Earth in hotpress

dudeeile

Earth wire is connected to the cold water feed coming from the attic tank and then continued over to the copper pipe on the right which is an ensuite feed.

I'm installing a new hwc and was hoping to use pvc piping to continue the cold feed to the cylinder but am I better using copper so that the earth is bonded to the cylinder?

meercat

dudeeile wrote: »

Earth wire is connected to the cold water feed coming from the attic tank and then continued over to the copper pipe on the right which is an ensuite feed.

I'm installing a new hwc and was hoping to use pvc piping to continue the cold feed to the cylinder but am I better using copper so that the earth is bonded to the cylinder?

You can just add 10mm earth to the last bonding clip and connect a new bonding clip to the cylinder. Use a small bit of copper pipe to the cylinder to get a good connection

Bruthal

Probably better having copper pipes as the connection to hw cylinders anyway.

JimToken

Realistically all you have there is probably a few pieces of copper and the main metallic services are in plastic.

Good read on the theory below
https://electrical.theiet.org/wiring-matters/years/2019/75-may-2019/to-bond-or-not-to-bond/

Sleeper12

From a plumbing point of view, qualpex is fine feeding cold to bottom of the cylinder but never off the top of the cylinder. If the thermostat failed then the qualpex off the top of the cylinder would melt.

Bruthal

More from a morality view:D

JimToken

Sleeper12 wrote: »

From a plumbing point of view, qualpex is fine feeding cold to bottom of the cylinder but never off the top of the cylinder. If the thermostat failed then the qualpex off the top of the cylinder would melt.

Has this actually happened

2011

Sleeper12 wrote: »

If the thermostat failed then the qualpex off the top of the cylinder would melt.

Really?
Have you ever seen this?

Qualpex is rated for 92 Degrees C indefinitely and has a 114 Degree short term rating.

https://pdf4pro.com/amp/cdn/qual-pex-plumbing-amp-heating-pipe-pipelife-ie-2d695a.pdf

Wearb

There have been cases of deaths from cylinder thermostats failing. This keeps boiling the water into the expansion vessel (open system) Because of the slight head, this water will be at least 100C (ignoring house height above sea level).

The instance I'm thinking of, was where the expansion (plastic) tank eventually softened enough to fail and dumped its boiling contents on the ceiling and then through it to a sleeping occupant below. Of course even then the boiling water continued to flow through the expansion pipe.
Doesn't bear thinking about does it.

JimToken

Wearb wrote: »

There have been cases of deaths from cylinder thermostats failing. This keeps boiling the water into the expansion vessel (open system) Because of the slight head, this water will be at least 100C (ignoring house height above sea level).

The instance I'm thinking of, was where the expansion (plastic) tank eventually softened enough to fail and dumped its boiling contents on the ceiling and then through it to a sleeping occupant below. Of course even then the boiling water continued to flow through the expansion pipe.
Doesn't bear thinking about does it.

Lol sounds like something out of a horror movie

That could have been part.of the reasoning for the reset buttons, I thought it was mainly down to thermostat failure

dudeeile

meercat wrote: »

You can just add 10mm earth to the last bonding clip and connect a new bonding clip to the cylinder. Use a small bit of copper pipe to the cylinder to get a good connection

Okay got that. Ideally I would like to remove the copper feed you see on the left and the attached earthing, add in a new valve then qualpex down to the cylinder, I can add a few inches of copper off the cylinder and just connect the earth up to that. Am I making sense?

I'd like to avoid burning my house down while at it.

Sleeper12

JimToken wrote:

Has this actually happened

2011 wrote:

Really? Have you ever seen this?

Yes. It's against building regulations (AFAIK) and against the manifacturer specifications for its product. You can never use qualpex on the flow & return right at gas or oil boiler either.

JimToken

Sleeper12 wrote: »

Yes. It's against building regulations (AFAIK) and against the manifacturer specifications for its product. You can never use qualpex on the flow & return right at gas or oil boiler either.

You're probably right

The boiler is more obvious