Frequently Asked Questions

on Waste Oil Heating & Burners

What is waste oil?

Waste oil can quite literally be oil that is drained from a vehicle during an oil change or drained from a fast food deep fryer. Waste oils can also be used transmission oils, cooking and vegetable oils, hydraulic oils, used synthetic oils or bunker oil, etc.  Of course waste oil may also contain some water, diesel, petrol, glycol or anti-freeze from car heating systems, paper from oil filters and metallic particulates from engine abrasion.

What will it cost to heat with waste oil?

If you generate a sufficient supply of your own waste oil, the cost of heating with waste oil is ZERO. If you need to purchase some or all of your waste oil there are oil suppliers in all states (see the link Waste Oil Suppliers)

Where can I obtain waste oil if I do not generate it or do not generate enough to meet my heating requirements?

Because waste oil is truly a waste product that cannot be safely dumped into the ground, landfills or waterways, commercial entities that generate large quantities of waste oil must typically pay a third party for proper disposal. The cost of waste oil does not fluctuate with the cost of other petroleum products but rather is determined by one thing: The prerogative of the Oil Recycler, who is paid to pick up the waste oil, filters it and makes it available for resale (see the link Waste Oil Suppliers).

What is the heating value of a typical litre of waste oil?

A typical litre of waste motor oil contains minimally 11 kw-hr (33,000 BTU or 36Mj). Waste vegetable oil heating values vary depending on the vegetable source.

What about COMPARING ENERGY VALUES of common fuels as cost/Mj?


Town Gas 1.2c/Mj (average across SA, Vic & NSW)
LPG 4.2c/Mj ($1.20/litre)
Diesel 3.3c/Mj ($1.20/litre)
Waste Oil 0.8c/Mj ($0.30/litre)
Electricity 7.0c/Mj  Domestic rate Origin Energy 2013 (25c/kWhr)
Coal 1.2c/Mj ($400/tonne)  @ grade  35Mj/Kg
  •    Note: 100Mj is 28kW-hr is 94,781 BTU

  •    Note: Timber Pellets in Australia are around 18 to 20 Mj/Kg [3.0c/Mj]

Is there smoke or noxious odor when burning waste?

The  Kroll waste oil burner emits little odor and NO smoke, only a heat haze is visible. Our waste oil burners meet or exceed all EPA requirements when maintained correctly.

Can I install the boiler or heater myself?

All local codes must be met by the installer. The Kozy is usually installed by the purchaser in about 30 minutes. Hydronic & piped systems, check with your local plumbers & mechanical services.

How much soot is there in a boiler after about a week or two of operation on waste oil?

A typical cleanout of a 100kW boiler that has burnt 500 to 600 litres of waste oil will leave a bit over 1 litre of soot.

What sort of regular maintenance or service can I anticipate?

Maintenance typically consists of vacuuming residual ash and dust from inside combustion chamber access doors & heat exchanger galleries or tubes to maximize efficiency. Total time to clean averages less than 30 minutes. Yes, you will get your hands dirty. The reusable stainless steel oil filter(s) included with the burner does require periodic cleaning which can be quickly accomplished by rinsing in kerosene. The preheater heating rods should be examined for cleanliness. Rubbish inside the preheater should be cleaned out annually.

What are the most common problems with waste oil burners?

The most frequent complaints about competitor burners involve frequency of required cleaning and no ignition due to plugged nozzles. When your installation is performed correctly, and the normal maintenance is followed, you should have no problems or hassles, just inexpensive heat from your Kroll waste oil burning system!