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John Rumm John Rumm is offline
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Default Outside light query

On 10/02/2017 12:55, Huge wrote:
On 2017-02-10, Dave Liquorice wrote:
On Fri, 10 Feb 2017 10:37:02 +0000, Bob Minchin wrote:

An outside container is very difficult to fully seal as thermal
expansion/contraction will act as a pump admitting small amounts of
water vapour laden air. The water condenses and stays inside and on the
next heating cycle the air gets pushed out but the water does not and so
it slowly builds up as the cycle repeats.


Double plus 1. Not many people realise/know that.

So although holes seem bodgy it's the only way. Only need one at the
lowest point and it doesn't need to be very big 1mm is ample. Much
bigger and a decent blow will manage to force water in, not to
mention letting in spiders or other wild life.


The spiders get in anyway. I have no idea how.

(Over the last few weeks I have dismantled all the outside electrics
in the so-far fruitless search for the nuisance RCD trips, and they
all had spiders in them. Even the IP44 junction boxes.)


Bit like one of my PIRs:

http://wiki.diyfaq.org.uk/index.php/...nTheWiring.jpg


--
Cheers,

John.

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