Bonding Radiators

Gryzor

Recently bought a house that has all the radiators bonded. Radiators are plumbed with qualpex.

Do they need to be bonded, or can I remove it??

Dtp1979

Gryzor wrote: »

Recently bought a house that has all the radiators bonded. Radiators are plumbed with qualpex.

Do they need to be bonded, or can I remove it??

Seems like your sparks did a good job. Why on earth would you remove it. It's there for your safety. I'd be more concerned with the rough plumbing of running qualpex straight up to a radiator.

Gryzor

Dtp1979 wrote: »

Seems like your sparks did a good job. Why on earth would you remove it. It's there for your safety. I'd be more concerned with the rough plumbing of running qualpex straight up to a radiator.

Thought I read somewhere that if the pipes to the radiators weren't metal, they weren't really required.

Bruthal

Dtp1979 wrote: »

Seems like your sparks did a good job. Why on earth would you remove it. It's there for your safety. I'd be more concerned with the rough plumbing of running qualpex straight up to a radiator.

It would appear to be there for your safety. But its going to do nothing on a radiator which is isolated from the earthing system.

In fact it will introduce voltage to the isolated radiators during the fault which bonding is the defence against.

Risteard81

Bruthal wrote: »

It would appear to be there for your safety. But its going to do nothing on a radiator which is isolated from the earthing system.

In fact it will introduce voltage to the isolated radiators during the fault which bonding is the defence against.

Indeed. Bonding where it is not required can actually reduce safety.

Cerco

What about the water in the radiator providing a path back to boiler?

Bruthal

Cerco wrote: »

What about the water in the radiator providing a path back to boiler?

Contrary to what 99.9 percent believe, water is as good as an insulator after a short distance at the CSA of a heating circuit pipe.

Risteard81

Pure water is non-conductive. It is the impurities in the water which are conductive.

Cerco

Risteard81 wrote: »

Pure water is non-conductive. It is the impurities in the water which are conductive.

Agreed but you will not find pure water in a radiator. The water is full of impurities even before it hits the F/E tank. Magnetic devices are used to gather impurities in many heating system.

Bruthal

Cerco wrote: »

Agreed but you will not find pure water in a radiator. The water is full of impurities even before it hits the F/E tank. Magnetic devices are used to gather impurities in many heating system.

Yes, but water is still so poor a conductor, that water in qualpex pipes will offer no connection to anything.

I just got jug of water. Probes from meter immersed about 5 inches apart. Result... 50k ohms.

Cerco

Bruthal wrote: »

Yes, but water is still so poor a conductor, that water in qualpex pipes will offer no connection to anything.

I just got jug of water. Probes from meter immersed about 5 inches apart. Result... 50k ohms.

That's interesting. What is a CSA?
Similar situation with a stainless steel sink with taps connected
via flexible pipes to bonded copper pipes. Should the taps &
or sink be bonded?

beanie10

Ideally the taps and sink/draining board should be bonded as these are the touch points. If copper pipes are bonded electrician should rest resistance between bonding straps and taps to make sure to make sure of earth continuity. Draining board should be cross bonded from taps by suites le clip.

Bruthal

Cerco wrote: »

That's interesting. What is a CSA?
Similar situation with a stainless steel sink with taps connected
via flexible pipes to bonded copper pipes. Should the taps &
or sink be bonded?

The CSA varies because the path between pins won't simply be a narrow wire shape, it will be like a rugby ball shape. The result in a 15mm pipe would be higher. The pins surface area would be a factor too. But it still shows water resistivity is very high.

Went hands greatly increase a shock when contact is made across a potential difference. But the water is like an ultra thin film and a CSA matching the contact area. So the water CSA:conductor length ratio is very large. And that criteria means its a much lower resistance than dry skin. Skin salts are a factor also. But don't forget, even with the wet hands and severe shocks, the current flow is still small.

The water in the pipes, CSA:conductor length ratio is tiny, so even though the first scenario of wet hands leads most to believe water is a good conductor, its not.

Cerco

Do you mean " conductor surface area" or contact surface area or something else.
What pins are you referring to?
Interesting info , thanks.

Bruthal

Cerco wrote: »

Do you mean " conductor surface are" or contact surface area or something else.
What pins are you referring to?
Interesting info , thanks.

Pins are the multimeter pins in the water test.

The conductor surface area in my post with regard to wet hands is the surface area of wet fingers etc in contact with electrical parts. The length of it as a conductor is the thickness of the water between skin and points being touched. So the conductor length is microns. Which means that even though water is a poor conductor, such a thin film will be a better conductor than dry hands.

salmocab

The radiators should not be bonded if the pipes are qualplex, this has come up for me a few times over the last few years because of SEAI grants which looked for bonding in the hot press regardless of copper piping or not but the regs actually say not to as it is not desirable to introduce a path to earth where something is considered isolated.

Gryzor

Interesting discussion and a solid answer to my question methinks.

Recently replaced the kitchen sink, didn't realise it needed to be bonded. It is plumbed with copper. The old one was not bonded either.

beanie10

Are radiators meant to be bonded at all even if they are plumbed in copper? Is 10sq earth to hotpress and bond copper pipes there sufficient nowadays?