Frequently-asked questions and answers about why an oil burner will not start or will not keep running when it should.
This article series describes how to recognize common oil-fired heating appliance operating or safety defects, and how to save money on home heating costs
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This article series explains the inspection, diagnosis, & repair of oil burners used in heating appliances such as hot water boilers, steam boilers, & water heaters.
These questions about troubleshooting oil burners were posted originally
at OIL BURNER WONT RUN - you definitely want to review the diagnostic suggestions given there.
If your heat is not working properly, and the problem does not seem to be the oil burner itself, see NO HEAT - BOILER - hot water or steam heat
or
see NO HEAT - FURNACE - forced warm air heat
On 2018-04-15 by (mod) - Weil McKlain oil boiler/ Becket Burner / Webber
Curious, yes. Often I find
- clogging oil filter - you'll see the system trying to start and unable to get fuel
- air leaks in the oil piping - you'll see a sooting problem and maybe a PUFFBACK explosion at startup
- a failing ignition transformer (weak spark) - there are some crude as well as fancy ways to test the transformer
A good place to troubleshoot is at
On 2018-04-15 by Mike - Boiler would run for a few days and then trip reset
Weil McKlain oil boiler/ Becket Burner / Webber
Pretty old unit, but has been serviced and run fairly well- just changed burner nozzle- Boiler tripped reset- I changed nozzle and bled out air from line ( tank was getting low) - filled tank.
Boiler would run for a few days and then trip reset - reset and ran a few more days and tripped again. Now it’s down to only running an hour or two before reset trips.
Puzzled over what the problem actually is here
On 2017-12-19 by (mod) - Peerless boiler it. Lights flicker on low water
If this is a steam boiler and water level is too low - perhaps from a water feed problem, the oil burner gun won't ignite as the low water cutoff (LWCO) is shutting it down.
On 2017-12-18 by Robert
When I turn the switch on my Peerless boiler it. Lights flicker on low water in and the gun and goes off and won't start what can be the problem
On 2017-12-30 by (mod) - oil burner needs cleaning, nee nozzle, oil filter, and adjustment.
Your oil burner needs cleaning, nee nozzle, oil filter, and adjustment. Do not keep trying to re start it
On 2017-12-30 by jim - grizzle on the oil burner electrodes
what would cause this please?
build up of grizzle on electrodes stops ignition
On 2017-12-20 by (mod) - random refusal of burner to kick on
Yes that sounds like a failing control relay in the primary control or the aquastat
On 2017-12-20 by Jeff D
My oil furnace sometimes and only sometimes randomly will not kick on at all. I turn the power off for a minute than back on. It comes right on. I'm thinkinking a relay or something.
On 2017-12-08 by Willie
How to set fuel mix and air mix
On 2017-12-06 by (mod) - where to find step by step diagnostics if an oil burner won't run
Vanessa,
When an oil burner won't start or won't run, and when I have no other information about it, my best advice is to try going through the flow chart of diagnostic steps in the article above on this page: OIL BURNER WONT RUN
Keep in mind that a normal homeowner does not have the tools nor training to diagnose nor to properly adjust an oil burner, so once you've checked the obvious points like: have electrical power to the system, have oil in the tank, tried the re-set button ONCE only, then it's time to call your oil heat service company.
On 2017-12-06 by Vanessa Mitchell
Am disabled new oil filter and have prime buy burner still want come on
On 2017-12-02 by (mod) - Ducane oil furnace only runs when hit reset button twice.
Check also all of the things a service tech would review like fuel unit strainer, combustion air, flame smoke level, oil line leaks, draft.
Sometimes the reason you have to press the RESET button more than once is that on your first try you have not waited long enough since the primary control shut down the oil burner.
The primary control reset switch needs to cool down, often for several minutes, before it will allow you to reset-it.
See these Ducane furnace manuals that might help you out
You can also contact Ducane
On 2017-12-02 by Shaun
I have a Ducane oil furnace and it will only run when I hit the reset button twice. So after hitting it twice it's fine until the next turn on. I've changed the filter and nozzle with no luck so far.
On 2017-11-29 by (mod) - oil burner is spraying fuel - turn it off immediately
Peter
Watch out: you describe a dangerously improper operating oil burner. Turn it OFF and leave it OFF while calling your oil company for service/repair.
Typical causes: dirty oil burner nozzle, displaced flame head turbulator
On 2017-11-29 by Peter
The jet is still spraying fuel and the flame ignites a long distance in from the nozzle. The problem is that the flame does not stay going it pulses on and off and then trips out completely. What could be the cause of this?
On 2017-11-19 by Anonymous
Won't stay on when running
On 2017-11-11 by Rick
My home heating oil burner is starting. But when it knocks off an going to kick back in for the second time its like its going blow wit a niose wonder what it could be
On 2017-10-30 by Terry
What is the problem when u push the turn on bottom but the boiler goes off and won't stay on? Also whats the problem when I need a plumber because no water is in the radiator, what is the problem?
On 2017-09-27 by (mod) -
If one radiator is hot then the boiler surely has been running.
Your plumber might be right that pipes are clogged somewhere but tracing the route of pipes can help sort that out: if the hot radiator is *past* the cold radiators in the direction of hot water flow in the system then something else is wrong - perhaps air-bound radiators.
I would start by searching InspectApedia for AIR BOUND RADIATORS or search for COLD RADIATORS to see the suggested diagnostic and repair steps. It may be as simple as beeding air out of your radiators and piping when the boiler is up to temperature.
But I'm not one to ignore your observation about the new towel rail: pull the screws, inspect the screw holes to see if there was a wire (perhaps a thermostat wire) that got punctured.
On 2017-09-27 by Angie
There isn't a light on restart button on our oil boiler. Water in all rads but only one gets hot upstairs, all others stay cold.
Boiler starts initially, but after a minute or two switches off. We had a new towel rail fitted in bathroom and it's since then that we have this problem. Plumber says we need to have a system flush. Any help appreciated.
On 2017-08-28 by (mod) - yellow sludge coming out of oil pipe and boiler won't fire up
Al
I'm not sure what "oil pipe" you refer-to, but from what you describe there may be an unsafe chimney as well as oil burner.
Watch out: I would leave the system OFF and call for repair by an oil heat service technician. Let me know what you're told and we may be able to suggest additional questions to ask the service tech or things that need attention.
On 2017-08-28 by Al astair
There is a thick yellow sludge coming out of oil pipe and boiler won't fire up
On 2017-08-24 by (mod) - manuals and help fdor Grant Boilers sold in the U.K.
Simon,
I suspect that the sensor for the thermostat is either defective or it's not making good thermal contact with the boiler surface or well used to monitor boiler temperature.
Here's an example, though this is not the control on your Grant boiler: AQUASTAT L7224U UNIVERSAL inspectapedia.com/heat/Aquastat_Honeywell_L7224U.php
discusses the problem of poor temperature sensor contact in the sensor's insertion well on a boiler. Some technicians omit the thermal-conductive grease that is required.
If I'm right that you're using a U.K.-made Grant Boiler, you can also contact the company directly to get the installation, operation, and service manual for your boiler or to ask their technical support team for help.
You didn't give me a model name/number, but we provide access to Grant's boiler manuals at
GRANT BOILERS Grant Euroflame
On 2017-08-24 by Simon
Hi, have a grant boiler, unless the thermo attached to the boiler is on 85 degrees, tgevburnervwill not fire up?
Is this a fault with the thermo?
Cheers
On 2017-04-15 by (mod) -
Rick,
The soot situation is good evidence that the system is not working properly and is unsafe, perhaps risking an OIL BURNER PUFFBACK explosion - use the box above to search Inspectapedia for that phrase.
There are a variety of possible causes: improper set-up, combustion air, nozzle, electrode settings, chimney draft, etc.
Sometimes during work on an oil burner some oil is spilled by the worker - in the combustion chamber. Igniting that unburned oil is always scary and can cause an OIL BURNER PUFFBACK explosion; use the search box just above to look for that article to see details.
But if there is a chronic problem such as oil leaks, bad burner shutdown cycle, or other causes of sooty operation, then the smoky conditions will continue.
Shut such systems down and call for repair to avoid worse trouble.
On 2017-04-15 by (mod) - I got an oil burner on the internet - it smokes badly
Delaney
As my much smarter friend and Tampa inspector Mark Cramer says, " well, .... it depends"
If the leak loses enough water the boiler could be damaged or even become unsafe, a condition more likely if other safety features such as a temperature relief valve or a low water cutoff (not on most residential boilers) is missing or fails.
In any event the boiler SHOULD be shut down and most likely needs replacement.
On 2017-04-15 by Rick
I replaced my friends oil burner unit with one I got through the internet. It starts up and smoked really bad for a little while but did clear up, After a day or so they dad to shut it down because thier little white dog was turning black with soot. What do you think the problem is?
On 2017-04-15 by Delaney
Oil boiler water jacket split and leaking. Will this stop the central heating from coming on?
On 2017-04-15 by (mod) re: I replaced an oil burner but the new one smokes badly
Rick,
The soot situation in the new oil burner case you describe is good evidence that the system is not working properly and is unsafe.
There are a variety of possible causes: improper set-up, combustion air, nozzle, electrode settings, chimney draft, etc.
Sometimes during work on an oil burner some oil is spilled by the worker - in the combustion chamber. Igniting that unburned oil is always scary and can cause an OIL BURNER PUFFBACK explosion; use the search box just above to look for that article to see details.
But if there is a chronic problem such as oil line or nozzle adapter leaks, a bad burner shutdown cycle, air leaks in the oil piping, or other causes of sooty operation, then the smoky conditions will continue. And little white dogs become little gray or even black dogs.
Such oil burner systems should indeed be shut down and the homeowner should call an experienced, trained oil heat service technician for repair to avoid worse trouble.
While I congratulate you for trying to be a generous help to your friend - by replacing their oil burner - in my OPINION, unless you're trained and equipped as an oil heat service technician it is impossible to set up a new oil burner correctly and safely. That's because in addition to knowing where various parts go, the heating system's draft, combustion air, oil line pressure, temperature, CO, CO2 are all measured along with smoke as part of proper oil burner setup.
With older 1725 rpm oil burners one could eyeball the flame, spit on the flue (sizzle rate told old timers if the temperature was in range), and get the burner working acceptably - often. But newer high speed (3450 rpm) more efficient oil burners require equipment, measurements and adjustment for proper operation. Spitting doesn't work any more. I've given it up.
On 2017-04-15 by Rick
I replaced my friends oil burner unit with one I got through the internet. It starts up and smoked really bad for a little while but did clear up, After a day or so they dad to shut it down because thier little white dog was turning black with soot. What do you think the problem is?On 2017-04-15 by (mod) re: oil fired heating boiler split and is leaking water
DelaneyOn 2017-04-15 by Delaney
Oil boiler water jacket split and leaking. Will this stop the central heating from coming on?On 2017-03-27 by (mod) re: signs of a bad oil burner motor or control or electrical shorts
This sounds like a failed control or perhaps a motor bearing. To avoid a dangerous puffback explosion it's best to leave the system turned OFF and to call for professional repair.On 2017-03-27 12:25:56.710143 by Bonnie McCartney
I push the reset button and you can hear the electrical power jumping from the transformer, but it won't fire up until I tap it with a hammer on the pump or motor. It will run a cycle or two but then it will not come back on until I push the reset button and hit it again with hammer.On 2017-03-24 by (mod) re: pussing the reset button repeatedly
"Second time" on reset means that there is either a failing control or more-likely a poorly-operating burner that's causing the cad cell to shut down the system.On 2017-03-24 by Beckett 7505 burner won't start second time
So my burner will not fire for a second time when either my aquastat or t stat are calling for heat / hot water I use the shut off and click it back on and either or both will fire and work for one cycle and then an hr later the t star will call for heat and I would have to repeatOn 2017-03-16 by (mod) re: the oil burner fuel unit bypass plug
Mike:On 2017-03-16 by Mike
Installed new oil furnace & Beckett Burner. Have replaced bypass plug, oil pump, primary control, removed compression fittings, and put device on burner to adjust drip rate. Furnace has run no more than a day at a time, 2 oil leaks from burner. Burner is " new technology" type. What next?On 2017-03-11 by (mod) re: oil burner keeps going off on reset
Anon:On 2017-03-11 by Anonymous
Hi Gentlemen,On 2017-03-04 18:18:36.684426 by (mod)
Unclear what's the questionOn 2017-03-04 02:26:37.435056 by Anonymous
No oil on oil filterOn 2017-02-26 by (mod) re: boiler turned itself off, now what?
First confirm that there is power to the boiler
Next confirm that all boiler on-off switches are "ON"
Then find and press the reset button on the primary control ONE TIME
On 2017-02-26 by Sue
Hi my boiler has switched off ( No lights are on) I have checked indoor thermostat that light is working, i have checked the digital box where you can programme stuff and tried everything on there, i have checked fuse connection but nothing is making the boiler switch back on..Any ideas please?On 2017-02-21 by (mod) re: oil burner won't start, no red lights, pushing the reset doesn't work
TonyOn 2017-02-21 by Tony
My boiler does not start. No red lockout light, when I push lockout button fan runs for a short time then shuts down. The fuel system appears to be functioning correctly and I have already changed the Control box.........Any Ideas?On 2017-02-18 by (mod) re: oil burner keeps going off on RESET
John
Watch out: When an oil burner keeps going off on reset DO NOT keep pressing the reset button. The risk is that un-burned oil accumulates in the combustion chamber and then is ignited to cause a puffback explosion.
Search InspectApedia.com for PUFFBACKS, OIL BURNER to read more about that worry.
If going through our checklist doesn't find an obvious problem it's time to call a trained service technician.
Often the obvious problem is a dirty nozzle or oil burner nozzle electrodes, but there may be an underlying issue that causes those problems, like dirty oil, missing filter, water contamination, air leaks in oil lines, even a loose electrical connection or a dirty cad cell eye.
On 2017-02-18 by john
run for about 10 to 60 seconds then shuts down ,oil furnace, beckett burnerOn 2017-01-28 by Emily
@Ruko,On 2017-01-27 by Ruko
high winds go down the chimney and shuts off oil fired heater.On 2017-01-27 by (mod) re: oil burner won't fire
Anon,
When your furnace will not fire, my best advice, since I have no other information about your system, is passed through the checklist of diagnostic suggestions in OIL BURNER WONT RUN.
I start by making sure there's power to the heater and that there is fuel and then I watch what happens when I try to start the system.
On 2017-01-27 by (mod)
Emily,On 2017-01-27 16:32:05.618266 by Anonymous
My furnace will not fireOn 2017-01-27 by Emily Thompson
I have a Honeywell oil furnace ignition box, the light is a steady red light. I change the thermostat, the electrodes, eye, nozzle. Yes I am getting Voltage. Do I need a new ignition box?On 2017-01-24 by Ruko
high winds go down the chimney and shut oil fired furnace off.On 2017-01-23 by Timothy jackson
Will not igniteOn 2017-01-13 by (mod) re: no fuel comes out of the oil burner nozzle
Sounds like a clogged nozzle tube, nozzle adapter, or nozzle.On 2017-01-12 by Maurice picard
Fuel up to side of burner none at nozzle brand new burner and nozzle...
Continue reading at OIL BURNER WONT RUN - topic home, or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.
Or see OIL BURNER WON'T RUN FAQs-3 - more recent questions and and answers about oil burners that misbehave
If the oil burner starts but does not run properly see these diagnostic articles
AUDELS OIL BURNER GUIDE, INSTALLING, SERVICING, REPAIRING - an online PDF of a complete oil heat service text book (albeit an old one)
OIL BURNER WON'T RUN FAQs-2 at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.
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