Diagnostic questions and answers help figure out why you hear rattles or clanks at the oil burner or at your boiler, furnace, or water heater.
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.
InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.
- Daniel Friedman, Publisher/Editor/Author - See WHO ARE WE?
(Sept 11, 2019) jim powers said:
Hello, and thank you in advance for the help. I have an oil fired hot water tank. / / forced hot air. Whenever it goes on i hear a banging popping / clanking sound almost like a flap opening and closing.
This ONLY happens when the hot water tank goes on and stops when it goes off. You can ONLY hear this banging noise in my living room near the chimney / fireplace.
You can’t hear the noise while standing in front of the water heater while it’s on. I've had 2 service guys come out and inspect my hot water tank.
They say it’s good and has good draft. One service guy heard the banging noise while standing in my living room near the chimney / fireplace and did not know what it was.
I have the fireplace flew closed as we don’t use the fireplace. I climbed up on the roof, looked down both sides of the chimney and no animals, nests, or obstructions were present. I checked the hot water pipe from the tank and it was not lose or rattling.
Both pipes from the tank go away from the chimney and wall where the noise comes from. I do not have a chimney cap, but it’s been like that for 20 years with no problems.
One side of the chimney at the very top has a space between the bricks and clay. I don’t know if this has anything to do with it. ANY HELP WOULD BE APPRECIATED. THANK YOU!
Jim
Check the barometric damper (draft regulator) flapper door - watch it during an oil burner start-up or shut-down cycle and see if the door is banging and flapping.
Watch out: if nobody has touched the damper and it's not damaged, the noise COULD be due to an improper ignition such as igniting an accumulation of previously-un-burned heating oil that was left at the end of the previous burner-on cycle.
That happens if the oil burner is dirty or out of adjustment.
Watch out: also because you say the noise only occurs when the water heater burner starts. That points to a problem with the oil burner on that appliance.
Look in the ARTICLE INDEX for and read about PUFFBACK EXPLOSIONS to be sure we're not facing that hazard.
(Sept 11, 2019) Jim said:
Thank you, i appreciate the help. I did have 2 oil burner techs come out (at different times) and the flapper door on the exhaust flaps freely by hand, and does not flap when the oil water heater goes on.
This flap / door is located on the exhaust pipe of the oil burner heater (forced hhot air) and water tank.
They share it. Both techs said it was working properly. IS THIS THE FLAPPER DOOR YOU ARE TALKING ABOUT? Thank you much appreciate the help.
Yes that's the damper I'm talking about.
By the way a SHARED barometric damper that has to handle the "exhaust" from two different heating appliances CANNOT ever work properly. Each heater or each oil burner needs its own barometric damper.
Just figure that if the tech adjusts the damper for Appliance No. 1 to give that burner the proper draft, when Appliance No. 2 runs all of the conditions are different and when both No 1 and No 2 are running at the same time, all of the conditions are different again.
So noy possible setting at the damper will work to give the best oil burner operation for all three situations:
That's presuming I understand you correctly and there are two oil fired heaters in your home: one for heat and one to provide domestic hot water.
Details are at SHARED CHIMNEY & FLUE HAZARDS
Also just listen for a bang or puff or boom when either oil burner starts. If you hear that - at the burner - then the burner is not working properly and it is unsafe.
Obviously NOBODY with any sense will pretend to diagnose an oil burner by a brief e-text so I've no recourse but to warn you about what could be the case = I do not KNOW what's happening in your home. Your onsite service techs have to address these questions.
OIL BURNER SOOT & PUFFBACKS has more information about banging noises at burners
(Sept 11, 2019) Jim said:
Ok, i will read that again. Thanks for the explaination.
I will ask the oil burner tech who cleans my oil burner and hot water burner about the damper you are talking about. again thank you for the quick response.!
Also, it is making a LOUD clanking noise--did prior to delivery but not as often--what is this?
I just got a (3.57 a gallon!) first oil delivery of 100 gallons at the house I am renting. I only went through 3/8+/- of a tank from May til last week (I live on Cape Cod, MA--just getting into the 40s here--the oil was only used to heat hot water until a few weeks ago--now daily for heat and hot water);
[Click to enlarge any image]
Sketch at left provided courtesy of Carson Dunlop Associates, a Toronto home inspection, education & report writing tool company [ carsondunlop.com ].
I wanted to wait until the tank was at @1/8 full-bad idea. (I am a disabled single mom w a 9 year old) I thought I was ok to wait for my next SSDI check on 12/3 but "ran out" of oil on 11/24. I finally got some $ to get 100 gallons.
My evil bad-tempered landlord (think the Grinch without good qualities said if the tank was "broken", I would be held financially responsible. She never said what level to fill at--I had paid her $300 at move-in for 1/2 tank)
A heating tech purged the line and got the furnace started but shutoff again (pre-delivery - backtracking for context). I took my son to my Mother's house for 3 nights to stay warm/didn't ask/tell her to pay for a hotel)
My landlord threatened that I would be held negligent if there was a problem with the tank. She wanted me to pay the tech--I said NO cuz the gauge said over 1/8. She knew I was waiting til 12/4 and had never had oil before for heat. I paid to have the oil delivery company purge/ bleed the line again if needed (with the new oil). It did NOT need to be purged.
The gauge is obviously not reliable--my landlord claims the tank was cleaned and gauge is accurate, BUT if I added 100 gallons to a 275 gallon tank, and the tank gauge is now over 1/2, math tells me that there must be over 40 gallons of sludge/unusable oil!?
(I paid $300 in May for the half tank that was left by previous tenant or after landlord used 1/2 tank -- hard to get the answer from the Grinch; if the gauge said 1/8 left for the sake of this theory--and I added 100 gallons and got over 1/2 tank, and half tank is 137.5 gal, then at least 37.5 gal is not usable!) right?
Thank - Amy Lynne 11/30/12
Amy Lynne,
If the oil tank is not kept sufficiently full, indeed air or sludge drawn into the oil lines can clog the filter or leave the oil burner air-bound - risking loss of heat, frozen pipes, expensive building damages - events worse than just the cost of hiring the service company to bleed air out of the system and keep the system running.
If you think that the oil heat usage rate is abnormal you can check that view by asking the oil company about the home's oil consumption in the past.
And yes, oil gauges are not precise - and can't be given the shape of the oil tank, unless special electronic and calibrated devices are installed - not a usual practice.
And yes, for oil tanks whose oil lines are taken off of the top of the tank, the bottom fraction of oil in the tank is not usable - the oil pick-up line does not extend all the way to the tank bottom as the tech wants to avoid picking up oil sludge or water - also leading to heat loss.
But you're not being robbed - if the oil couldn't be take out of the tank before your tenancy it was there at the start of our lease. You were not robbed. Search InspectApedia for OIL TANK GAUGES to read details.
Loud clanking noise or any other odd noise from the oil burner merit prompt attention from the service company as you risk not only loss of heat but a puffback or other unsafe conditions.
You should check your lease terms with an attorney but most often the tenant is indeed responsible for keeping oil in the tank and heat working lest the home be damaged. Don't cut it too close to the wire in ordering an oil tank fill-up.
Hi, we have a 9year old furnace, we had it inspected by an actual heating and cooling company when we moved in 2 years ago..he said the combustion ventilator motor is going(it rattles and hums) quite loud ,,,is it very dangerous to leave it for another year.
it freaks me out, will it explode, and or cause co poisoning
we have co detectors . -katherine
If by combustion ventilator motor you mean a motor that is used to induce a draft for the heater, I would replace it asap. The worry is that the motor may stop entirely and as luck will have it, at 2 AM on a holiday when you'll pay an arm and a leg to get the service tech out for an emergency no heat call.
The motor won't explode but if it stops working, either the heater will also stop working (depending on what safety controls are installed) or worse, it could keep working and produce dangerous CO gases - for which your detectors are a first line of defense but not a solution for safe operation.
5 Jan 2015 Anonymous said:
single pipe steam system in 20 apt walkup in NYC. ground floor rads are pooling water (yes, they are sloped slightly towards pipe to drain properly). We temp. drain the water so the hammering goes away but regularly when system starts up (no water) first 10 min. goes quiet for abt a minute.
then you can hear bubbling sound just before system kicks in again and then loud clanking almost gear shifting sound starts for a few seconds. after abt a minute run stops for abt 30 sec. bubbling sound again, then a popping noise and the boiler kicks in again with more clanking but not as loud. rest of the startups are mostly quiet.
This happens every hr. (there are about 6 start ups and stops within one run). 15 min of quiet btween runs when the weather is really cold. Landlord is not being helpful. any feedback or anything that a super for the bldng can do until the boiler people come would be greatly appreciated.
Anon:
It sounds to me as if there is a blockage in the building's condensate return piping system. If that's so, the problems are more than just noise and clanking, but also excessive boiler water usage, increased rate of boiler and piping corrosion, possible leaks into and damage to the building, and stretching out a bit, a potential for leak-related mold contamination and health issues, depending on what gets wet where when a leak occurs.
I'm doubtful that a building manager can fix a problem like this as the steam heating experts need to find and fix the blockage. What a building manager can do is call the service company and also screen the building for leaks or for areas at risk of freeze damage from loss of heat.
See also OIL BURNER CLANKING RATTLING NOISE
12 Jan 2015 Anonymous said:
thank you for your response. could the blockage(s) be in one of the apt's or just in the basement with the boiler?
Reply:
Anon
A condensate blockage can be anywhere; it's often at individual radiators and very often close to the boiler at the lowest section of condensate return line.
...
Continue reading at OIL BURNER NOISE SMOKE ODORS - topic home, or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.
Or see these
OIL BURNER CLANKING RATTLING NOISE at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.
Or see this
Or use the SEARCH BOX found below to 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.
Search the InspectApedia website
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
In addition to any citations in the article above, a full list is available on request.