oil central heating

[ezzzekiel]

saw a oil tank in garden today with an earth rod connected to it, water bonded inside and thinking about it this must be wrong, the pipes from the oil tank will be introducing earth at a different potential to the pipework inside the building giving a difference in potential between the two any thoughts on it?

 

[oldtimer]

Emmm could the oil tank be rodded for static and the supply pipe to the property could this be plastic ?

 

[ezzzekiel]

all copper pipework

 

[D80]

http://www.electriciansforums.net/e...rht-gas-meter-using-earth-rod.html#post487575

Probably this plumber that did it!

 

[ezzzekiel]

Whole estate appears to be the same, oil services should be bonded from met but it looks like an awkward run so I think someone decided to rod at the tank and cross bond the pipes just before they enter the building, can't get head around it?

 

[oldtimer]

How old are these tanks as you say all copper so I take it they are more than 15-20 years old

 

[ezzzekiel]

Sorry tanks are plastic just pipe work leaving them and entering the property to boiler are copper.
By adding the rod the heating pipes will be held at a different potential to any other services within the property or am I missing something?
Or introducing a different earth potential

 

[D80]

Sounds like a right bodge up. Probably would find there is continuity from MET to the pipework as it would get it through the likes of the boiler and perhaps the immersion but it doesn't seem to be any bonding to the oil line. The earth rod makes things worse rather than better

 

[jeremy]

I used to be Oftec registered, incoming pipework must be bonded as any other incoming metal service pipework, though I saw very few that were.

 

[oldtimer]

Sorry tanks are plastic just pipe work leaving them and entering the property to boiler are copper.
By adding the rod the heating pipes will be held at a different potential to any other services within the property or am I missing something?
Or introducing a different earth potential

Ok a plastic tank but a metal pipe why not plastic and why not ditch the rod as the pipe is earthed as it enters the property like you do with the external services such as water & gas or have I got this wrong

 

[ezzzekiel]

Underground metal pipe introducing earth potential into property but not bonded to met, my thinking that by adding the rod and not bonding back to met is only making matters worse

Can understand the rod to ensure earth connection but without bonding back to met you are introducing a dangerous difference in potential into property.

 

[oldtimer]

So as I said ditch the rod and bond the pipe as it enters the house same as water & gas that may be metal in the house and up to the boundary wall and then it changes to plastic as they hit the pavement and all 3 services are the same.

Mind just to add I have seen a gas pipe on the pavement supplying house that are raised higher than the pavement with a 25mm green / yellow cable terminated to it so when you think of it they are doing the same as the oil supply because I take the gas board are bonding their pipes to a rod.

 

[ezzzekiel]

Need to speak to housing association there quite a few will need to be done, just wanting to get facts straight before i approach them

 

[Guitarist]

Regs state to bond pipe inside property from MET. Agree with oldtimer here

 

[ezzzekiel]

Spoken with them and apparently they were aware of the situation and were advised that installing a Rod was adequate by nic helpline, don't quite believe it though

 

[D80]

Unless it was the receptionist I doubt they got that solution from NIC!

 

[Guitarist]

A lot of receptionists do consider themselves knowledgeable.... Take some of them at the Doctors surgery.

 

[telectrix]

nothing wrong with the rod as long as the pipe is bonded to the MET inside the property.

 

[ezzzekiel]

Yeah which it isnt so would imagine the rod alone is just making matters worse but out of my hands now