Plumbing against a wall

If you heat direct on the bricks, the bricks will explode tiny red hot pieces on you. Buy a cheap heat proof mat (abou two quid) and do the job safely. An alternate would be a metal shield (not as good though)

MrCheerful

MrCheerful said

OK - I've seen them for sale in B&Q.

Now, if I were to slide a heat proof mat behind the fitting, the fitting would then be sitting on the mat - I have only a mm or so clearance between the fitting and the wall.

Can I direct a flame right on to one of these mats? Will it take the heat away from the joint?

It's *brick* - it was made by baking clay in a very hot oven for a very long time. It will be fine; maybe a little sooty, but fine.

An ordinary ceramic wall or floor tile works just fine as well. I've not had trouble with a brick exploding, though - thought they were fired at a higher temperature than that needed to solder?

But will usually be surrounded by cement mortar which will explode and cause burns or serious eye damage.

It depends on how damp they are at the time. An ordinary house brick can hold a pint of water, although you have problems if one on an inside wall is doing so. A damp brick heated quickly will form steam inside and the steam can blow bits off some types of brick.

Colin Bignell

Yes, and yes, somewhat. It seems to interrupt the flow of hot gases. However teh copper should conduct well enough that this isn;t a problem.

Bricks should be OK for a bit of a blast, but the mat will avod unsightly marks.

Grunff said

LOL - point taken.

The Natural Philosopher said

Great stuff - thanks.

Your flame should be pointing at the fitting - not the mat. And the width of the flame should be no wider than the fitting. As such the mat won't be taking direct heat, it will simply be gaining heat from touching the fitting - and because it's rate of conductivity will be low then you are okay for long enough to fix the fitting.

Odd that you've got a fitting with a hole in it though! Time to move that dartboard I think..... ;)

PoP

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Twas the one and only leak I've had with capillary fittings - a Wickes elbow with a pin hole.

Very much so. I would be inclined to wear googles and just try and get the flame in the gap as best as possible.

PoP said

Job now done - thanks all for the advice.

I've been trying to figure that out myself. I have it here - and there is definitely a hole in it.

Ed Sirett said

I just used the mat to protect the wooden joist in the end - and the brickwork was fine when heated.