Oil central heating, contaminated oil

[Avocet]

Well, it HAD to happen! Winter approaching, filled the oil tank, and the boiler goes on the blink! Blocked fuel line. I've blown the contents out and there are clouds of black "gunge" in the oil. Running a bucket out of the tank, I get a gush every now and then and a black "blob" comes out with the kerosene. Filter full of black gunge too...

I've heard of "diesel bug" in marine fuel tanks, and I wonder if this is the same thing? Tank is 22 years old and made of plastic.

Is there anything I can do?

 

[Aquaheat]

Well, it HAD to happen! Winter approaching, filled the oil tank, and the boiler goes on the blink! Blocked fuel line. I've blown the contents out and there are clouds of black "gunge" in the oil. Running a bucket out of the tank, I get a gush every now and then and a black "blob" comes out with the kerosene. Filter full of black gunge too...

I've heard of "diesel bug" in marine fuel tanks, and I wonder if this is the same thing? Tank is 22 years old and made of plastic.

Is there anything I can do?

I have seen it once so far in domestic heating tanks but it does happen. Have you dipped with a water finding paste?

The "diesel bug" IIRC is something to do with a reaction between the two surfaces. (oil/water) and something occurs to create a fungicide.

A biocide treatment can be added to kill it but I couldn't tell you what it was called it was years ago!

Draining the water is a good start, then treatment. It doesn't take long to do as it only sits between the two layers.

Sorry I can't be more specific but it has been many years and it is very Un common.

It will be definitely worthwhile checking all your seals and joints on the tank though as to get this you must be getting water ingress from somewhere.

Jon

 

[muggles]

It does sound like diesel bug, which is also an indication of water in the tank, as the bug needs water to survive. You can kill it with a marine diesel bug treatment, but you'll still have the issue of water in your oil to deal with.

 

[Avocet]

Thanks both. I had no idea such things as water finding paste existed! I'll do a bit of searching, thanks! Elsewhere, it has been suggested that the water source would be condensation. It's a single-skinned tank and I gather they're all double-skinned these days? Main problem is trying to find a home for what must be over 2000 litres of kerosene while I try to clean the darned thing!

 

[Burnerman]

Have you disconnected the pipe at the tank and decanted a gallon or so of kero into a clean container, just to see what's in there?
I have had black gunge in a copper pipe that had just a tiny fall over a long distance before, but as it was easy to access I just replaced the lot.
John

 

[Avocet]

Thanks John. Yes, I disconnected the union at the filter and then opened the gate valve on the tank outlet and ran some into a clean bucket. I got several great blobs of black gunge out into the bucket. I then disconnected the pipe just before it went into the house at the far end (about 30 yards) and put an air line on the tank end. More black gunge (though not a huge amount) came into a second bucket. Acces to the pipe will be a real problem though, because although it went roudn the perimeter of the house when the house was built, there has been an extension added since, and I reckon it goes right under the extension! There's no "fall" on it, but the oil tank is about 4 feet hgher than the boiler inlet.

 

[Burnerman]

There are additives which are supposed to help you here.....Boilermax is one, from Boilerjuice. I use it from time to time but I've no idea if it is helping anything.
I think if it was mine, I'd drain some more kero out of the tank, clean the pipe as you have, and see what comes out at the boiler end.
Maybe a Crossland filter unit at the boiler would help? Even if there was no element inside, there would at least be a bowl for the crap to settle in.
Bloomin' nightmare, the oil pipe under the house! It isn't in a duct by any chance?
John

 

[Avocet]

As it happens, I'm just trying to sort myself out with some suitable unions to cobble a car fuel filter assembly into the line. There's a Fram element in the car filter head at present, but I don't really care what sort - anything's got to be better than the rubbish "tea strainer" thing that's in there at present! Irritatingly, the tank is full, so there's a hell of a lot of oil to re-home! I'm hoping that I can continue to burn it over the winter to reduce the level in the tank - maybe changing the filter element frequently. The unit also has a drain cock at the bottom of thefilter housing so I can at least empt some of the crud out periodically.

Alas, no, I don't think the supply pipe is in a conduit! If I did have to prelace it, I'd just have to dig a new trench round the house. (Pity the previous owners paid for a nice brick drive)!

 

[Burnerman]

That sounds like a good move.....diesel filters have a drain off cock for any water that's in there. One in particular was the Bosch one fitted to the diesel Peugeot 205 - it was a huge alloy thing.
Good luck with it - I've never experienced this algae formation thankfully (yet )
John

 

[leakydave]

You can syphon water out at the bottom of the tank without taking the oil out.

 

[oilboffin]

I've got a pump with a brass weight on the tube sinks through the oil into the water.
Do not come into contact with the gunge if it's a bug you could catch something nasty,don't
laugh a friend of mine pulled a lump of lunge out of a tank and was bad for three weeks,high temp
sweating chills very bad. There is a biocides for tanks maybe BES have it, water paste turns pink when it hits water best of luck seems you've got quite a job on. Bob.

 

[Burnerman]

Hells bells never heard of that one
John

 

[oilboffin]

VerY true I saw him he looked bad, have you ever seen the jell in a header tank,a doc I know
Had a tank that got the jell in it and it had all black dots in it he reckoned they were eyes.
We took the tank out and replaced it,that jell in the open air looked weird.bbbrrrrrrrrrrr.

 

[Burnerman]

Jeez this is getting worse
Only managed to inhale dry rot spores a while ago, a full day of sneezing and retching.
John

 

[Agile]

Most tanks designed for oil take the outlet a little above the bottom and have a drain point right at the bottom to let water out from.