Help please with a room thermostat.

JohnB47

Something like this is cheap and invaluable for testing if a wire is 'live' or not. The idea is that you touch the 'flat blade tip' end against a bare wire while holding a finger against the metal contact at other end if the screwdriver. Internal circuitry lets a tiny amount of current to flow, enabling a ltttle built-in led to light if there's mains voltage present. I always use one of these to test that there's mains voltage present first and then again that it's absent after I've turned the electricity off. If you don't follow this routine every time, you can't know if the screwdriver is working.
https://www.screwfix.com/p/roughneck-electrical-mains-tester-screwdriver-100-250v-ac-slotted-3-5mm-x-130mm/8606x

fenwick458

TUVOK said:

If I turn of all power to the house via the consumer box, that should take care of all live wires?

yeah assuming you know how the house is wired, and you defiantly only have one consumer unit. A customer once called me out to fix his "dangerously wired house", he said it was so wired wrong because when he knocked off all the power at the consumer unit but the shower was still live. turns out, I moved the rest of the coats and boxes from under the stairs cupboard and there was another old wylex one way consumer unit just for the shower!
so a basic tester is advisable, unless you are really sure of exactly where to turn the power off so you get everything.

Jeepers_Creepers

Yup.

Good luck - please report back :-)

TUVOK

Thanks again and yes, I will check for any other fuse/consumer box's in the property.
I'll be ordering today the Drayton from Screwfix.
It will be next weekend before I can change the stats over, but will let you know how it has gone.

TUVOK

Hello, I purchased the Drayton RST2 from Screwfix (£17-99) and did the change over today.
All would appear to have gone well even to the fixing holes being in the same place!
Being able to regulate the heating should hopefully make a lot of difference to my son's heating bill!
A grateful thank you for the detailed, most helpful answers and solutions to my initial query.

Jeepers_Creepers

Cool. Thanks for coming back :-)

Or should I say, "Phew! He's back!" :-)

FreeBear

JohnB47 said: Something like this is cheap and invaluable for testing if a wire is 'live' or not. The idea is that you touch the 'flat blade tip' end against a bare wire while holding a finger against the metal contact at other end if the screwdriver. Internal circuitry lets a tiny amount of current to flow, enabling a ltttle built-in led to light if there's mains voltage present.

Some of those things are real dangerous. If any part of the internals go short circuit, you could get a very nasty shock. Much safer to use a fully VDE compliant probe.

This one is safer than the Roughneck death stick - https://www.screwfix.com/p/di-log-pl107n-1000v-non-contact-voltage-indicator/162jp

Jeepers_Creepers

JohnB47 said:

Something like this is cheap and invaluable for testing if a wire is 'live' or not. The idea is that you touch the 'flat blade tip' end against a bare wire while holding a finger against the metal contact at other end if the screwdriver. Internal circuitry lets a tiny amount of current to flow, enabling a ltttle built-in led to light if there's mains voltage present. I always use one of these to test that there's mains voltage present first and then again that it's absent after I've turned the electricity off. If you don't follow this routine every time, you can't know if the screwdriver is working.
https://www.screwfix.com/p/roughneck-electrical-mains-tester-screwdriver-100-250v-ac-slotted-3-5mm-x-130mm/8606x

I remember as a child taking one of these apart to 'see how it worked'. I was amazed at how crudely it was made, and when reassembling it was aware that only millimetres lay between the user and a bad case of death. Worse than that, the spring betwixt the neon and the resistor was almost slipping over the resistor and could have by-passed it quite easily by the looks - so we are talking mere fractions of a mm between youknowhwat.

But still, I've never heard of anyone being shocked using one of these.

The ones sold now must surely be pretty well built to be certified for use; 'TUV and GS approved' sounds darned good to me, whatever it means...:-)