably below the surface.
Condensation or adsorption dryer?
In waterworks, the condensation principle (DÖLCO K-/T-Series) is the most economical. Thanks to hot gas defrosting, the units also work at low room temperatures. Adsorption is only used in case of frost or very low target humidity levels.
How accurate is the calculator?
It calculates exactly according to the DVGW/Mollier method and is verified against original DÖLCO design examples. It provides a reliable preliminary design; we coordinate the final dimensioning individually.
How does the ITR control reduce costs?
The dew point control measures directly at the coldest component and only switches on the dehumidification when there is a real risk of condensation – this saves up to two-thirds of operating costs compared to a fixed humidity setpoint.
Can the systems be monitored remotely?
Yes. With the DÖLCO KISS-IoT system, humidity, operation, and faults can be monitored and documented regardless of location.

Consultation

Need your waterworks designed?

Our expert consultants will dimension your dehumidification individually and create a suitable offer – free of charge and without obligation.

📞 +49 7664 / 50559-0✉ info@doelco.de