Watch out: if your oil fired heating equipment can't make it from one annual service call to the next one without blowing soot into the building, sooting up, clogging, and becoming noisy or smoky, something is wrong. If you spot a problem, have your venting system inspected. I stuck my finger in there and came out with a black, powdery mess. But this didn't explain where the soot--and the CO--was coming from. The most common cause of an overheated heat exchanger is as simple as a dirty air filter. 2) Soot can be deposited on the heat exchanger, acting as an insulating barrier. Make sure the professional does a thorough inspection. A year later, I found out I was right. He used a digital manometer to measure the pressure differences between the house and the outside. I'd give your local fire inspector or building department a call to ask their opinion about the use of this device on wood stoves as well as on oil fired heating equipment. Donna showed me her previous two furnace filters. (Caution sealing the house can cause downdrafting problems unless new heating appliances are installed). The attic scuttlehole cover alone was probably leaking enough air to depressurize the house. To rule out other pollutant sources, I asked about lifestyle habits. The soot insulates the heat exchanger causing less heat to pass through the heat exchanger The result will be a buildup of soot around the crack site and/or spots that are a darker color than the rest of the metal. Thats why you need to Click to Show or Hide Citations & References, HOME INSPECTION EDUCATION COURESES (Canada), HOME INSPECTION EDUCATION: HOME STUDY COURSES. Laws aside I personally don't like these devices on oil fired heating equipment. If a gas fired appliance is producing soot, it should be turned off and Immediate service is needed. These conditions should be investigated further by a service technician. A partially or completely blocked exhaust chimney can redirect noxious exhaust odors back into your home. alled where necessary to Excessive soot: Soot is a problem that can occur with gas-fired and oil furnaces. All the same, I have learned that falling in love can be a good thing, in the right time and place. If you suspect a problem with your heat exchanger, have your system inspected immediately. A flue vent connector ((also called the "stack pipe" or "flue pipe") is the metal pipe that connects the oil fired heating appliance to a chimney in order to safely vent combustion gases outdoors. Still, her furnace filters were turning the color of coal. I told Donna to have the water heater and furnace serviced and to give me a call if she had any more problems. Warning: even if the soot layer is thin and fine where you're looking, don't rule out other possible boiler, furnace, flue, or chimney problems. If the secondary or primary heat exchanger is restricted, it can also cause this problem. And she was still getting some soot buildup on her furnace filters. 52-6) What is an indication of too much gas at the burners? Our photo (left) shows soot and crud that has blown out of the boiler flue vent connector and sprinkled itself on every horizontal surface in the boiler room and in a nearby garage. However, if there is a problem with your furnaces venting, you may start to find furnace soot in other places. Fins on the heat exchanger are very close together. This insulation barrier lowers your furnaces efficiency, increasing your energy bills as a result. [We] took [the] furnace apart soot was a good half inch thick on top the nozzle, [though it] was clean the [combustion] chamber where it fires. Just how much soot is ok? When we look in to the flue close to the heating boiler or furnace, such as at the barometric damper shown at above left, it's normal to see a thin coating of soot on the interior of the metal flue pipe. Or use the SEARCH BOX found below to Ask a Question or Search InspectApedia. We didn't put a [draft regulator or barometric] damper on [flue] pipe. Reduce outdoor dirt entry by sealing the house (ie, caulking, weatherstripping, new windows). Today, Donna has a new furnace (courtesy of the manufacturer), clean filters, and no CO in the house air. You need to have an experienced heating service tech help you out with a thorough cleaning of the oil burner and flue, remove the scavenger, install a barometric damper, and inspect the chimney to decide if a more thorough chimney inspection and cleaning are needed. In either case, the it must be taken care of. That leak wasn't surprising: the stack effect was in full force. Using low-grade fuel oil boilers also produces more soot than high-quality fuel. We describe how to inspect, troubleshoot and repair heating and air conditioning systems to inform home owners, buyers, and home inspectors of common heating system defects. BOILER OPERATING PROBLEMS discusses the signs of improper oil fired hot water at operation. Glancing down, I noticed that Donna's 1997 sport utility vehicle had a clean tailpipe, while the tailpipe of Jim's van was caked with black soot. In the six months before they called me, they had started noticing black stains on the walls, ceilings, and carpets. To make a long story short, it was found that the heat exchanger was plugged with soot from overfiring. Over the course of the day and night, this air was entering the house through the faulty door seal, thanks to the pressure difference between house and garage. A hard to access heating system in a cramped nasty area rarely receives thorough cleaning and service. SOOT on OIL FIRED HEATING EQUIPMENT at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice. We have no relationship with advertisers, products, or services discussed at this website. It could be a cracked heat exchanger. I checked the pilots on the dryer and range; both were burning normally and showed no signs of soot. I was in love again, this time with a novel explanation for soot in a home. Filter the air through a ventilation systems, like an air-to-air heat exchanger. So a modest amount of soot accumulation in the boiler, furnace, or flue vent connector is normal between annual service calls. | Back to Contents Page | Home Energy Index | About Home Energy | Once I found those first two problems, along with reasons to rule out the other likely sources of pollution, I was blind to the actual culprit. Our photo at page top shows what was probably several years of accumulated soot, rust flakes, and debris in the flue vent connector of an oil-fired horizontal furnace in a wet moldy crawlspace. Watch out: Safety warning about soot: Sooting can occur with both gas fired and oil fired systems. Soot coming from an oil fired heater warns of improper operation and risks a destructive puffback. It appeared that air was carrying soot into the house. These may or may not indicate a weakening of the steel in the heat exchanger. However, excessive soot buildup can indicate that your furnace is not running at peak efficiency. "Heat reclaimer." If we run oil fired heating equipment too hot, to produce "zero" soot, we're sending too much heat (and money) up the chimney. Apologies for the delay. Opening this damper and looking inside meant we literally "hit pay dirt". Dirty Soot. Firewood thats unseasoned or dried insufficiently contains water. This is a sign that mineral salts are coming through the masonry because too much moisture is inside the chimney. The heat exchanger needs a high volume vacuum cleaning. She said they had each been in service only two weeks. and GAS FIRED WATER HEATERS for safety warnings about soot at heating appliances. Soot layers in boilers or furnaces that are too thick means that the equipment is running "hot" and could even be unsafe. Macmillan Publishing Co., NY, The ABC's of Retention Head Oil Burners, National Association of Oil Heat Service Managers, TM 115, National Old Timers' Association of the Energy Industry, PO Box 168, Mineola, NY 11501. Soot coming from a gas fired heateris probably indicating a very dangerous condition risking carbon monoxide poisoning. He walked outside the house, sampled the rocks by the foundation, looked up into the trees, wiped tissues along the house siding. prevent excessive draft. Build-up or debris can get caught in the burner, disrupting the proper flow of gas. When unseasoned firewood is burned, it creates less heat because most of the fires energy is used to burn away the moisture. Excessive furnace soot causes the heat that the appliance produces to go up into the chimney instead of into the home. Konnerth III, Andrew. That was the case for this system. This gentleman looked like he knew his stuff. By chance, I wandered around behind two vehicles parked in the garage. That made it easier to convince our heating service tech that the system was running "dirty". But over that year, other major problems in the house threw me, and several others working on the case, off the track. The most logical reason would be a cracked or broken heat exchanger (not all that unusual for a newer furnace). Continue readingat OIL BURNER INSPECTION & REPAIR or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX. and there are instruments that can This can range from black soot to white powdery deposits. Some state, provincial, or local codes may preclude the use of these heat miser or heat scavenger devices, either explicitly or implicitly by more general provisions. Zolton Cohen is a building inspector and journalist in Kalamazoo, Michigan. The gas clothes dryer was venting normally. Actions: if the burner is noisy, smelly, sooty, then turn it off and have it serviced promptly. | Home Energy Home Page | Back Issues of Home Energy |. Looking carefully at the jamb of the garage door, I found soot stains on all three hinges. She'd had the rust vacuumed off the water heater burner and had had the leak in the furnace fixed. Could the garage be the source of the CO in the house? Upon startup or boiler shutdown and restartup, cold water circulating in the exchanger causes condensation. Inefficient combustion causes soot to build up on the heat exchanger. Startup flame causes a bit of soot, also if combustion air is dusty all that combines to cause soot/dust/etc to attach to heat exchanger fins. the internal cross section area of the smoke pipe. Find out why you should have your furnace inspected immediately by an HVAC contractor to avoid carbon monoxide poisoning. None of the other dozen or so cracked heat exchangers I've found (out of the probably 400 I've inspected so far on home inspections) contributed even one ppm of CO to the house air. The furnace investigator's manometer confirmed that air from the garage was bleeding into the house. Get regular maintenance. 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