Top 6 Industrial Electric Heater Manufacturers in 2026
Six brands that supply industrial and explosion-proof electric heaters, compared on origin, range and hazardous-area offer, with the checks that matter before you ask for a quote.
The six brands at a glance
Two of the six share an owner: Spirax Group owns both Chromalox and Vulcanic. Caloritech is the process-heating brand of Thermon. EXHEAT, Runkel and Watlow are covered one by one below.
| Brand | Founded | Based in | Core range | Hazardous-area offer |
|---|---|---|---|---|
| Caloritech (Thermon) | 1954 | Austin, Texas, USA | Process heaters, electric boilers, heat tracing | Ruffneck explosion-proof unit and convection heaters. Not every Caloritech model is hazardous-rated. |
| Chromalox | 1917 | Pittsburgh, Pennsylvania, USA | Industrial heaters, heat tracing, packaged systems, controls | Ex d and Ex e heaters for Zones 1 and 2, per a UK distributor listing. |
| EXHEAT | Not verified | United Kingdom | Hazardous-area heaters and controls | ATEX, UKEx and IECEx products: enclosure, air, immersion and portable fan heaters. |
| RunkelPublisher of this guide | 2015 | Qingdao, China | Explosion-proof, circulation, bundle and duct heaters; tubular elements; PTC; cartridge heaters | Explosion-proof series, rated by model. Circulation units up to 3,000 kW. |
| Vulcanic | 1973 | Neuilly-sur-Marne, France | Immersion, flow and air duct heaters, cables, controls | ATEX immersion heaters, flow heaters and radiators. |
| Watlow | 1922 | St. Louis, Missouri, USA | Heaters, sensors, controllers, system assemblies | Not detailed in the sources we checked. Ask for model-level certificates. |
Scroll sideways on a phone to see every column. “Not verified” means we could not confirm the detail from the sources listed at the end of this page.
Caloritech (Thermon)
- Parent company
- Thermon Group Holdings
- Founded
- 1954
- Based in
- Austin, Texas, USA
Caloritech is the process-heating brand of Thermon, a US company best known for heat tracing. Thermon’s Ruffneck line covers explosion-proof electric unit heaters and convection heaters built for oil and gas sites, and the Caloritech name also appears on electric boilers.
Best fit: North American process-heating projects that also need heat tracing from the same supplier.
Check first: some Caloritech models, such as the BX convection heater, are not intended for hazardous locations. Confirm the certification of the exact model you plan to buy.
Chromalox
- Parent company
- Spirax Group
- Founded
- 1917
- Based in
- Pittsburgh, Pennsylvania, USA
Chromalox is one of the oldest names in electric heating. Its first product was a strip heater, and it has been part of Spirax-Sarco, now Spirax Group, since 2017. It sells industrial heaters, heat tracing and packaged heating systems. UK distributor listings describe Ex d flameproof and Ex e increased-safety heaters for Zone 1 and Zone 2.
Best fit: large projects that want packaged systems and controls from one global brand.
Check first: lead time and local service cover for custom units, which can vary by region.
EXHEAT
- Founded
- Not verified
- Based in
- United Kingdom
- Certification listed
- ATEX, UKEx, IECEx
EXHEAT builds hazardous-area electric heating and control equipment in the UK. Its catalogue runs from small enclosure heaters and air warmers to tank immersion heaters and a portable fan heater, with ATEX, UKEx and IECEx certification listed through its UK distributor.
Best fit: smaller hazardous-area jobs, such as cabinets, workshops and compact tank heating, where UK or European certification is required.
Check first: the sources we used did not confirm EXHEAT’s founding year or ownership, so verify both directly with the company.
Runkel
- Group
- Yangzhong Sanhuan Electric Heating Group
- Founded
- 2015
- Based in
- Qingdao, China
- Quality system
- ISO 9001:2015
Runkel Electric Heating was set up in 2015 as the foreign-trade arm of the Yangzhong Sanhuan group and works with group plants in Yangzhong, Shijiazhuang and Shenyang. Its 2026 brochure lists explosion-proof, circulation, bundle and duct heaters, food-grade explosion-proof heaters, tubular and liquid heating elements, PTC heaters, cartridge heaters, flexible ceramic heaters, bolt heaters and tube-production machines.
Circulation heater units are listed at 380 V up to 3,000 kW, and high-temperature duct heaters from 10 to 3,000 kW at 220 to 380 V.
Best fit: buyers who want a China-based maker to engineer custom explosion-proof, circulation or duct heaters to a specification, with price as a deciding factor.
Check first: the certificates shown in Runkel’s brochure are issued to group manufacturing companies, so request the one that names your model, zone and temperature class.
Vulcanic
- Parent company
- Spirax Group (since 2022)
- Founded
- 1973
- Based in
- Neuilly-sur-Marne, France
Vulcanic has made electric heating and cooling equipment since 1973. Its range includes immersion heaters, flow heaters, air duct heaters, heating cables and controls, with ATEX versions of the immersion and flow heaters. Spirax Group agreed to buy it in 2022, so it now sits alongside Chromalox.
Best fit: European sites that need ATEX-marked immersion or flow heaters.
Check first: the notified body and certificate number printed in the ATEX marking of your model.
Watlow
- Founded
- 1922
- Based in
- St. Louis, Missouri, USA
Watlow designs industrial heaters, sensors, controllers and system assemblies. That mix of heating and control hardware suits projects that need the whole thermal loop from one supplier.
Best fit: equipment makers and process lines that need heaters matched with sensors and controllers.
Check first: the sources we used did not detail Watlow’s hazardous-area range, so ask for model-level certificates.
How to choose an electric heater manufacturer
Start with the hazardous area. The zone tells you how often an explosive gas atmosphere is present, and it sets the protection type and certificate you need.
- Zone 0 More than 1,000 hours a year Explosive gas is present continuously or for long periods.
- Zone 1 10 to 1,000 hours a year Explosive gas is likely to appear in normal operation.
- Zone 2 0.1 to 10 hours a year Explosive gas is not expected in normal operation and, if it appears, is brief.
| Protection type | Ex d flameproof, Ex e increased safety or another type, matched to the zone and the heater design. |
|---|---|
| Certificate | ATEX, IECEx, UKEx or the national scheme of the destination country. It should name the exact model, not just the product family. |
| Medium and temperature | What is being heated, the target temperature, the working pressure and the temperature class required. |
| Power and supply | Total kW, supply voltage, phases and the number of heating stages. |
| Protection devices | Overcurrent, overvoltage, phase-loss and over-temperature protection, and whether the heater connects to a DCS. |
| Documents and support | Drawings, test reports, lead time, spare parts and who handles site questions. |
Frequently asked questions
Who are the top industrial electric heater manufacturers in 2026?
This guide compares six brands: Caloritech (Thermon), Chromalox, EXHEAT, Runkel, Vulcanic and Watlow. They are listed alphabetically rather than ranked, because the best fit depends on hazardous-area rating, power range, region and budget.
What is the difference between Ex d and Ex e electric heaters?
Ex d (flameproof) heaters use an enclosure that can withstand an internal explosion and stop it igniting the atmosphere outside. Ex e (increased safety) heaters add design measures that prevent arcs, sparks and excessive temperatures during normal operation.
Do Chromalox and Vulcanic belong to the same company?
Yes. Both are owned by Spirax Group, which bought Chromalox in 2017 and acquired Vulcanic in 2022.
What should I ask a manufacturer before buying an explosion-proof heater?
Ask for the certificate that names your exact model, the hazardous zone and temperature class it covers, the maximum medium temperature and pressure, and the protection devices fitted. Also confirm lead time, drawings and spare-part support.
Send us your heater specification
Share the medium, target temperature, power, voltage and hazardous zone, and Runkel’s engineers will reply with a proposal and quotation.
Email info@runkel.cn- Telephone
- +86 13360463744, +86 13904545333
- info@runkel.cn
- Address
- 46th Floor, Qingdao Wanbang Center, No. 2 Hong Kong Middle Road, Shinan District, Qingdao, Shandong Province, China
Sources and method
Facts were checked in October 2026 against the pages below and Runkel’s own 2026 product brochure. Company details can change, so confirm them with each vendor.
- Runkel Electric Heating, 2026 product brochure: company background, product series and technical parameters.
- Chromalox, Inc. on Wikipedia: founding year, headquarters and the 2017 Spirax-Sarco acquisition.
- Chromalox hazardous-area heaters at Thorne & Derrick: Ex d and Ex e heater listing.
- EXHEAT MTH listing at Thorne & Derrick: UK manufacture and ATEX, UKEx and IECEx certification.
- EXHEAT FAW listing at Thorne & Derrick: air warmer range.
- Thermon Group Holdings company profile: founding year, headquarters, Ruffneck and Caloritech brands.
- Caloritech BX datasheet on GlobalSpec: not intended for hazardous locations.
- Vulcanic profile on PitchBook: founding year and headquarters.
- Vulcanic on DirectIndustry: product range and ATEX offer.
- Spirax-Sarco announcement, July 2022: agreement to acquire Vulcanic.
- Watlow on Wikipedia: founding year, headquarters and product scope.