Discoloured paint below chimney

[Ricco1]

My boat suffers from this, as do some others I've seen. I'm sure most of you are familiar with it: The paint resembling some similarity to it original colour but stained with a black mess.

 

First, is it burning wood or coal that causes this? And might t cut or something similar make it look better?

[Jigsawged]

There may be several reasons to do with the fuel and the temperature that it is burnt at. Wood in particular can cause a tarry stain if it isn't burnt at a high temp. You may find that using a chimney with a built in liner will reduce or eliminate the problem. I recall an explanation that with a single skin chimney, tar from the fuel builds up inside, drips down and out from the base of the chimney but with a double skin any such deposit will return down the flue where hopefully it will burn off. You may find that over time it builds up inside the flue and will take some vigorous sweeping to remove it.

 

I haven't come across anything that will remove the staining from the coach work but I did see something on the forum a few weeks ago where someone recommended a particular cleaning method/product. Perhaps a search on the forum will turn it up, if some kindly soul doesn't reply with a full fix.

 

Edited to correct predictive bloody text

Edited September 30, 2013 by Jigsawged

[Capt Ahab]

Try some very gentle cutting compound like G6 with water (not T Cut which is too abrasive).

http://www.autopaintsbrighton.co.uk/farecla-g6-compound-400g-tube-213-p.asp

[Grace and Favour]

In our first year of boating we too suffered with the rather caustic tar deposits/stains from our chimney.

 

We took a number of steps to remove the stains, and prevent further damage.

 

Perseverance and a few hours gentle cleaning of the stains with a soft cloth and methylated spirits removed most of the tell-tale trail of carbon nasties. (I did this over several months - which really did seem to offer an excellent result - (I would recommend you try solvents before abrasives such as T-Cut etc)

 

To prevent further staining - burn good quality (low tar) fuels (such as smokeless briquettes) and, most importantly - get a twin walled chimney (preferably bespoke for your boat) where the inner surface/lining, fits snugly within the chimney collar on your roof, whilst the exterior surface fits snugly over the collar.

 

You will never suffer those tar stains again.

 

(I had a chimney made with both liner & exterior made of stainless steel - a purchase I will never regret)

 

Edited to add: "and stuffed the chimney void with rockwool to insulate - - - makes the chimney even more efficient)

Edited October 13, 2013 by Grace & Favour

[Phil Ambrose]

I have a twin wall/double skin chimney which is fine, however I did gey some staining cause by the gunge condensing on the coolie hat and dripping down Solution was simply to remove the coolie hat this cured the staining and no problems occurred by not having a coolie hat.

Phil

[trackman]

I support Phil re coolie hats. We gave up using one, as it did exactly as he says. We have had no problem without one when the stove is in use. When it's not we remove the chimney and cap the flue.

An insulated double skinned chimney is best at stopping condensation inside the chimney. Its liner needs to project down below the top of the roof flange into the flue so any drips there are still are directed into the flue, not between chimney and flange.

I insulated a s/s chimney by filling the void between liner and outer skin with high temperature builders foam.

I found a stain removing product at a chandlers that did shift the tarry stains without paint damage. It was made by a polish maker, I forget which, I haven't needed it for years and don't have it handy. Possibly International. It took several applications and some effort to shift it all.

[Higgs]

Make sure that whatever is coming up the chimney and condensing on the inside of it cannot escape through the base and onto the roof. My own flue has a fairly good wrapping of exhaust bandage as it exits the roof, avoiding too much transfer of heat to the roof at that point. The extension chimney also fits inside the flue.

 

I don't use a coolie hat, for the reasons already stated, but will be buying one for those occasions I need to leave the boat and haven't quite killed the fire. The fire will eventually die and then the stove would be prone to heavy rainfalls, so the coolie hat is simply to keep the rain out when the fire is out. Otherwise, it is capped off.

Edited October 6, 2013 by Higgs

[bizzard]

I don't use an overlapping chimney because of this reason. If you find a bit of pipe, stainless steel preferably that fits easily INSIDE the collars orifice, stick it in lightly with some silicon so that it will keel over easily without any damage if hit by a low bridge ect, and no more gunge will ooze out from under an overlapping base.

 

eta. You could of course fit your overlapping chimney back over the pipe I mentioned if you want to retain it.

Edited October 6, 2013 by bizzard

[bigcol]

this week using fire, lots off staining

 

rang up smokies joes, great website

 

got 22inch liner fitted

 

problem solved

 

col

[Ricco1]

Would there be any value in using silicone sealant around the chimney? Mine overlaps... I've already removed the coolie hat, thanks for that advice.

[onionbargee]

paint brush cleaner, hot water and elbow grease gets it off, ( doesnt harm the paint)

[by'eck]

I have a twin wall/double skin chimney which is fine, however I did gey some staining cause by the gunge condensing on the coolie hat and dripping down Solution was simply to remove the coolie hat this cured the staining and no problems occurred by not having a coolie hat.

Phil

 

With a single skinned chimney I found the coolie hat actually reduced the condensation drips. I agree a double skinned one is a better solution though.

[Ray T]

I bought a double skinned chimney, Wrapped the inner liner with exhaust wrap then filled what was left of the void with fire resistant expanding foam.

 

This keeps the inner liner warm and the outer skin cold, never had any tar staining issues.