In industrial heating projects of rooms, chambers or technical enclosures, one of the most frequent problems is that the installation does not reach the target temperature in the expected time.
The usual reaction is usually immediate: “Power is lacking“.
However, in most cases the problem is not only the installed power, but an incomplete or incorrect thermal dimensioning.
Industrial thermal design is not just about calculating kW. It is about understanding how heat behaves inside the enclosure.
What is industrial thermal sizing?
Industrial thermal sizing is the process of calculation and design necessary to determine the power required in power systems:
- Heating of industrial rooms.
- Disinfection or drying chambers.
- Thermal processes with steam.
- Heat treatment enclosures.
This calculation should consider:
- Actual volume of the enclosure.
- Thermal mass of the product.
- Structural thermal losses.
- Target warm-up time.
- Heat distribution and air circulation.
When any of these factors is estimated incorrectly, the system may be clearly undersized.
Common mistake 1 – Underestimating the actual enclosure volume
One of the most common errors in the calculation of industrial thermal power is to work with a theoretical volume that does not coincide with the constructed volume.
A 40-50% increase in volume implies:
- Greater mass of air to be heated.
- More heat exchange surface.
- Increased transmission losses.
- Higher thermal inertia.
The result is that the initially calculated power is no longer sufficient.
Common mistake 2 – Failure to consider the actual thermal mass of the process
The basic energy calculation is based on the formula:
Q=m⋅c⋅ΔT
Where:
- m = real mass.
- c = specific heat.
- ΔT = temperature increase.
The usual problem is not in the formula, but in the actual mass considered.
It is not the same thing:
- Ventilated vs. compact product.
- Dry material vs. material with moisture.
- Hundreds of kilos vs. actual tons per cycle.
If the thermal mass is higher than estimated, the power required can be multiplied by two or three.
Common Mistake 3 – Ignoring thermal stratification in industrial rooms
Thermal stratification in industrial enclosures is one of the most overlooked phenomena in thermal design.
The hot air rises and the cold air remains at the bottom. If there is no correct recirculation or redirection of the air flow, thermal layers are generated.
Consequences:
- Height sensors mark correct temperature.
- Product does not reach temperature in low areas.
- The system works longer.
- Increases energy consumption.
Poor drive and return design can completely compromise system efficiency.
Common Pitfall 4 – Failure to properly remove cold air in steam systems
In industrial steam heating systems, the initial removal of cold air is critical.
If it does not exist:
- Suitable purge valve.
- Evacuation system at high points.
- Correct start-up design.
The air acts as a thermal barrier and prevents efficient heat transfer.
This detail can double the heating time without the problem being the installed power.
Common mistake 5 – Failure to correctly calculate the thermal losses of the enclosure.
Thermal losses in industrial rooms are often underestimated.
The main critical points are:
- Floors without thermal insulation.
- Metal walls without a suitable sandwich panel.
- Leaky doors.
- Uncontrolled air renewals.
The floor, especially, acts as a continuous thermal sink if it is not insulated.
In many projects, losses can represent between 20% and 40% of the total power required.
Common mistake 6 – Setting a target time without adjusting the power required
A common specification is: “The room must reach 70 °C in two hours“.
Reducing the heating time does not imply a linear increase in power. In many cases, to reduce the time by half it is necessary to significantly multiply the installed power.
Time is a critical design variable, not a guide parameter.
How to make a correct power calculation in industrial heating systems
A rigorous industrial thermal design should include:
- Confirmation of the actual volume built.
- Confirmation of thermal mass per cycle.
- Calculation of transmission losses.
- Stratification and recirculation analysis.
- Cold air elimination design.
- Clear definition of the target time.
Only when these factors are analyzed together is it possible to determine the actual thermal power required.
Conclusion – The problem is usually not the machine, but the thermal design.
When an industrial room does not reach temperature, it is rarely the fault of the generator.
Usually the problem is in:
- An incomplete calculation.
- Process changes not contemplated.
- Ignored thermal losses.
- Poor heat distribution.
Correct industrial thermal sizing is not about installing more power. It consists of designing the complete system taking into account the actual heat behavior.
Contact us and we will help you design the optimal solution for your installation.