Bonding a bathroom to be tiled

[Adam_151]

Need to get our bathroom bonded, worked out I can keep the bonding cable in zone by positioning the patress for the FCU for the pump unit for the shower inside the bathroom in Z3 instead of outside the bathroom and running the cable vertically in line with that

But now got another problem, most of the pipes enter the bathroom under the floor, the hot and cold to the sink and bath, and the CH pipes do, the shower pipes will be comming from above, and they will be 0.75m crome tails on the end of aprox 15m of PVC, so no bonding required for them (I think!... unless we have very conductive water!)

Anyway, we are going to have the floor tiled eventually, and while I might be able to bond the hot and cold at both* bath and sink, the radiator pipes can only be bonded under the floor, so I might as well get all 4 on their point of entry to the bathroom and be done with it, Now I see I have three choices:

1) Ignore rules about accessable connections and just put BS951 clamps under the floor

2) Reach further along and put the clamps on boundry with the hall, or actually under the hall... which is carpeted so more accessable than the bathroom, but its not really accesable in the way that we don't want the carpet lifting atm, so its lucky I culd put the clamps in by reaching across.

3) Solder the bonding cables, this is what I'm leading to at the moment, but a few thoughts on my mind:

a) what do you use to solder them, I'd expect a blow lamp might end up melting the insulation, and while my 18w antec is great for electronics work... , something this suitable?

b) What solder do you use, am I looking for big electrical solder, or small pluming solder?

c) Do you cover the soldering with anything?

d) How does anyone in future know its there, and the method of connection used?




*I would have to bond it at both, because if I just bonded it at one branch, sods law says someone is going to insert a piece of pvc in that branch upstream of the bond... compromising the bond to the other branch

 

[dingbat]

1) Ignore rules about accessable connections and just put BS951 clamps under the floor

Don't do that - you know it's wrong!

2) Reach further along and put the clamps on boundry with the hall, or actually under the hall... which is carpeted so more accessable than the bathroom, but its not really accesable in the way that we don't want the carpet lifting atm, so its lucky I culd put the clamps in by reaching across.

Accessibility includes the knowledge of where connections are. Unless you intend to build a nice, obvious screwed hatch, with a notice on the landing to inform future occupiers this is also not correct.

3) Solder the bonding cables,

Best of luck if there's any water in the pipes.

However, if you have yet to do this install your best bet is to fit a soldered crimp lug to all relevant pipework.
http://www.gasafe.uk.com/product/?pid=1626

b) What solder do you use,

Plumbers.

c) Do you cover the soldering with anything?

No, but do wipe off the flux residue.

d) How does anyone in future know its there, and the method of connection used?

They test the electrical continuity of the exposed and extraneous conductive parts and bingo, all is well. There is no need to know how the bonding is achieved, as long as it is effective, but should there be a problem, screwed (i.e. non-permanent) joints would need to be accessible for inspection, while solder is, effectively, for life!

 

[pcboffinuk]

Adam,

To be honest I have mixed feelings about this rule...

As far as I can see, a properly tightened earth clamp is very unlikely to come undone, like a junction box screw might. I would think the amount of vibration or disturbance that might cause that might well also cause soldered connections to come loose?

I guess there is the possibility of the clamp rusting over time if there is a leak, but I don't know if that is a likely issue.

From personal experience, even when taking care, I've found that I've had to test crimped connections and redo them because they haven't passed the 'pull test' - yet they can be completely sealed in for ever....

Personally I would want to be very confident about my soldering before I relied on such a connection - not to mention having to drain the system, etc.

Mind you, that prolly doesn't answer the question, so I'll let one of the more experienced experts comment...




Gavin

 

[Adam_151]

1) Ignore rules about accessable connections and just put BS951 clamps under the floor

Don't do that - you know it's wrong!

3) Solder the bonding cables,

Best of luck if there's any water in the pipes.[/quote]
Yes, I know, going to have to drain them

However, if you have yet to do this install your best bet is to fit a soldered crimp lug to all relevant pipework.
http://www.gasafe.uk.com/product/?pid=1626[/QUOTE]
The pipes are already in place, but I could fit them, they look interesting? any idea what cable size they are designed for? I'll obviously be wanting to put in either 2x4mm² or 1x4mm² (the last one on the 'string'), and endfeed, urgh... that seems to be a plumbers website, does anyone make a version for sparkies that doesn't require as much plumbing skill?

d) How does anyone in future know its there, and the method of connection used?

They test the electrical continuity of the exposed and extraneous conductive parts and bingo, all is well. There is no need to know how the bonding is achieved, as long as it is effective, but should there be a problem, screwed (i.e. non-permanent) joints would need to be accessible for inspection, while solder is, effectively, for life!

I guess that works in most cases, but if a tiny piece of pvc was put in just before a hot tap for example, testing between the taps would show bonding incomplete (all pipes are bonded on entry to bathroom, remember), but the tap is going to be at the potential of the bonding unless you connect it to something at a different potential (which you are not going to have in the bathroom anyway) and form a circuit, allowing a currrent to flow and a potential to be developed across the high resistance section (a small piece of water filled pipe).

*Wonders if he has explained his thoughts clear enough *

 

[dingbat]

Plumb it all in plastic, rads included and forget about extraneous conductive parts. That's how I'm going to do my bathroom!

 

[Adam_151]

Plumb it all in plastic, rads included and forget about extraneous conductive parts. That's how I'm going to do my bathroom!

Lol, well if it was a new bathroom I would, but its an existing bathroom due to be refitted with bathroom 'applicances' (?!!) in the same place as they are now

 

[JohnD]

You say the radiator pipes can only be bonded under the floor; how true is that? Do you mean that the pipes are accessible above the floor but you don't want to bond them there?

You can bond the hot and cold behind the bath panel where they will not offend anyone's sensitivities, and if the copper pipes are soldered all the way to the basin, you do not need to bond them again if you don't feel like it. But you could bond then behind the pedestal if there is one. So you can have all your bonding connections accessible. They do not go rusty, I think they are nickel plated brass, not steel. You will find it very difficult to solder to a copper pipe if there is any damp in it - not just drained. The steam will cool it down.

The shower pipes you can easily bond to the lighting circuit in the loft before they come through the ceiling, you might have to run a conductor up there from the ring but this can be done out of sight in the airing cupboard if you have one, or the soil pipe duct if it is inside.

 

[Adam_151]

The radiator pipes come from the hall, under where the door frame is under the liftable floor, and then they disappear under a concrete floor , where which they rise through to go to the radiator, If I wanted to get a cable down to there, I'd have to chase it down from above (I'd have to create the zone somehow) and then the radiator is going to be a chrome towelrail one, which isn't going to look good festooned with earth clamps...

(I beleive the bathroom was two separate rooms once)

 

[plugwash]

if you are going to solder to the pipes then the following should work

1: drain the pipe
2: bind the earth cable to the side with thin wire (doesn't really matter what its just to hold it while soldering)
3: solder it up