On Sun, 15 Feb 2015 18:57:38 +0000 (GMT), Dave Plowman (News) wrote:

In article ,
Huge wrote:
On 2015-02-14, wrote:
On Saturday, 14 February 2015 16:38:04 UTC, Kevin wrote:
I see that many suppliers now offer both SP and DP versions of
switched sockets, with DP up to 50% dearer for a given make. What
governs which version one should use?

You can't use a switched one of any variety for supplying a boiler.

I think you mean "may not" rather than "cannot", since my boiler's been
plugged into a switched socket for 21 years to my knowledge, and it works
just fine.

Quite. I'd rather have a boiler fed via a plug and socket - single or DP
switched - than an FCU, since you can unplug it. A definite air gap is
more confidence building than any switch.

The MK Logic Plus sockets quote a DP 3mm air gap - the same as a shower
pull-switch. I've used them where I want to switch off but unplugging would
be awkward.
--
Peter.
The gods will stay away
whilst religions hold sway