Multi / Waste Oil Heater – Manual Ignition

Waste oil drip heater – Output range 29kW / 98,948 BTU’s

W401K Manual Fired Stationary Heaters
Small waste oil heater – Experience gained over many decades makes the Kroll multi/waste oil heater a reliable, cost effective and an environmentally friendly heating product.Our W401 heater is a manual ignition, or vaporising waste oil heater- which are lower cost, simple to use and maintain and very robust.It is a vaporising heater which means it is drip fed so it does not require a compressed air supply.

In times of rising fuel costs, the pay back period for a Kroll multi /waste oil heater is very short. Utilising your waste oil, you get an effective warm air heater with no fuel costs, and no fees to pay for the collection and disposal of your waste oil. The W401 is our opinion is the best small waste oil burner UK wide. We have just supplied spares to a unit that is 45 years old ! a testament to the quality of this German made unit.

It has been commonly known for years that waste oils, have a calorific value ( or heating energy ) very similar to conventional heating oil. The secret has been to get the oil to burn safely,cleanly, and without any pollution and Kroll has been doing this for years with this unit, meaning that you get as much heat as you require , combined with virtually no running costs. These Kroll waste oil heaters run cleanly and more importantly efficiently on all engine oils , whether it be  hydraulic oil,sump oil, gear oil or transmission fluid. You can literally use it as it comes from your transmission or engine  from your machinery or vehicle, without the need for any special filtering.

The Kroll W401 small waste oil heater is particularly suitable  for heating automotive workshops and garages, warehouses, small greenhouses, etc.They are equipped with a  self contained oil tank of 25 litres and are easy to install, being instantly ready for use.

Can be supplied with our without a top mounted Thermo-blower to increase the throw of hot air .A high capacity axial fan draws air from the area over the heat exchanger and combustion chamber and expels the warm air into the building, providing a constant supply of warm air. The unit runs off a 240Volt supply.

Small Waste Oil Heater – Kroll Universal/Waste Oil Fired Heaters can be operated on the following fuels –

  • Used Oil , such as engine or gearbox oil (subject to licensing control)
  • 35/28 Second Heating oil/Diesel/Kerosene
  • Bio Diesel
  • Rapeseed Oil
  • Linseed Oil
  • Certain Vegetable Oils
  • Processed Fuel Oil ( PFO )

The 25L tank has got an integrated oil strainer and an electromagnetic gear pump to supply the burner basin with oil. The integrated overflow switch stops the electromagnetic gear pump automatically in the case of a fault, so no oil can leak

After ignition, an integrated thermostat switches on the cross-flow fan and the electromagnetic gear pump as soon as 55°C has been reached inside the combustion chamber

Installation of the W401 Kroll Multi / Waste Oil Heater –

The heater must be installed on a completely level, concrete floor.The positioning of the heater in the garage or workshop must be reliant on the following factors –

• A 240 Volt Electricity supply

• The Flue pipe installation

Can comfortably heat an area of 1,500 square feet/ 300 M²

Waste Oil Heater Maintenance on the Kroll W401 Heater / Small Waste Oil Heater

Well as the saying goes ” you get nothing for nothing in life “. The only thing you will have to give to any small waste oil heater , that is manual ignition , is a bit of your time. Firstly, this waste oil heater is a basic bit of heating equipment and not “high tech” in any form – by this we mean that you don’t have to be a heating engineer to use or maintain the heater. To start the multi/waste oil heater , you pour a cup of diesel or kerosene into the cast iron burner basin, which sits at the bottom of the heater , and then light it with a match. Then after approximately ten minutes the internal thermostat automatically starts the oil pump and the blower fan . Waste oil then trickles into the burner basin, where it  vaporizes into a gas and then is burnt very cleanly and efficiently resulting in the heater giving off no fumes or smoke via the flue pipe exhaust system. Any contaminants in your waste oil such as dirt,carbon or detergents are broken down in the 750 °C temperature of the combustion chamber , leaving a crusty dry ash which accumulates in the burner basin , which we recommend cleaning every day . taking about 5 minutes of your time.The amount of ash you will get will depend on the quality and cleanliness of your waste oil , but for example transmission oils leave almost no ash generally, very thick waste engine oil from oil diesel engines leave more ash . Generally , oils from petrol engines , or a combination of waste oils , gives you plenty of heat and very minimal ash.

What a lot of our customers do , is purchase another burner basin off us , so when they start the unit every morning , they use the clean one , then at a time convenient to themselves, they clean “yesterdays burner basin”, making it ready for use in the heater “tomorrow”.

I think you agree that these 5 minutes a day , is a small price to pay for the advantage of  warm air heating with free fuel ! 

Sometimes these heaters are referred to as waste oil workshop heaters,waste oil drip heaters,drip oil waste heater, small waste oil heater,small waste oil heater for a garage, with thousands sold since its conception , we believe we have the best Waste Oil Heater for sale on the market.

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  • 35kW nominal heat input
  • High delta T (80 kelvin)
  • High/ Low manual heat regulation
  • Flame failure safety feature
  • Manual ignition
  • Self-contained oil tank with option for external fuel supply
  • Heavy gauge steel casing with durable powder coated finish
  • Available with or without cross flow fan

Technical Data

Model   W401K
Nominal heat inputkW35
Nominal heat outputkW29
Air deliveryM³/h820
Temperature rise (∆T)kW80
Oil consumption *kg/h1.9 – 2.8
Electrical connectionV/A230/0.4
Electrical power consumptionkW0.09
Flue gas pipeØ mm150
Tank contentlitres24

Download the Operating and Maintenance Manual

Download the Spare Parts Diagram

Download the Wiring Diagram