When Is an Oil Smell an Emergency?
Heating oil is not natural gas. It does not explode from a spark the way gas can, so a faint oil smell in the basement is not a reason to leave the house. It is a reason to find the cause this week rather than next month.
Some oil smells are urgent. Shut the burner off at the red emergency switch, open windows and call the same day if the smell is strong and getting stronger, if it comes with smoke or soot anywhere in the house, if the burner banged or rumbled when it started, or if a carbon monoxide alarm has sounded. A burner that is misfiring badly enough to smell upstairs is a burner that can puffback, and the emergency heating repair page covers what that looks like.
Oil Smell Only When the Burner Starts
This is the most common one, and it points at the burner. A healthy burner lights the oil spray the instant it starts. A burner with worn electrodes, a cracked electrode porcelain, a tired ignition transformer or a nozzle spraying a bad pattern lights a second or two late, and in that second raw oil vapor is sprayed into a chamber with no flame. Some of it escapes past the burner and the draft regulator into the basement, and the house smells of oil for a minute after every cycle.
Delayed ignition often comes with a rumble or a small bang at startup. Left alone it leaves unburned oil in the combustion chamber and the smell gets stronger over the season. The fix is a $219 tune-up, which replaces the nozzle and checks the electrodes and ignition, or a service call if the burner has already started locking out.
Oil Smell That Never Goes Away
A steady smell with the burner on or off means liquid oil somewhere. Start at the burner and work back toward the tank:
- The oil filter canister, the cartridge housing on the line near the burner. A gasket that weeps leaves a wet ring and a dark stain on the floor below it.
- The fuel pump. A worn shaft seal leaves oil on the pump body and drips at the burner.
- Flare fittings and the oil line itself, especially copper line that runs along a floor where it can be stepped on or corroded by a damp slab.
- The tank. Indoor tanks weep at the bottom seam or at the outlet valve; the smell is strongest in the tank room. Outdoor and buried tanks show up as a smell near the fill pipe, oil-stained soil or a fuel smell in the yard.
A wet fitting or filter is a small repair from the truck. A tank that is weeping is a tank replacement, and the sooner it comes out the smaller the cleanup. Many Long Island tanks are the original 275-gallon steel tanks the house was built with, and a steel tank that has started to weep does not stop.
Oil Smell Right After a Delivery
A delivery fills the tank under pressure and stirs up whatever is in it. A loose fill cap or vent cap, a weeping fitting that was dry when the tank was low, or an overfill that pushed oil out the vent all show up in the hour after the truck leaves. Check around the fill and vent pipes outside and around the tank and filter inside for wet spots.
If the delivery was from our sister company, call and say so; if it was from another supplier, call them about an overfill and call us about the tank or the fittings. The heating oil delivery page explains how a Domino Fuel delivery works.
Oil Smell After a Puffback
A puffback is a small explosion in the combustion chamber, usually after several presses of the reset button have pooled unburned oil there. It blows soot and oil vapor out through every gap in the burner and smoke pipe, and on a warm-air furnace the ducts carry it to every room. The smell is heavy, the soot is greasy and black, and it settles on everything.
Shut the burner off and call for same-day service. The burner needs the cause of the misfire repaired and the chamber checked for damage before it runs again, and the house needs a proper soot cleanup, which is a separate job from the heating repair. The reset button guide explains why pressing it once and only once prevents most puffbacks.
Smells That Are Not Heating Oil
A burning dust smell for the first hour of the season is the dust on the heat exchanger burning off, and it clears on its own. A hot electrical smell is a motor or a wire and needs a look. A rotten egg smell is natural gas, not oil: leave the house and call the gas utility from outside, then call us once the line is safe. A musty smell from the ducts is moisture, not fuel.
The Service Call for an Oil Smell
The technician runs the burner and watches the start, checks the electrodes, nozzle and ignition, and reads the draft at the smoke pipe. Then the oil line is traced from burner to tank with a flashlight and a rag, because a weeping fitting leaves a mark long before it leaves a puddle. The worn part is replaced from the truck, the chamber is inspected if the burner has been misfiring, and the burner is fired and watched through a full cycle before the technician leaves.
The service call is $189 plus parts, each priced before it goes in. When the smell traces back to the tank, you get a free estimate for the replacement. The oil burner parts page lists the filters, pumps, valves and caps involved.
Related Reading
- Oil burner reset button: what it does and when to press it
- Why your oil burner keeps shutting off
- Choosing an oil tank removal contractor on Long Island
House Smells of Oil? Call Domino
Call (631) 867-2231 and describe when the smell comes and where it is strongest. A NORA-certified technician comes out the same day in most cases anywhere in Suffolk County, Nassau County or Queens, with the price quoted before the work starts.