It’s minus twelve on a January night in St. John’s, the wind is coming straight off the harbour, and the furnace just hummed for ten seconds and quit. Again.
If that’s you right now, take a breath. A furnace not getting oil is one of the most common heating calls on the Avalon every winter, and most of the time the cause sits somewhere on the short path between the tank outside and the burner in the basement. That path has only a handful of parts: the tank, a shutoff valve, a filter, a length of copper or steel line, and the pump on the burner. When oil stops moving, one of those is the culprit.
This guide walks you through seven checks in the order a service tech would do them. Some you can do yourself with a flashlight and five minutes. Others are a “put the tools down and pick up the phone” moment. We’ll tell you which is which.
First, Figure Out If the Furnace Isn’t Getting Oil or Just Isn’t Burning It
A furnace that won’t fire has two families of problems. Either oil isn’t reaching the burner, or oil is reaching the burner and something else (ignition, the nozzle, the cad cell eye, the control board) is stopping it from lighting. The symptoms look almost the same from the top of the basement stairs, so it helps to listen.
A burner that’s starved for oil usually runs its motor for a bit, sputters, maybe puffs, and then locks out. You’ll hear the pump whining and nothing catching. A burner with an ignition problem often gets a flame that’s dirty or short, or it fires and cuts out fast with a smell of unburned oil.
Here’s the simple rule: if you smell raw oil in the basement, stop pressing buttons. That’s oil reaching the chamber and not burning, and every extra reset adds more. Leave it and call your furnace tech.
No oil smell, no flame, pump pulling on nothing? Keep reading. The next seven checks go from the tank inward.
One exception before you start. If the lockout comes with a delivery driver’s refusal slip, or a tank that’s past the expiry stamped on its HOST tag, skip the checklist and call us at (709) 800-3117. That’s a different problem with a different fix, and the 24/7 line exists for exactly those nights.
Seven Things to Check When Your Furnace Isn’t Getting Oil
Work through these in order, from the tank toward the burner.
1. Trust the stick, not the gauge
The float gauge on top of a steel tank sticks, reads high, and lies more often than you’d think, especially on an older tank with sludge in the bottom.
Pull the gauge cap (it unscrews by hand on most tanks), slide a clean, dry length of dowel or a metre stick straight down to the bottom, and read the wet line. On a standard 200-gallon tank, anything under about 10 centimetres means the pickup tube may be sucking air, even though the tank isn’t bone dry. If the gauge said a third and the stick says empty, you’ve found your problem, and you’ll want to read why oil tank gauges stop working before you trust it again.
Dave in Kelligrews learned this the hard way last February. His gauge sat at a quarter all week. The furnace cut out on a Sunday night and the stick came up dry.
When the delivery driver arrived Monday he took one look at the HOST tag, stamped 12-2025, and had to refuse the fill. Dave had a fibreglass tank installed that week for $3,850, old tank hauled away in the same visit, and a new tag that’ll outlast his mortgage.
2. Press the reset button once, and only once
Every oil burner has a reset button, usually red, on the primary control. If the burner locked out for a small reason (a bubble of air, a brief power flicker), one press will often bring it back.
Press it once. If the furnace fires and stays lit, good. If it fires and dies again, or does nothing, leave it alone.
Repeated resets pump raw oil into the combustion chamber. When it finally lights, you get a hard start that can crack the chamber or blow soot through the house. One press is a check. Three presses is a mess.
3. Find the shutoff valves and make sure they’re open
There’s a valve at the tank outlet and usually a second one, called a firomatic or fusible valve, right at the burner. Movers, a plumber working on something else, or a well-meaning relative can leave one partly closed.
Follow the line from the tank. Every valve handle should be in line with the pipe. A handle sitting crossways is closed. Open it slowly.
The firomatic valve at the burner is spring-loaded to snap shut in a fire, and a bump can close it too. If it won’t stay open, don’t force it; that’s a part that needs replacing, not persuading.
4. Check the filter for sludge
Between the tank and the burner sits a canister filter, a small housing on the line near the burner. Its job is to catch water, rust flakes and the black sludge that grows in the bottom of an aging steel tank. When it clogs, oil slows to a trickle, the burner starves, and you’re here reading this.
If you’re handy, closing the tank valve, dropping the bowl, swapping the cartridge and bleeding the air at the pump is a half-hour job, and our filter change walkthrough shows every step. If you’re not, call your furnace tech; they’ll bleed the line properly and check the nozzle while they’re at it.
Marg in Paradise had her furnace shut down three times in one December. Each time a tech changed the filter, it ran for a week, then choked again. On the third visit the tech drained a jar of oil from the tank bottom and it came out like coffee grounds.
Her tank was a 14-year-old outside steel unit with a tag due to expire the next spring, and the sludge was never going to stop. She replaced it with a 200-gallon painted steel tank for $3,200, removal of the old one included, and her filters have been clean since.
5. Look for gelled oil or a frozen line outside
Furnace oil starts to thicken in hard cold (the industry word is “gelling”), and wind makes it worse. An outdoor tank on the north side of a house in Torbay or Portugal Cove, with a thin copper line running exposed along the foundation, is the classic setup. Any water that got into the line freezes long before the oil does.
Signs: the furnace ran fine yesterday, the cold snap arrived, and now the pump is whining. If the problem clears up on a mild afternoon and comes back at night, you’ve likely got a gelling issue. Heating oil gelling in cold weather explains what a fuel supplier can add to the oil and how a line can be re-routed or insulated.
Do not put a torch, a heat gun or a space heater on a fuel line. Warm the basement end of the line gently, wrap the exposed section, and call your supplier about a winter blend. The long-term fix is usually moving the tank, the line, or both.
Pat in Torbay had a north-wall tank that gelled every January without fail. She’d already put in a heat pump and only burned oil on the coldest nights. Rather than fight the same line every winter, she had the outside tank removed and a 100-gallon steel tank set up inside the basement for $3,100, which covered the new tank, the install and the old one going away. No exposed line, no gelling, no January phone calls.
6. Check for air leaks and a wet spot along the line
An oil pump is a suction pump. Any fitting between the tank and the burner that’s loose, cracked or corroded lets air in, and air in the line means the pump pulls froth instead of fuel. The burner will run, sputter, lock out, reset fine, then do it again in an hour.
Walk the line with a flashlight. You’re looking for a damp, dark stain at any joint, a drip on the floor under a fitting, or a green crust on copper. Check where the line goes through the foundation wall, because that’s where salt air and frost heave do their work.
Here’s where DIY stops. A weeping fitting on a fuel line isn’t a tighten-it-and-see job. If you find oil on the floor, oil pooling under the tank, or a line corroded through, shut the tank valve, stop, and call. A drip today is a spill next month, and cleanup costs far more than the fix.
7. Read the HOST tag, because it may explain everything
This is the check almost nobody thinks of, and on the Avalon it’s the one that turns a “no heat” night into a week-long problem. Every registered tank in Newfoundland and Labrador wears a metal HOST tag with a six-digit number and an expiry stamped as month and year. A tag reading 7-2028 means the tank can’t be used after July 31, 2028.
Why does that matter when the furnace isn’t getting oil? Because if your tank is expired, or close to it, the delivery you’re waiting on may not come. Under the province’s Heating Oil Storage Tank System Regulations (NLR 60/03), a driver can’t deliver to a system without a valid registration label, and they have to report it. Plenty of “my furnace isn’t getting oil” calls are really “my tank is empty because the driver couldn’t fill it.”
Go outside with a flashlight and read the tag. If it’s expired, or expires this heating season, the fix isn’t a filter or a reset. It’s a new tank, and it’s the kind of thing you want done before the next cold snap, not during it. Our expired oil tank emergency service exists for that exact call.
If you’ve gone through all seven and you’re still standing in a cold basement, send us a note or call the line. We’ll tell you straight whether this is a furnace tech’s job or a tank job.
What It Costs to Fix a Furnace That Isn’t Getting Fuel
Costs run from nothing to a new tank, depending on which check turned up the problem.
| What you found | Who fixes it | What it usually costs |
|---|---|---|
| Gauge lied, tank is empty | You and your oil supplier | A delivery, if your HOST tag is valid |
| Lockout cleared with one reset | You | Nothing |
| Valve was closed | You | Nothing |
| Clogged filter | You or a furnace tech | Cartridge plus a service call, priced by your tech |
| Gelled oil or frozen line | Fuel supplier, furnace tech | Winter blend or line work, priced by the supplier or tech |
| Air leak, weeping fitting | Furnace tech | Fitting or line repair, quoted after they see it |
| Tank past its date, refused delivery | Tank installer | 200-gallon steel installed $3,200; fibreglass $3,850; both include removing the old tank |
| Old outside tank, heat pump home | Tank installer | 100-gallon steel installed $3,100 |
| Removal and disposal only, outside tank | Tank installer | $500 |
The tank figures are published Atlantic Canada retail prices for a straightforward install; your written estimate is what counts. And if the tank is the problem, the filter and line problems usually come with it, because sludge and corrosion grow from the same aging steel.
When to Stop and Call Someone
Most of this list is safe for a homeowner. These situations aren’t. Put the tools down if:
- You smell raw oil in the basement after a reset, or see oil in the combustion chamber.
- There’s oil on the floor, oil under the tank, or a wet stain spreading on the foundation.
- The tank is rusted through, bulging, or leaning on its stand.
- The line is frozen and you’re tempted to warm it with a flame.
- The HOST tag is expired, missing, or unreadable.
- You’ve reset the burner twice and it still won’t stay lit.
A furnace tech handles the burner, the pump, the nozzle and the controls. A tank installer handles the tank, the stand, the line and the tag. Some outfits do both; many don’t.
If you’re not sure which you need, call us at (709) 800-3117 and describe what you found. We’ll point you the right way even if it’s not our job, because the last thing you need on a cold night is a second wrong call.
If it is a tank, we’ll come out, look at it, and give you a free written estimate before anyone touches anything. You can see what a full tank replacement in St. John’s involves, from the first visit to the new tag.
Frequently Asked Questions
How do I know if my furnace is not getting oil or has another problem?
Listen and smell. A burner starved for oil runs the pump, sputters and locks out without a real flame, and there’s no strong oil smell. A burner with an ignition or nozzle problem usually gets some flame or leaves a smell of unburned oil. If you smell raw oil, stop pressing reset and call a furnace tech.
Can I press the furnace reset button more than once?
Press it once. If the burner fires and stays lit, you’re done. If it doesn’t, a second press only pumps more oil into the chamber, and a delayed ignition can crack the chamber or send soot through the house. Leave it and call a tech.
Will a delivery driver fill my tank if the HOST tag is expired?
No. Newfoundland and Labrador’s tank regulations bar delivery to a system without a valid, unexpired registration label, and the driver has to report it. If your tank runs dry and the tag is out of date, the fix is a new tank, not a delivery. We take those calls around the clock.
Why does my furnace keep clogging its filter?
Usually because the tank is making sludge faster than the filter can catch it. Water condenses in a half-empty steel tank, rust forms, bacteria grow where the oil meets the water, and the mess settles to the bottom right where the outlet pulls from. On a tank near or past its regulated life, a new tank is the only fix that lasts.