Products Range
Process Heating > Thermic Fluid Heaters

Unitherm’s Thermic Fluid heaters operate in a closed loop heating system at near atmospheric pressure with temperatures as high as 2800C/3000 C. The system comprises of closed loop circulation of hot mineral oil through the user equipment for process heating and the return oil is reheated in the Thermic fluid Heater. The specially designed expansion and balancing tanks ensure pressureless and vapour free system.

For higher temperature applications, Unitherm’s customized Thermic Fluid heaters are available upto 3500C with Nitrogen blanketing.

These Thermic fluid heater are highly efficient with most designs having four distinct passes of flue gases. The Unitherm’s Thermic Fluid heaters are available in HORIZONTAL as well as VERTICAL construction with concentric helical coils placed inside sturdy M.S. shell having three or four distinct passes of hot gases.


Unitherm’s Thermic Fluid heaters are available in wide range of capacities from
30,000 Kcal/hr to 40, 00,000 kcal/Hr.

The Unitherm’s Thermic Fluid heaters are available in liquid fuel firing with,

  1. Diesel
  2. Furnace Oil
  3. Natural gas
  4. LPG firing
  5. Dual fuel firing - oil cum gas fired

Unitherm’s Thermic Fluid heaters are also available in solid fuel firing with, multifuel design which operate on most solid fuels, such as:-

  1. Indian & imported coal
  2. Lignite
  3. Fire wood
  4. Briquette

5 Pass Solid Fuel Fired Thermic Fluid Heaters.

Unitherm’s Thermic Fluid heaters are also available for use with most of the low calorific value fuels & waste such as:-

  1. Veneer waste
  2. Wood chips
  3. Saw dust
  4. paddy husk
  5. Baggasse
  6. Ground nut shells
  7. Cashew kernels
  8. Coconut shells
  9. Customized needs

A generously designed refractory lined external furnace is provided for solid fuel fired Unitherm’s Thermic Fluid heaters to ensure high furnace volume and grate area and can ensure rated output on multiple fuels without any modifications.

Unitherm’s Thermic Fluid heaters are also available with Electrical heating for special purpose applications.

Safety Features

Unitherm’s Thermic Fluid heaters are equipped with Adequate safety controls for safe operations & are equipped with

Fully automatic operation
Adequate safety controls  & instrumentations
Audio Visual Alarm in case of abnormal working conditions
Auto Cut off  of the combustion in case of abnormal operating conditions.

Salient Features

  • Fully automatic operation
  • Three  & Four Pass design, Maximum Fuel efficiency.
  • Multiple passes on Thermic fluid side ensure low-pressure drop across the coil, thereby making more head available for the process.
  • Can obtain temperature up to 280 deg C /300 deg C with low operating pressures.
  • Low System lag, rapid warm up response,
  • High Thermic fluid volume in the coil ensures adequate thermal storage and low heat flux.
  • Higher heat transfer area provided in the coil ensure low thermal stresses on the tube surface, and result in longer life of the coil as well as the Thermic oil.
  • Coil is made out of Boiler Quality, B.S.3059, 9 Gauge, TATA/TI make, ERW tubes for longer life and high temperature operation.
  • Designed with hinged doors for easy access on all sides of shell. Inspection doors are provided at strategic locations for easy inspection, Cleaning & Maintenance of Coil.
  • For solid fuel firing External bottom furnace with large combustion volume & high grate area is provided, which can easily burn most low-grade solid fuels like high ash Coal, lignite, Briquettes, wood, etc,
  • For solid fuel firing Specially designed, heat resistant fire bars made from close-grained cast iron give long operational life.
  • Specially designed expansion & balancing tanks are provided to avoid overheating of Thermic oil and releases excess pressure & vapours and ensure longer life of Thermic fluid.
  • For solid fuel firing, No direct impingement of flame on to the coil due to external furnace, hence no overheating or charring of Thermic oil, thereby increasing operational life.
  • For solid fuel firing ,By pass Chimney is provided with damper to safeguard against overheating and Charring of oil in case of power failure.
  • Outside the purview of I.B.R.
  • Completely safe operation with a number of safety features and instrumentation provided.