Flexible hose for heating oil supply?

[Nick]

I have to move my mothers CH fuel tank very slightly, probably not more than 600mm. At present this is plumbed with 15mm copper. Compression fittings used for the above ground pipework. The tank is 2500L,bunded and has an isolating valve. I would like to add a flexible hose with isolating valve when the tank is moved. Extra valve to minimize leakage and flexible to allow for expansion/contraction. Would an ordinary plumbing fitting be suitable for kero? I suspect not. If not, where can I find such a thing or should I visit the local hydraulic hose place? Most of the hose I use from these places is braided and not V flexible.

Many thanks, Nick.

[Tim Lamb]

In message , Nick writes

Cars often use braided hose for fuel. Bore and thread compatibility might be an issue.

[newshound]

Any hydraulic hose suitable for mineral oil should be OK. You don't need a great deal of flexibility for a static application and differential expansion.

[Dave Liquorice]

Personally I think fitting a bit of flexible hose is just asking for trouble. 600mm of copper will move less than 0.4 mm over at 40C temperature range.

16.6^10-6 * .6 * 40 = 3.984^10-4 m

It could be a problem if the pipe was rigidly held at both ends and was dead straight but any bend or curve will allow things to move that much without any problem.

[Michael Chare]

15mm is quite large for a domestic heating oil supply pipe!

I think most burners are connected using flexible pipes, however the ones I have seen are braided, or braided with an outer rubber? skin. These pipes are readily available but I am not sure if they are suitable for exterior use.

Arranging the pipe work so that any movement does not cause a problem might be a better solution.

[Grimly Curmudgeon]

I wouldn't - they fail often enough in boiler houses, where they're protected a lot.

[Nick Odell]

Personally I think that Dave's curved copper is a simple, elegant solution but if flexible hose solves more problems than it causes and you want to be sure it doesn't cause those problems then why not consider it as an inspectable item at the annual boiler service or a replaceable item on a periodic basis. After all, an engine cam-belt is destined to fail but it's the most convenient way of doing the job. We get round the problem by anticipating failure and replacing it.

FTR I lived for five years in a house with oil-fired CH and a flexible exterior hose in the fuel line. It never even crossed my mind that I ought to be concerned about its failure and in five years it never did.

Nick

[Jim K]

or it's more likely a microbore type size (10/12mm) with a plastic outer protective moulding around it

and they need replacing periodically as they (presumably) age and deteriorate

+1 a le Dave

Jim K