Cobwebs in the flue: Do I really need a stainless steel liner for my oil furnace?

[discovery17]

I recently moved to a house that uses oil for heating. A chimney sweep found cobwebs inside the furnace flue. The flue has old clay liner with some "gaps", as I was told. He told me I should install a stainless steel liner "as soon as possible". The cobwebs, he said, indicate that there is bad draft. Therefore, I have problems...

Would an expert on those things confirm that I have problems and have to do the job ASAP. And what kind of problems? Carbon monoxide going back in the boilder room? I have two detectors and so far no signs of CO in the basement (or anywhere in the house).

Essentially, I don't have a budget for the job right now. I would do it if's a bit of an emergency. The house is 50 years old and the furance is about 15 years old (I suspect it's not the "high efficiency one" which does require the stainless steel liner as I understand it).

Thank you.

 

[__dan]

Not being a heat pro or flue guy I am going to guess that the chimney sweeper does not know what your draft is unless he checked it using a pro method, some type of guage or meter.

I will also guess the cobwebs indicate nothing, except maybe no recent use. It it 2019, they have cameras for that. Pulling up cobwebs on a brush probably did not indicate anything in the 1980's either. Unless he has pictures of the gaps or pieces of the old flue came out when he tried to clean it, I don't see how spiders by themselves are going to be a problem.

You may want to try to verify his statements as true or false, probably with the camera but there may be another way. Age of the house and original installation date would be a big clue. Is it 50 years old or 200 years old.

You would not want flue gas condensation in the flue. which is when the liner is usually called for. I would never expect the CO detectors to save me from some actual problem.

If there is actual damage to the flue or suspected damage, spending the money to determine if this is true or not may be advised. You may want a second inspection. Being a new owner of an old house, there are certainly guaranteed problems to be found.

 

[bholler]

You may very well need a liner. But the cobwebs have nothing to do with that. And are not an indicator of a problem.

But being 50 years old those clay liners are about 20 years past their expected life expectancy. So I would not be surprised at all if they needed replaced

 

[discovery17]

Dan and bholler, thank you for you responses. I saw inside the clay liner; it looked like it was full of sand. I went ahead and installed a SS liner to have a peace of mind.

 

[Ashful]

Good move. I suspect the cobwebs were being cited for their lack of movement, as an indicator of poor draft, not that their mere presence was a problem.