
Industrial Electric Boilers – 15kW to 5MW

Electric Industrial Boiler Range – 30kW to 5MW Output
Industrial electric boilers are a highly efficient heating system for producing hot water for space heating and/or indirect domestic hot water. An electric boiler uses electric heating elements to generate thermal energy to heat water with high efficiency for space heating in industrial applications or to be used in industrial processes.These electric industrial boilers can also produce domestic hot water via an indirect calorifier.
There has been a large uptake in the popularity of these electric industrial boilers, as your hot water system, if powered by renewable electricity with no carbon emissions, can eliminate your reliance on fossil fuels and contribute to a clean and more sustainable environment with zero emissions.
An electric boiler is a perfect solution for heating and DHW production via an indirect water heater being relatively easy to install and don’t need any room for fuel storage / fuel supply via gas supply pipelines.
Please note these are high pressure hot water electric boilers (up to 6 Bar maximum) for industrial applications and are not an electric steam boiler, and this range is the next step up from our commercial electric boiler range, which can produce a water temperature of 90°C as standard (we cannot produce a higher water temperature than this) and up to 6 Bar water pressure.
If you require higher pressures, then you must make a primary circuit, and use a plate heat exchanger to separate the two systems, and thus the pressures. Like so

Boiler hydraulic separation for higher heating system pressures using a plate heat exchanger – a primary circuit is required which also allows for different temperatures between the boiler and the heating circuits.
We do not supply an electric boiler for steam production- i.e. a steam boiler
Industrial electric boilers have lower installation costs when compared to fossil fuel boilers, as no flue pipe installation is required to remove the products of combustion, as there aren’t any with a high efficiency electric industrial boiler.
All incoming electrical energy is transformed to thermal energy, resulting in an efficiency close to 100% in our industrial and commercial electric boilers.
These electric boilers can aid in reducing the environmental impact with zero emissions,as renewable energy sources produce an increasing amount of electricity that is CO2 neutral or better, unlike fossil fuels.
Industrial electric boiler efficiency
Electric boilers are generally regarded as having 100% efficiency, as all the incoming electrical energy that goes into the immersion heaters is converted into thermal energy to produce hot water.
Technically, there is an argument that they are 99.9% efficient overall, as there is a minute amount of electricity used to power the control panel on the electric boiler. Our industrial electric boilers are a reliable source of hot water for space and / or industrial processes heating system.
Advantages of Electric Boilers
- 100% efficiency of the immersion heaters in these electric-powered hot water boilers
- Robust construction for long-term operation of this industrial electric boiler range
- Easy installation and commissioning.
- You benefit from low servicing and maintenance expenses, when it comes to electric boilers, as they require less regular maintenance than a gas or oil boiler. Electric boilers have no moving components as such, whereas other types of boilers have more moving elements that may break down and need maintenance.
- There is no heat exchanger to block up, as there is no combustion chamber in an electric boiler. Electric boilers work by utilising immersion heaters, similar to those used in domestic hot water heaters, just on a larger scale.
- You can get away from fossil fuel as your energy heat source if you use renewable electricity (with zero emissions) and reduce or eliminate your carbon emissions.
- Environmentally friendly, with no combustion gas emissions produced.
- These electric boilers are designed for commercial and industrial heating systems, be they radiators, underfloor heating, or to generate heat for district heating schemes.
Boiler Product Range
- Power output from 30kW to 5 mW –This range of industrial and commercial electric boilers consists of eight models: a 120 kW, 150 kW, 180 kW, 210 kW, 255 kW, 300 kW, 400 kW, and a 500 kW electric boiler. With the ability to cascade up to 10 boilers of various sizes,the maximum kW output achievable is 5MW.
- Great boiler output modualtion range – 7:1 for the 120kW model, and 15:1 for the rest of the range.This energy saving feature allows close heating system load matching in a highly efficient manner.
- Operating temperature from 20°C to 90°C water temperature
- Maximum Delta T directly through the boiler is 20C and the minimum is 5C – Outside of these parameters please hydraulicly separate the heating system, with a primary heating circuit and a secondary circuit.
- Maximum operating hot water pressure: 6 Bar rated
- Required Voltage – 400 Volt Three-phase
- 50mm Glass wool insulation with sheet metal finish (MO fire classification)
- We use high quality screwed shielded Incoloy immersion heaters within our electric industrial boilers.
- Robust construction
- Safety temperature thermostat with manual reset set at 110°C, fitted as standard to the electric industrial boilers.

Themo Max electric boilers data table from 120kW to 500kW in single electric boiler models
Each boiler has multiple immersion heaters used within the boiler,which are either 12kW or 15kW in size, that are controlled in groups, giving a high 15:1 modulation ratio for all but our 120kW model, which has 7 power output stages, thus 7:1 for this size boiler

I.E Our Thermomax 400kW output industrial electric boiler showing the multiple immersion heaters used within the boiler, that are controlled in groups, giving a high 15:1 modulation ratio.
Modulation output steps of our Thermo Max industrial boilers powered by electricity
So, for example our 500kW boiler will ramp up and down the output scale of the 15 power steps from 30kW to 501kW which is great for high efficiency close heat load matching of the system.
However, the boiler can also be set to a maximum output for each of its power steps and will produce no more than that set level – i.e. If set on power stage 13 – which is 435kW of output, the boiler will ramp up and down the heating output scale to a maximum of 435kW (thus the turndown ratio in this example would then be 13:1).
This ensures that our commercial electric boiler range can cover many, many heat output requirements.
Electric Power and Controls Cabinet
Our standard control panel (“X” control panel) set up on our electric boilers is integral to the electric boiler, is a fully Modbus type and includes:
- Frost protection system – if the water temperature drops below 7 °C – the boiler automatically starts to raise the water above 7 °C and prevent freezing.
- Inputs:Two temperature sensors connections – one for connecting an external temperature sensor for weather compensation, the other is for an immersion sensor for control and production of sanitary grade hot water, via an indirect commercial hot water cylinder. Both of these optional sensors are available from us.Remote
- On/off signalSafety thermostats switch off.
- 0-10 Volt analogue signal for set point temp or percentage of power output
- Outputs:
- 0-10V temperature signal or percentage of power (power steps)
- Error signal
The Modbus TCP protocol uses an RJ45 connection and the Dynamic Host Configuration Protocol (DHCP), a client/server protocol that automatically assigns an IP address to an Internet Protocol (IP) host, along with other relevant configuration information such as the subnet mask and default gateway.

Modbus Control panel set up
Download the commissioning and maintenance instructions for the Thermo Max range of electric boilers
Accessories for our electric industrial boilers
Essential accessories required for our boilers are a water flow switch or pressure switches or a combined hi / low pressure switch to protect the boiler from low (1 Bar) or high (6 Bar maximum) pressure,pressure saftey valve set at 6 Bar, and a drain valve.
These can be fitted into the heating system, or alternatively the boilers have connections on them for this equipment.

Accessories required for our electric industrial boilers
Replacing a gas or oil fired boiler
Yes, it’s not an issue to replace your existing heating system boilers, with an electric boiler, you just need to have the Amps required on a three phase electricity supply to power these boilers.
Please contact us
If you need any further assistance, information, to check stock or to obtain prices on the best industrial electric boilers on the UK market, please contact our customer service sales team on 01202 822221 or use our email contact form.