50 Years Of Trust | Engineering The Next Energy ERA
50 Years Of Trust | Engineering The Next Energy ERA
ISOTEX HTM Heaters — Unitherm Series — deliver ultra-precise, high-temperature heating using premium synthetic heat transfer medium fluids. Engineered for industries requiring contamination-free, stable process heat at temperatures up to 300°C with unmatched temperature uniformity and operational safety.
ISOTEX HTM Heaters — the Unitherm Series — are engineered for industries requiring the highest levels of temperature precision, thermal stability, and contamination-free indirect process heating using premium synthetic heat transfer medium (HTM) fluids. HTM systems deliver consistent, uniform process heat at temperatures up to 380°C with near-atmospheric operating pressure, combining operational safety with exceptional process repeatability.
Unlike mineral-oil-based thermal oil systems, ISOTEX HTM Heaters are specifically designed to operate with synthetic HTM fluids — including globally recognised brands such as Therminol, Marlotherm, Dowtherm, and Paratherm — offering superior thermal stability, longer fluid service life, and lower oxidation rates at high operating temperatures.
As a complete turnkey solution — from the oil/gas-fired burner and heat exchanger through synthetic HTM circulation system, nitrogen blanketing, expansion vessel, precision control, and SMARTWIZ IoT integration — every Unitherm HTM Heater is factory-assembled and commissioned before dispatch, ensuring rapid site startup and reliable long-term operation
ISOTEX Unitherm HTM Heaters are available across a comprehensive capacity range —Up to 15 Million Lac kCal/hr — engineered for precision synthetic HTM heating in high-value industrial applications.
| Parameter | Value / Range | Unit / Notes |
|---|---|---|
|
Heat Output Capacity |
Up To 15 Million |
kCal/hr |
|
Max. HTM Outlet Temperature |
Up to 380°C |
Standard — Synthetic HTM |
|
Temperature Control Precision |
±1°C |
At Design Flow Rate |
|
Thermal Efficiency |
Up to 95% |
On NCV Basis (BS 845) |
The ISOTEX Unitherm Thermosyphon Boiler is available in multiple firing configurations, offering unmatched fuel flexibility across solid, liquid, and gaseous fuels to match every industry’s availability, cost, and emission requirements.
Light Diesel Oil
Furnace Oil
High Speed Diesel
Light Hydrocarbon Fuel
Used in petrochemical-adjacent plants with naphtha availability; clean combustion with GCV ~10,500 kCal/kg — engineered burner system required for safe naphtha firing.
GCV ~3,000–3,200 kCal/kg
~2,100–2,400 kCal/kg (dry);
GCV ~3,200–3,800 kCal/kg
~4,200 kCal/kg
High-calorific agro-waste, from groundnut processing in Gujarat and Andhra Pradesh; excellent fuel quality with low ash content — ideal for hot oil systems near edible oil processing clusters.
GCV 3,800–4,500 kCal/kg
Densified agro-waste pellets (rice husk, mustard stalk, cotton stalk), automated feeding, clean combustion, and ease of storage — premium biomass fuel for solid-fuel hot oil systems.
GCV ~3,500–4,000 kCal/kg
GCV 4,500–5,500 kCal/kg
Imported thermal coal with consistent, low moisture, low ash — most widely specified coal grade for FBC and stoker-fired hot oil systems in chemical, polyester, and polymer plants.
GCV 3,500–4,500 kCal/kg
Domestic coal from CIL sources, (GCV basis); cost-effective fuel for large-capacity hot oil systems where biomass availability is limited — FBC combustion recommended for high-ash Indian coal grades.
GCV ~2,800–3,400 kCal/kg
Low-rank coal from Rajasthan and Tamil Nadu lignite fields, high moisture content requires FBC or dumping grate combustion — very low cost per kCal for plants in lignite-producing regions.
GCV ~2,800–3,400 kCal/kg
Char and coke by-products from steel and chemical plants; combustible industrial waste streams available at low cost — engineered combustion systems designed for high-fixed-carbon, high-ash solid fuels.
The Ecobloc introduces patented inbed heat recovery technology and advanced FBC combustion engineering that surpasses every conventional alternative in efficiency, fuel flexibility, and long-term reliability.
Explore ISOTEX Unitherm HTM Heater installations demonstrating proven performance across high-precision industries requiring synthetic heat transfer medium heating up to 300°C.
High-Capacity HTM Heater for Textile Industry in Gujarat
75 Lakh kcal/hr x 3 (350°C)
Heavy Oil / Natural Gas
HTM Heater for Polyester Industry in Gujarat
1.2 Cr kcal/hr x 2 (350°C)
Briquette
HTM Heater for Polyfilms Industry in Haryana
60 Lakh kcal/hr x 2 (330°C)
Gas
HTM Heater for Chemical Industry in India
17 Lakh kCal /hr (395°C)
LSHS
PDF — Full technical specs, HTM fluid compatibility guide, dimensions & selection table
Our engineering team responds within 24 hours. Share your capacity requirements and fuel preference. We’ll engineer the right solution.
