Fusing the neutral?

[bilge rat]

I recently did a fault finding exercise on a Baxi central heating boiler at my sons house. The plumber who installed it had wrongly connected a wireless programmer. An easy mistake for a plumber to make as the installation manual showed two different versions of the same circuit diagram.
During the check I was horrified to find the connection block within the boiler unit, had both live and neutral conductors fused. Now the last time I worked as an electrician was in the era of the 16th edition. Fusing the neutral was always a no no because of the dangers that could result in the neutral fuse blowing leaving the appliance apparently dead yet still having a live connection to it.
Is it possible that a large company like 'Baxi' could make such an error or have the Regulations changed considerably.
Your views please.

 

[Dan]

Welcome to electriciansforums.net. Stick around I'm sure you'll like the forum.

 

[CRAGS]

Hi and welcome

 

[Top Cat]

Hi bilge rat, welcome to the forum. The first thing you have to realise is that you said a plumber connected it! Look though some of the past posts and you will see that we do not have a lot of time for plumbers!

I will stop now or i could be still on at midnight about f in plumbers!

 

[bilge rat]

I agree about plumbers but the fused neutral is put into the boiler unit by the manufacturer Baxi).

Thanks for the welcome

 

[Top Cat]

I agree about plumbers but the fused neutral is put into the boiler unit by the manufacturer Baxi).

Thanks for the welcome

Funny you should say that. About six months ago i was connecting a boiler and thought, there is a fuse in the neutral on the pcb, thought to myself no, they wouldn't do that i was in a hurry so left it. Now you have me thinking again!

 

[HandySparks]

Got to be worth getting an answer out of Baxi on this one?

 

[bilge rat]

Got to be worth getting an answer out of Baxi on this one?

Thanks for that handy, I have E mailed them but so far no reply.

 

[snowhead]

If you go to the Baxi website and download the install manual for Megaflo 2 system boiler compact, there is indead a fuse in the neutral and live at the incoming terminal block.

There isn't in the 105he tho'

 

[Top Cat]

If you go to the Baxi website and download the install manual for Megaflo 2 system boiler compact, there is indead a fuse in the neutral and live at the incoming terminal block.

There isn't in the 105he tho'

But why?

 

[snowhead]

But why?

I'm not Baxi, I can't answer that, but the fuse is inside an appliance so won't be under the regs.

I see equipment with switched neutrals and permanent lives.

 

[westom]

But why?

Fusing a neutral wire connected to any load is absolutely wrong. Fusing the internal connector that connects to the neutral can be for reasons completely different. For example, a design may support numerous configurations including those that have no neutral connection. Reasons for fusing inside a controller can be for reasons well beyond what an electrician may understand. Without the specific schematics, nobody can say anything more. An engineer who designed that controller probably fused both AC wire lines for specific reasons. Which is electrically different from fusing a neutral wire that feeds that controller.

 

[Des 56]

That's a reasonable answer above, If there was a fuse in the neutral,it would not be for external controls

More than likely there would be alternative neutral connections that were not via the fuse for any external loads

 

[LukeBuckaz]

maybe they fused the neutral 'jut in case' said plumber got the polarity the wrong way round, probably not, probably something much more technical than this!

 

[Darkwood]

most of you are crossing over bounderies here.. its a control board and subject to different rules and regulation to what we are used to, yes agree that fusing a neutral in our installations could kill in the worst case senerio but on a control board this hazard dosn't normally exist (dependent on circuit board design)it will just stop the board working, many boiler manufacturers etc have neutral fusing but it dosn't pose a safety hazard, remember to get their stamp of approval and on to the british market they have to comply to their own reg's... TIN HAT ON!!!.... anyone explain to me what exactly is dangerous about this then i will argue my corner!