Why is the oil burner humming? Is it refusing to start or just making a vibrating noise?

This article series describes the cause and cure for just about any noise that you might hear at or near an oil burner, where it comes from, what it means, and what needs to be done about it.

Diagnose Oil Burner Clicking, Humming Noise or Vibration

Humming Oil Burner Question: oil furnace won't work, the furnace hums but doesn't fire

My oil furnace is not working properly.

The reset button is pressed in and the furnace is humming but not firing. Sometimes when I shut off the power switch and turn it back on it fires but doesn't stay on more for more than 2 mins.

The water pump is hot to the touch but the pipes are cold. I bled the water this morning it was black and there was a lot of air in it but it's still not heating up or even staying on for that matter. What could be the problem? please help. - Tony 2/9/12

[Click to enlarge any image]

Sketch above provided courtesy of Carson Dunlop Associates, a Toronto home inspection, education & report writing tool company [ carsondunlop.com ].

Reply: let's sort out oil burner no-start problems into fuel problems vs. air problems vs. normal operation of the systems

Tony, I'm not sure what "humming" means to you but some possibilities that occur to me include

The oil burner motor runs but you don't get ignition - which can be caused by a number of problems that typically sort out to either a fuel problem (clogged nozzle, clogged oil filter, clogged fuel unit strainer, dirty nozzle, bad fuel unit, airbound fuel lines, or no oil in the tank), or an electrical problem (no power to the burner, a bad primary control, an electric motor that has failed and is stuck)

Circulator pump hot to the touch means that the heater was working previously - enough to heat water in the system.

If you call for heat and the water temperature is within the specified range set by the HI limit on the aquastat, then it's normal for the circulator to run for a while - the burner won't come on until the temperature in the boiler drops about 20F below the HI.

Humming sounds from an oil burner motor that won't start may indicate a seized motor bearing, a coupling failure between the motor and the blower fan, a seized oil burner fuel unit, or a voltage problem.

Details about electric motor troubleshooting are

at ELECTRIC MOTOR NOISE DIAGNOSIS

Humming at the low voltage transformer that powers the thermostat and some other heating controls can indicate a device that is going to fail soon.

See LOW VOLTAGE TRANSFORMER TEST

Huming or clicking at a bad or failing relay in a heating system control device can also be a source of noise

See OIL BURNER CLICKING SOUND

Clicking & Humming Oil Burner Question: Oil burner noise: hums, clicks: Oil burner won't start - just hums and clicks

My home oil boil (Warm-Flow bluebird 50/70) i put oil in and bled the boiler it ran for 1hr and again for 1hr later last night and it seems to have started up as normal this morning for 20min on son and now it wont, it only makes a humming noise like an electric board and clicks off loudly

i hit the red rest button and same thing happens. no fan noise or low grumble as norm.

Please help im so stuck ! - Clark NI

(Apr 16, 2017) Jay said:

My oil burner is making a noise like its pumping all the time and doesn't sound like its getting away right ?

Reply: things to check

Clarke N

When an oil burner won't start in response to the reset button it needs service or repair.

From your description I can't tell if it's a fuel delivery problem or a motor problem. If the electric motor that runs the burner is spinning and the burner makes a fairly loud noise (all parts are moving) but you're not getting ignition the system will indeed keep going off on reset and that may be a dirty nozzle, dirty electrodes, or even a clogged oil filter or out of oil completely.

If the electric motor itself is not spinning, just humming, the motor is binding or the fuel unit is binding and not letting the motor spin.

Check that there is no red reset button popped out on the motor itself - if there is one, when the motor is cool, push it back in and retry. But if that's the trouble I suspect you need a new motor.

Let us know what the service tech finds - it will aid other readers.

Jay

All during the time that the oil burner is running - that is producing flame in the boiler, furnace, or water heater, the fuel unit (oil pump) will run , being driven through a coupling that connects the pump to the electric motor on the opposite side of the oil burner. That's normal. a

If you are hearing a humming or buzzing noise all the time, including when the burner is not operating, then the system should be turned OFF and you want to call for repair.

Details about electric motor troubleshooting are

at ELECTRIC MOTOR NOISE DIAGNOSIS

Also see OIL BURNER HUMMING NOISE

On 2017-11-27 by Anonymous - Becker oil burner that is making a humming sound

I have a Becker oil burner that is making a humming sound when it’s running. The burner fires and stays on and the blower motor is running smoothly. What could this be? Thanks.

On 2018-06-07 by (mod) - common causes of humming at a motor or control

Usually the situation you describe is traced to a bad start run capacitor, bad fan bearings, low voltage, or one of the other causes discussed in the article above on this,pge.

On 2018-06-06 by Steve

I replaced start capacitor but blower fan will still not start by itself, just hums. I was able to start the fan while humming by pushing squirrel cage with screwdriver.

 

Question: humming hot water heat system

(Feb 9, 2012) David Gast said:
I have a hot water heating system in my one story home ( ranch style )

I have purged my system just as you've described doing it here. My problem is a humming noise which develops sometimes in the bedroom which is the greatest distance from the boiler.

The baseboard heaters are hot and there is no indication of air in the system. I have an ample crawl space and have inspected the plumbing and see that the installers used a minimal hole to run the copper tubing through but otherwise I can't see or feel why it should make this humming sound.

I have even replaced the old expansion tank high above the boiler with a bladder type located lower still above but nearer the boiler. I've replaced my circulation pump which is noisy compared to the old one ( same brand Bell and Gossett series 100 ). Have you heard of this problem before? This hum is very annoying 2:00 in the morning.

 

...

Continue reading at HEATING SYSTEM BUZZING NOISE or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see these

Recommended Articles

• AQUASTAT TROUBLESHOOTING
• BUZZING NOISE DIAGNOSIS - in buildings
• BUZZING SOUNDS sounds from A/C, heat pump or inverter or from other equipment in, or, or near buildings
• CAPACITORS for HARD STARTING MOTORS
• ELECTRIC MOTOR NOISE DIAGNOSIS
• FUEL UNIT, HEATING OIL PUMPS
• HEAT WON'T TURN ON
• HEATING SYSTEM BUZZING NOISE
• HEATING SYSTEM NOISE DIAGNOSIS
• HUMMING NOISES in BUILDINGS
• LOW VOLTAGE WIRING SYSTEM COMPONENTS
• LOW VOLTAGE LIGHTING & CONTROL RELAYS
• LOW VOLTAGE TRANSFORMERS, TRANSVERTERS, CONVERTERS
• LOW VOLTAGE TRANSFORMER, TRANSVERTER DIAGNOSIS
• LOW VOLTAGE TRANSFORMER TEST
• OIL BURNER CLICKING SOUND
• OIL BURNER HUMMING NOISE
• OIL BURNER NOISE SMOKE ODORS - home
• OIL BURNER WONT RUN - Diagnostic Steps - what to check in what order
• OIL LINE BUZZ & VIBRATION CURE

Suggested citation for this web page

OIL BURNER HUMMING NOISE at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

Or see this

INDEX to RELATED ARTICLES: ARTICLE INDEX to HEATING OIL, OIL BURNERS, OIL FIRED HEATERS, OIL TANKS

Or use the SEARCH BOX found below to Ask a Question or Search InspectApedia

Ask a Question or Search InspectApedia

Try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.

Note: appearance of your Comment below may be delayed: if your comment contains an image, photograph, web link, or text that looks to the software as if it might be a web link, your posting will appear after it has been approved by a moderator. Apologies for the delay.

Only one image can be added per comment but you can post as many comments, and therefore images, as you like.
You will not receive a notification when a response to your question has been posted.
Please bookmark this page to make it easy for you to check back for our response.
Our Comment Box is provided by Countable Web Productions countable.ca

Citations & References

In addition to any citations in the article above, a full list is available on request.

---

ADVERTISEMENT

---