SWITCHED FUSED Connection unit

[Killalot]

Hi looking for some advice any help much appreciated. My combi boiler is connected to a switched fused Connection box which has a 3amp fuse in it. Then a cable from the switched box went straight to the boiler I've disconnected the cable straight to the boiler and put it too a double socket and ran a 3 pin plug with a 3amp fuse to the boiler. My question is will this be ok. If yes can I use the other socket on the double wall socket for my wireless thermostat receiver.

 

[telectrix]

from a BS7671 point of view it will be fine. as long as the stat requires only L, N, and E, then no problems afaik.

 

[Killalot]

from a BS7671 point of view it will be fine. as long as the stat requires only L, N, and E, then no problems afaik.

Thanks for the reply, if I do use the other spare socket on the double wall socket for the thermostat receiver will I need to put a higher rated fuse in the switched wall socket ?

 

[davesparks]

Hi looking for some advice any help much appreciated. My combi boiler is connected to a switched fused Connection box which has a 3amp fuse in it. Then a cable from the switched box went straight to the boiler I've disconnected the cable straight to the boiler and put it too a double socket and ran a 3 pin plug with a 3amp fuse to the boiler. My question is will this be ok. If yes can I use the other socket on the double wall socket for my wireless thermostat receiver.

The boiler can be fed via a plug if you wish, but it's generally better the way it was done originally.

If the wireless thermostat receiver is also connected to the boiler then I would say no you can't then supply it seperately. The thermostat needs to fed from the same feed as the boiler, and with some boilers it needs to be fed from the boiler itself.

If you have the boiler connected via one plug, the stat connected via another plug and then link the boiler to the stat you could have the plug pins of either plug being live whne you unplug it. Also if the fuse blows in one plug but not the other parts of the system will appear to be dead when they are not.

 

[Taylortwocities]

You should have retained the FCU and wired the wireless receiver into that together with the feed to the boiler. That way (as above) you have a single point of isolation for the heating controls+boiler.
You must have this, it is a MANDATORY requirement.

 

[Killalot]

Thanks for the replys. The reason I put a plug on was when you switched the boiler off it wasn't dead it was still live from the switched wall socket. I only found out it was feed from the switched socket when the boiler went off and I couldn't work out why the fuse had gone on the switched socket.The switched wall socket had been boxed in behind a shelf. This is the set up now it seems to be working fine.

 

[Taylortwocities]

s. The reason I put a plug on was when you switched the boiler off it wasn't dead it was still live from the switched wall socket

Of course! If you have a kettle plugged in to a socket there will still be power going to it.

Please…It might be working fine but it is not correct.
There must be a single point of isolation. There isn’t. You have two.
It needs doing properly. I suggest you either put the FCU back with both the boiler and the receiver feeding from it, or fit the FCU (13A fuse) in the feed to the socket.

 

[Killalot]

Of course! If you have a kettle plugged in to a socket there will still be power going to it.

Please…It might be working fine but it is not correct.
There must be a single point of isolation. There isn’t. You have two.
It needs doing properly. I suggest you either put the FCU back with both the boiler and the receiver feeding from it, or fit the FCU (13A fuse) in the feed to the socket.

The single point of isolation is pulling the plug out,with the plug removed the boiler has no power going to it. Before if you turned the boiler off at the boiler it was still live.
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[davesparks]

The single point of isolation is pulling the plug out,with the plug removed the boiler has no power going to it. Before if you turned the boiler off at the boiler it was still live.
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But with the thermostat unplugged and the boiler plugged in you still have a live supply at the thermostat from the boiler.
There is no reason to do this in a domestic heating installation and it is dangerous.

 

[Killalot]

But with the thermostat unplugged and the boiler plugged in you still have a live supply at the thermostat from the boiler.
There is no reason to do this in a domestic heating installation and it is dangerous.

Hi, if any work is needed at the boiler I would pull both plugs out. I appreciate your advice, the way it was set up before though wasnt ideal turning the boiler off at the boiler it was still live unless you pulled the fuse out the FCU. The FCU though is boxed in under a shelf it took me 10 minutes to get all the silicone off to get the shelf off the wall.
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[davesparks]

Hi, if any work is needed at the boiler I would pull both plugs out. I appreciate your advice, the way it was set up before though wasnt ideal turning the boiler off at the boiler it was still live unless you pulled the fuse out the FCU. The FCU though is boxed in under a shelf it took me 10 minutes to get all the silicone off to get the shelf off the wall.
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Yes you would pull both plugs out, but that doesn't mean that anyone else would.

If this problem existed before then it sounds like that was a potentially dangerous situation.

So it appears that you have taken a non-standard and potentially dangerous setup and replaced it with a different non-standard and potentially dangerous setup.

Most electricians have experienced going to houses where the previous owner/husband/son/father 'did the electrics themselves' and found dangerous situations that have the potentially to kill them.

 

[Killalot]

Yes you would pull both plugs out, but that doesn't mean that anyone else would.

If this problem existed before then it sounds like that was a potentially dangerous situation.

So it appears that you have taken a non-standard and potentially dangerous setup and replaced it with a different non-standard and potentially dangerous setup.

Most electricians have experienced going to houses where the previous owner/husband/son/father 'did the electrics themselves' and found dangerous situations that have the potentially to kill them.

Hi, I'll hardwire the thermostat receiver into the boiler so then there is only 1 point of isolation.