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[colbee]

Please can anyone explain this:
I am renovating a mid-20s semi which was professionally completely re-wired last year.
I am making frequent use of a 2000 watt steam wallpaper stripper and a 2000 watt hot-air gun (not both at the same time, of course). So far I have stripped five layers of wallpaper (with each layer having been overpainted) from two good sized bedrooms and a similar number of coats of paint from those rooms and hall, stairs and landing. This has meant hours of use for the steamer and gun but they never missed a beat.
Now I am attacking a ground floor room and am repeatedly beset by the steamer and gun knocking out all the sockets in the house -upstairs, downstairs and the cooker; but they don't trip the consumer unit. After a few minutes everything works again.
The heat-gun did it first, repeatedly and often; I thought it was defective so I bought a new one, but the new one does it too, then the steamer started it!
Help :(

[ericmark]

Except for very rare auto resetting RCD’s at over £300 each I would not expect to see any normal house with one fitted nothing in the house wiring, socket outlets or consumer unit is auto re-setting.
However appliances do often have auto re-setting over heat and over current devices and it is possible being closer to the consumer unit could raise the voltage just enough to start them tripping. As they trip it tends to affect the protective device and they do then trip more often.
If it is a failure on the sockets, then we are looking at bad connections, and these can produce excessive heat and there is a risk of fire.
As to finding the fault best tool I have found is my nose. I sniff around and quite often you can smell the burning. Failing that it can be very long winded. First place I would look is the consumer unit. Discolouration is another good sign.
Most houses have multi ring mains and it is common to split upstairs and downstairs which would explain the change when moving.
If you have three separate supplies as you indicate all going off together but your lights are still working then the most likely common item to all three supplies is the RCD so I would be looking at all the cables in and out of RCD for lose connections could be RCD itself of course. If you go into the consumer unit then remember this fault may mean the RCD and Isolators could be faulty so don’t assume it’s dead. For this reason, I would recommend you get a spark to look at it.
All best Eric

[colbee]

Thanks for the advice Eric. The consumer unit has a label stating:
'This installation, or part of it, is protected by a device which automatically switches off the supply if an earth fault develops. Test quarterly by pressing the button marked T or Test. The device should switch off the supply and should then be switched on to restore the supply. If the device does not switch off the supply when the button is pressed, seek expert advice.'
In fact this device works- when the button is pressed it flips a switch, which has to be flipped back to restore supply.
I don't know if this is relevant because, as I said, the supply resumes of its own accord and there is no indication (for example, flipped switches) on the consumer unit.
There is no sign or smell of burning at the sockets or CU and I have checked the tightness of the socket connections. It's just a mystery; sometimes I can work for an hour or two before getting a shut down, other times it happens after only half an hour or so. Then, when it restarts it can shutdown after only a few minutes.
I don't want to call the installers back because I am already dissatisfied with other aspects of the job which I have rectified myself on the basis that the installers did such an awful job I would not have them back (if that makes sense!).

[ericmark]

The question has to be how do you know the supply has failed? Have you tried other things in the socket? Or just plugged the thing you are using in another socket? There is nothing that should reset itself on the house supply.
There is however often over temp and over current devices that would work exactly as you describe that are often built into heating devices.
The instructions on how the test the manual operation of an RCD are standard and would have nothing to do with the fault.
all best Eric

[colbee]

Hi Eric and thanks,
I know the supply has failed because when the steamer/ heat gun shut down I first tried another socket in the same room - no power. Then I plugged in my mains drill in the same room and all the other rooms including the kitchen and the cooker point - all no power. Lighting is ok.
There are 3 separate circuits for upstairs/downstairs/cooker.
Sorry for being such a pain.

[ericmark]

It seems it must be your RCD although auto reseting units are very rare. I think it is more likely there is a fault with the RCD than it is an auto reseting one. It is the only item common to all circuits that fail but not common to circuits like the lights which don't fail so how ever remote it seems I can't see it being anything else.

All best Eric

[colbee]

Much obliged Eric, thanks for your trouble.