Noticing what's going on, even something as simple as a utility room door that is shut to cut off combustion air, can make a big difference in diagnosing oil burner malfunctions.

This article series explains how to inspect, diagnose & repair oil burners used on oil-fired heating boilers or furnaces using a visual inspection approach as well as (optional) simple test equipment.

We include a description of common oil burner adjustment and operating problems and we illustrate some of the basic oil burner tests and measurements made in servicing and adjusting the equipment for safe, efficient operation. The articles at this website describe h

ow to recognize common oil-fired heating appliance operating or safety defect.

Boiler or Furnace Room Clues May Explain Oil Burner Trouble

An expert inspection of an oil burner begins either with having made note of building owner/occupant concerns (noises, odors, no heat, high fuel costs), or with having made some basic visual observations outside: a sooty chimney top, for example.

The page top photo shows signs of water running down the chimney and through the flue vent connector - a possible cause of damage to the heating equipment.

The chimney itself may just need a rain cap, or the chimney may actually be unsafe, having been damaged by water, spalling, rust, or frost.

In our photo of the oil burner at above/left we see lots of soot, debris and crud around the unit - and a rusty lally column.

We also see what looks like water stains below the round combustion chamber inspection port to the upper left of the oil burner.

This heating equipment needs a much closer inspection for condition and for safety; I suspect there's water damage.

The oil burner inspection continues indoors, even before entering the utility room where the oil burner (or often more than one of them if oil fuel is used for both heating and a separate water heater) is located: look at the building interior as you enter:

are there odors, soot deposits, noises associated with the heating system?

The oil burner inspection becomes detailed, and diagnostic, when you can actually see the equipment.

It's obvious that you should notice oil leaks, soot in the boiler or furnace room, noises, odors, signs of repeated repairs, piles of junked parts, signs of unprofessional work (covers off of controls, sloppy wiring or plumbing).

But just what each of these clues might mean bears some additional explanation that we offer below.

• First, Identify the heating system components 
  
  in each building area.
  
  How old is the equipment, what are the signs that parts have been replaced (new transformer, new valves, new oil piping, new filters, new fuel units, discarded parts nearby).

• Oil burner controls may themselves be a source of trouble -
  
  See CAD CELL RELAY SWITCH
  
  and STACK RELAY SWITCH and also
  
  see AQUASTAT CONTROL Functions
  
  and THERMOSTATS.
  
  For oil fired warm air systems (furnaces) also
  
  see FAN LIMIT SWITCH control on heating furnaces.
  
  Controls for oil fired steam heating systems are discussed
  
  at STEAM HEATING SYSTEMS.

• Look for damage to the furnace or boiler itself:
  
  if the boiler or furnace is old, cracked, rusted-through, leaking, damaged, repairing the oil burner may be the least of the owner's risks.
  
  And if the boiler, furnace, or water heater is unsafe or needs immediate repair or replacement, fixing the oil burner and leaving the job is dangerous.
  
  Our photo above shows a rusted-out furnace that should not be used, and needs immediate replacement. Fixing its oil burner, or even inspecting it would be foolish
  
  Watch out: if it is in use, this furnace should be left shut down, red-tagged, and appropriate oral and written warnings issued.
  
  If the furnace, boiler, or water heater has had a safety recall, that's critical information for the owners to know about.
  
  For example,
  see BLUERAY HEATING BOILERS & FURNACES SAFETY RECALLby the US CPSC, with additional history, photos, and technical details.
• Look at the heating equipment's service tag: 
  
  has the equipment been serviced annually; are there records of other no-heat service calls
  
  - often a good service tech will note on the service tag the no-heat call, the diagnosis, and what parts were replaced.
  
  At HEATING COST REDUCTION ADVICE: How to Save on Home Heating Costs, we discuss heating tuneup tips for oil burners to reduce heating cost.

• Oil fired equipment efficiency measurements:
  
  If you do not see a small (roughly 1/4" diameter) hole in the flue vent connector just above the boiler, before the barometric damper, then this heating equipment has never been properly tuned and measured for proper operation.

While it was possible to "eyeball" older oil fired equipment (spit on the flue for temperature and blow cigarette smoke at the burner for draft), modern oil fired equipment requires more accurate measurement and adjustment for good operation.

As our sketch above from the AUDEL OIL BURNER GUIDE (free online book) shows, measuring the stack temperature and CO₂ level gives a critical indication of the heating system efficiency, in other words, measuring what percent of each dollar spent on heating oil is going up the chimney versus into the building as heat.

The Guide also includes this CHART of OIL FIRED HEATING SYSTEM EFFICIENCY [image] at different CO₂ levels and stack temperatures.

The little hole we describe is where the service tech inserts test equipment to measure stack temperature, smoke level, and CO level. Some tech's use two holes to permit more than one measurement simultaneously.

No hole in the flue vent connector means that this heating system has never measured. (Or new flue vent connector parts have just been installed on older equipment and no one has made a hole yet.)

Details about this procedure for measuring oil burner efficiency are

at OIL BURNER CO₂ TEST.

Our photo (left) shows a Bachrach stack temperature measurement being made "in the breech" above a troublesome oil burner and boiler installation.

Watch out: don't record the stack temperature before the oil-fired heating system has been running for five minutes or so - you want to be sure the system has reached its stable and "normal" operating temperature.

Waiting a few minutes at this boiler we saw the flue temperature rise to 600 °F [photo]

At 600 °F. this heating system was left running a bit "hot" by the service tech.

Why? Because a too-short chimney meant the system had a history of inadequate draft, sooting, backpressure, puffbacks, and loss of heat.

This "fix" was a band-aid that kept the system running longer between (frequent) service calls, but at the expense of higher heating bills and wasted fuel.

We could have addressed this short chimney with a draft inducer fan, but a taller flue would be smart anyway, to get the chimney top higher than the roof surface. We discuss examples of extending chimney height to improve draft, performance, and fire safety separately

at CHIMNEY HEIGHT EXTENSIONS. We discuss draft inducer or "draft boosting" fans for heating systems (and maybe for some fireplaces)

in detail at DRAFT INDUCER FANS.

Just how short is "too short" for a chimney is a problem along with roof clearance requirements discussed

at CHIMNEY HEIGHT & CLEARANCE

• At the heating boiler or furnace,
  
  identify the fuel source and follow fuel supply piping to its source (an oil tank, LP gas tank, or gas meter, for example) - you may spot the oil leaks and piping problems we mentioned above.
• Look at the oil burner combustion air supply -
  
  it's remarkable how often the oil burner service tech tunes up the system with the door to the boiler or furnace room open (who wants to work in a little closet), then leaves, closing the door, and shutting off the only combustion air supply to the equipment - a likely cause of sooty operation and other troubles.
  
  See COMBUSTION AIR DEFECTS.

• Look at the furnace or boiler connection to the chimney -
  
  the flue vent connector, barometric damper, and for signs of trouble with the chimney itself (no cleanout door, air leaks, blocked flue).
  
  See CHIMNEY INSPECTION DIAGNOSIS REPAIR for the chimney itself, and
  
  see FLUE VENT CONNECTORS, HEATING EQUIPMENT for a discussion of flue vent connectors, signs of blocked flues, dead end chimney hazards, and other venting defects that can cause oil burner operating problems.
• Look at and look into the barometric damper or draft regulator:
  
  is there one installed, is it properly installed, is the flue thick with soot, is soot blowing out of the draft regulator?
  
  Our photo above hows so much debris in the breech of this oil fired heater that the oil burner is likely to see trouble itself.
  
  See DRAFT REGULATOR, DAMPER, BOOSTER for details.
  
  A discussion of this particular photo and those rusty sooty fragments in view is found
  
  at HOW TO INSPECT a BAROMETRIC DAMPER or draft regulator

Readers needing an approach to heating system inspections that assures thoroughness, should also

see HEATING SYSTEM INSPECTION PROCEDURE where we explain an organized approach to inspecting the entire heating system, beginning outdoors, continuing indoors, and ultimately in most detail in the boiler or furnace room.

To find what you need quickly, if you don't want to scroll through this index you are welcome to use the page top or bottom SEARCH BOX to search InspectApedia for specific articles and information.

...

...

Continue reading at OIL BURNER VISUAL INSPECTION or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see these

Recommended Articles

• OIL BURNER INSPECTION
• BUILDING EXTERIOR Oil Burner Trouble
• BUILDING INTERIOR Oil Burner Trouble
• OIL TANK EFFECTS on OIL BURNER
• BOILER / FURNACE ROOM TROUBLE SIGNS
• OIL BURNER VISUAL INSPECTION
• OIL BURNER OPERATING TROUBLE
• OIL BURNER INSIDE TROUBLE
• OIL BURNER CO₂ TEST
• OIL BURNER SMOKE TEST
• OIL BURNER WONT RUN - Diagnostic Steps - what to check in what order
• HEAT WON'T TURN ON

Suggested citation for this web page

BOILER / FURNACE ROOM TROUBLE SIGNS 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.

---

 

IF above you see "Comment Form is loading comments..." then COMMENT BOX - countable.ca / bawkbox.com IS NOT WORKING.

In any case you are welcome to send an email directly to us at InspectApedia.com at editor@inspectApedia.com

We'll reply to you directly. Please help us help you by noting, in your email, the URL of the InspectApedia page where you wanted to comment.

Citations & References

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

---

ADVERTISEMENT

---