Chimney flue relining or another option - Oil Furnace Expert Needed
i have an oil furnace. Last year when the heat came on, the house started smelling of fuel from the vents. I had my oil company come over who does maintenance and when they opened the furnace up, it was covered in oil. They cleaned it up and said that the smell was coming from a dirty furnace. The smell was still there after they cleaned it when it ran again. I called them back again and they did the same thing and it was still there. I went to a new guy who teaches furnace work and heating for the state of maryland. He took it apart, found the inside was filled with oil, replaced a part, the igniter maybe, and ran the furnace with the probe to test and get specs. I think he said that it wasn't getting enough oxygen and that was the cause of the my problem. My furnace is vented through the chimney flue so I got a chimney company to come out and clean it, to see if that would fix the problem. It didn't, so I was told after the chimney inspections that the inside of my chimney was breaking down and that I needed to get it relined and that would fix my problem. My house was built in 42 and the flue is lined with terra cotta tiles which are falling apart.
I got 3 estimates from chimney repair companies. one wanted $3000, one wanted $2500, these were to install a new liner and vent it through that. A third one wanted $5000 to take out all of the tiles and then rebuild it. All of these prices are a lot for me. Do they seem reasonable?
But here's my big question:
How can I be certain that this is the problem and not the furnace itself, my biggest fear is that I get the chimney flew relined and the problem still exists.
These are the numbers the probe came up with:
511.5 °F T stack
57.3 °F ambient temp
48.9 °F instr temp
3.1 % oxygen
13.38 % CO2
-.036 in H20 Draft (this is the problem?)
16.2 % ExAir
0 ppm CO
- ppm aCo
0 ppm Untiluted CO
- °F T1 temp
- °F T2 temp
Do these numbers confirm that the chimney flue breaking down is causing the problem and if I get it relined it will end the problem of oil smell coming out of my vents?
Also, I talked to a neighbor and he said he hired the main energy company here to put in a new gas furnace and they just punched a hold in his basement wall and vented it there. Is this an option for me?
I was thinking of getting an electric furnace to avoid this repair but I'd have to get a new water heater too because it is gas and vents through the flue as well. The tech who came by said that my furnace has at least 10 more years in it and if I switched to electric it would cost way more money to operate and not be worth it.
First off, my disclaimer. I have not worked on oil fired furnaces for at least 25 years.
Are you smelling the oil thru the vents or the burned exhaust? My suspicion is it is the oil that has saturated the refractory material inside the burner box. This can be a problem with poorly maintained oil systems. They really should be inspected, cleaned and tuned at least ever 2 years. Over time it may burn off most of it from the inside. If any leaked outside of it then it will have to be taken apart and cleaned or replaced. You mention you have gas. If you are going to change over from oil why not go with a gas unit. Most all new gas units now can be vented thru the sidewall as well as some water heaters.
How can I tell the difference between smells?
I got tired of smelling the oil and feared that I was sitting in my house inhaling poisonous fumes every time the heat came on! I haven't turned it on since last winter and it's getting cold in my house...
The guy who seemed to know what he was talking about took the whole unit apart and cleaned it and replaced what needed to be replaced.
At this point I would like to spend as little as possible because I hope to move in the next year but still want to do it correctly.
If relining the chimney flue is least expensive I will do that, but if it is cheaper to get a new gas furnace, I will do that.
Can I get a new gas furnace purchased and installed by a reputable person for around $2500?
I would still like to know about the numbers from somebody who can read this printout.
OK a few things here that need to be determined:
The odor you are getting. Is it a raw, unburned fuel oil smell or is it exhaust? The easiest way to describe it would be does it smell like a diesel truck running in your house or is it really pungent and smells like raw fuel?
If it is raw, unburned fuel then you have incomplete combustion happening and frankly no amount of cleaning anything is going to take care of that problem. Your fuel handling parts ie. the fuel pump strainer, the filter, the nozzle and the oil line must be free and clear of sediment and that the fuel flow is consistent. You must make certain that you have a good, strong spark coming from your burner ignition transformer. You must be certain that the burner end-cone is free of slag and dust and all the openings on it are clean. You must make certain that the air handling parts like your burner fan cage is clear of accumulated dust. Your air intake openings need to be dust free so you are getting the full air supply to support clean combustion. Your pump pressures need to be checked to insure that you are not overfiring or underfiring the unit and the design BTU input of your unit. Your combustion chamber must be clear of any debris on the inside so you are not getting flame impingement when your burner is running. You must make certain that the pump coupling is tight and not lose and slipping. In short, changing parts except for the fuel handling ones are not going to address these problems.
If the odor you are getting is the products of combustion, then there are a few things that need to be checked. Since you said it is coming from the vents then I am going to guess that the unit is a warm air furnace and not a hot water boiler. First, the unit must be thoroughly inspected for a cracked heat exchanger. If the integrity of the heat exchanger is compromised then you have no alternative but to replace the entire unit unless it is under warranty and then you still have to replace it, but your cost may be pro-rated depending on what company manufactured the unit. A few other causes may have the products of combustion being pulled into the living space. By any chance have you done any replacing of windows, insulating, sealing up air leak cracks with foam insulation, used a "house wrap", put up new siding, or any other home improvements that may make the living space tight enough to prevent combustion air from entering the home? If you have, then there are some solutions for that, but I need an answer to the question before I proceed. The other question is do you have return air ducts running to the upstairs or is this an open return in the basement meaning no ductwork? Please provide as many pictures of the furnace area that you can. This will help us "see" the system and see potential problems.
Frankly the numbers you gave us will not help in determining much as far as troubleshooting. The reason for that is those numbers will only give us the conditions of the unit while running during a very short period of time. Right off the top I do not see anything that is indicative of a problem. The number that you thought may be the problem (the over fire draft) is acceptable. If it was in the positive then you would have a problem.
The one problem that could be totally unrelated is your chimney being oversized for the efficiency of the unit. If they have determined that the terracotta liner is deteriorating, and I would want proof of that or to be shown that, then you may need a stainless steel chimney liner. High efficiency units may cause condensation within a chimney that is too large to support the small amount of heat being produced and you can actually condense the moisture in the combustion gasses on the chimney walls. That condensation can soak into the terracotta liner and freeze and break apart the chimney. Replacing the terracotta is not an option because that will not solve the problem. Lining the chimney with a properly sized liner will create a situation where the liner heats up quickly, and cools down quickly which will minimize any condensation. While draft problems can cause odors, I do not believe that the amount of odor you are getting is a result of the chimney problem... it could contribute, but units that suffer from deteriorating chimneys can run fine without odors unless the chimney gets blocked somehow or there is a terrible downdraft problem.
The bottom line is there is no fast and easy answer here. You need a good reputable company to come in there and look over the system. And not to knock anyone, but until someone spends a lot of time in your home, checks everything that I have outlined here and really gone over and above merely changing a part, then you are not getting the service that you need.
For your other questions about cost. I cannot tell you what things cost because thing vary so much, but to line the chimney, about $2000 to $3500 sound about right. Of course make sure they are licensed (if required) and insured and get a full and complete description of the work to be done in a quote before you sign anything. Ask questions about their warranty work, and ask for references. Check the Better Business Bureau website and sites like Angies List and Yelp for their reputation.
As far as replacing your oil unit with a gas unit, yes, you can do that of course, but it is going to be a lot more expensive than the $2500 you asked about. If you are content to stick with oil, then do so and fix the problems you are having. If you do not want to stick with oil then convert to gas, and high efficiency gas units can easily be vented through the side of the home.
As far as maintaining what you have, you should clean oil units once a year. Gas units are not as critical as far as that goes, so every two years for gas is OK... but you still may want to get it cleaned and maintained once a year. You will never, ever hear me argue against preventative maintenance.
You have your work cut out for you. Get us a lot of pictures. Pictures of the unit, the burner, the chimney base where the flue pipe enters the chimney, and the ductwork directly around the unit. The pictures may help us... they normally do.
Sorry for the wall of text... but you have a lot of things to look at and I just could not address them in a few lines.
Please get back to us and we will keep assisting you as we can.
FCLef, thanks for taking the time to write all of this for me! I'm going to spend the next few days getting the pictures together.
Your gas water heater being vented to the chimney very well may be what caused the damage to it.
The water heater also is keeping your draft low on the oil furnace. The draft may, or may not improve with a liner.
The high cost for lining your chimney is that it needs to be stainless steel to vent both the oil fired furnace and gas fired water heater into it.
The combustion readings however do not indicate that the chimney is definitely causing your oil odor problem, nor do they indicate it is not. The furnace needs to have it's heat exchanger checked if it has failed/burnt through.
The chimney draft before the oil furnace and gas water heater tie into it, should have been checked.
Ok, I got some pictures together:
If I've left any pictures out or you need any more or any are unclear, please let me know!
I turned the furnace on for the first time and the oder I'm getting out of the vents is unburned fuel - kind of sweet smelling. When I'm near the unit in the basement, it definitely has a strong diesel truck in my house running smell. That can't be good either, can it?
A few extra things I remember:
I will admit, I did neglect to get the unit serviced for maybe 3 years. When the guy came by and opened the lid, like I have in the pictures (#23), it was filled up with oil. He cleaned it out and a few parts he wiped down pretty well. He replaced the nozzle which he told me was an incorrect size and then the new one he put in immediately burnt out and black smoke went everywhere. He took it off and put a second new one on and that has been on and running since.
If I remember correctly maybe once or twice a year in the previous years the unburned fuel smell would come out of the vents for maybe 10 minutes but then go away. It is only in this past year that once it started, it hasn't stopped.
As far as insulation goes, I did add a lot in my roof but it was at the beginning of the year previous to the year that this problem started. I also did add a chimney cap the same year because one of the storms blew the old one off…
One thing that I want to note is that when I did have one of the chimney cleaning companies come over and they pulled the pipe out of the wall, there was maybe a spider web hanging around and one of the guys noted that you could see the draft blowing the web. I don't know how accurate this is but he only mentioned it to me after his boss went out to the truck. It seemed that he didn't think I needed the work done and only waited till his boss left to tell me.
My problem is finding a reputable person to work on the unit. How can i determine they are good without them coming to the house and charging me the $80 diagnostic fee and then not fixing the problem? The next person will be the 4th person to try! I haven't been able to get any recommendations from any friends.
Can anybody recommend somebody in Maryland?
Ok, I appreciate all the help!
They couldn't fix it, they cleaned it and said the smell will eventually go away.
Cost me $80
If you already have natural gas for the water heater then get a gas furnace. Screw the chimney. Maybe its different where you are at but around here fuel oil is the absolute worst and most expensive option for heating a home.
BUmp for the experts
The jacket probably needs to be taken off, and the oil laying around the heat exchanger cleaned up. Time consuming job.
If it was unburned fuel laying in the unit then there has got to be a reason why it was there in the first place. There was either an ignition problem and someone hit the reset button a couple dozen times, or there was incomplete combustion going on, but that would have been accompanied by soot and possible rumbling when the burner was on.
The pictures you provided of the burner itself may tell your story a little better. Under normal conditions, meaning everything is ideal and functioning properly, you should not have a scorched look to the inside of the burner. It also looks like there is fuel oil soaked into the ignition transformer gasket. In my experience, when you see that sort of thing, it screams "draft problem" which could be caused by a lot of things. I'll get back to the draft problems in a second.
When the tech replaced the nozzle and it "burned out" right away, unless the nozzle was faulty to begin with, this should not have happened. Incomplete combustion could also be the result of a dirty fuel handling system. Your oil filter, your pump strainer and your oil line should be free of dirt and sludge. Ideally, the pump strainer and the oil filter should be changed annually. If you have a dirty fuel handling system, that could be why the new nozzle plugged right up and caused a problem... but it doesn't mean it is the problem, it just could be.
The draft problems could be caused by lots of things. And believe this or not, it could be a result of your insulation settling and cutting off supply air to your burner. I have seen things like this where the heating appliance can actually draw the house into a vacuum because it is taking air from inside the home and there is not enough air infiltration into the home to make up for what is being taken out. There is an easy way to diagnose this problem. You have windows in your basement... what you do is you leave one open about an inch for a day or two and let the heater run as normal. See if the smell goes away. If it goes away and everything is running well, you now know that you must bring makeup air into the home. Try this first to see if this may be the problem and we can give you ideas how to fix it if it is indeed the problem. It may not be, but it is certainly worth a try to at least eliminate one possible cause.
Testing out the open window idea, will be back with results soon
Ok, I think I've gotten to the bottom of what is going on. I'm glad I went with my gut and was skeptical about the chimney relining solution.
The repair guy ran his hand underneath the burner and found that it was wet with oil, he said that it has a blown pump seal. Does this sound like the culprit?
Secondly he removed the caps off of the 2 holes and found that it was insanely filthy!
Here's a pic -
This is crazy, right? He said it could have started a fire! Why is it that I had 3 repair guys here previous to him and none of them opened this part up? In the past 7 years I've lived here, I've had the unit serviced every year except for the last three. There is no way that this could be from only 3 years of accumulation, is there? Is checking this not standard maintenance?
So ok, now I would like some advice - For $325, they said they would replace the leaking pump, clean out all that soot and put on a new nozzle. What are the chances that after they do this the unit will still blow out the smell of oil?
The unit is 20+ years old, after seeing all of this should I just get a new gas furnace? I'm going to sell my house in the next 6 months, so I don't want to invest this kind of money if I don't have to, but could a new gas furnace in place of an older oil furnace raise the value of my house and potentially help me sell it as opposed to a oil unit turning people away?
|All times are GMT -5. The time now is 12:32 AM.|