Help for oil smell

Jaybee097

I have an 880 sq ft home, one floor, dirt crawl space underneath.  Heated by forced hot air via Navien hot water heater and supplied by propane. My question, ever since we moved in, every once in a while (esp on damp cooler days when heat is kicking on also rainy days in summer) we get what I can describe as a faint heating oil smell only in the front part of the house.  To my knowledge, this house has always been supplied by propane, never oil but it’s an old house so it’s possible at one point it was supplied with oil although that never came up when I bought it 8 years ago.  So where the heck is the smell coming from? Neighbors use oil to heat their homes and are close by but no oil smell outside. 

Thanks in advance! 

Big Ed_4

Check the dirt crawl space ..

Jaybee097

Yes, we’ve actually had a few contractors under there this year looking to seal it and no mention of stronger oil smell or remnants of prev oil tank just a very musty odor. 

Jamie Hall

As @Big Ed_4 said -- check the crawl space. It may very well have been heated with oil at one point -- 8 years is not so long ago.

delcrossv

Damp cold days/rainy days leads me to believe there's some contamination below the surface in the crawlspace that's brought up when moisture enters the soil. Oil floats on water.

Jaybee097

A.) should i be worried?
B.) how can I find out if there ever was an oil tank? 

I have looked already for obvious signs of one and have not found anything….yet….but the smell is an indicator! Just worried if there’s an old leaky tank! House was built in 1932 

Jamie Hall

1932?! There was an oil tank. The questions are: where was it? Was it removed? Had it leaked? And if it had, was it remediated?

It is possible that you may be able to find the answers -- or at least one or two of them -- in the records of the building inspection or fire marshal offices in your community. That depends a good deal on how conscientious those offices were -- which varies widely -- and whether or not the removal or discontinuance of the tank was done with any permits -- and we all know that homeowners (and fuel companies) sometimes get very creative.

In terms of immediate hazard, if you don't have an on-site water well or a basement there really isn't one. However... now that you are aware that there is or may be a problem, if you were to sell the property you would have to disclose that, and it would have to be investigated. If it turned out there was indeed contamination of the soil -- or worse, a buried tank of unknown condition -- it would have to be remediated. It is possible that your homeowner's insurance might cover that, or at least part of it.

MaxMercy

Agree with Jamie - almost certainly heated with oil at some point in the past if you're in an area with most homes using oil heat. Probably an abandoned oil tank would be my guess.

In the meantime, have the heating ducts been sealed? Even if they're only insulated, they should be sealed before insulation to prevent picking up outside air.

EDIT: You said your neighbors use oil, if the houses are close together, you may be getting that smell from a neighbor's leaking tank. You probably wouldn't pick up the smell outside because of air movement. The only way to tell would be to do core samples.

Jaybee097

No heating ducts that I have seen, but what might they look like? we currently have baseboard hot water heat supplied by a Navien unit.  I suspect it was baseboard prev too

retiredguy

If you have any neighbors that heat with fuel oil, you could be getting that smell from their units since on cool rainy days when the atmosphere is heavy, and flue gases tend to fall and there could even be down drafts forcing the flue gases towards the ground. Depending on the direction of the prevailing winds you could have smells in front of your home and not theirs. I was once at a school building and during certain days, even bright sunny days flue gases would fall from the roof above the 3rd floor be picked up by the wind currents and drop down to a corner of the building's first floor and be sucked into a couple class rooms by the heating univents. I determined this by using a smoke generator using colored smoke.The "fix" was expensive.

ChrisJ

Jaybee097 said:

No heating ducts that I have seen, but what might they look like? we currently have baseboard hot water heat supplied by a Navien unit.  I suspect it was baseboard prev too

You typed forced hot air, I think it threw a lot of people including my self off.
I'm guessing you actually tried to type forced hot water.

That's an interesting spell correction, the AI is even pushing hot air........