EICR on a Sunday

[vxwestie]

Is there a requirement to remove 90% of fittings on an EICR or go into a loft space?

Ive never earnt an extra penny for working on a Sunday either... Lol

 

[sparksburnout]

The job I mentioned above the bloke is some kind of air-con installer and apparently they always use 2.5mm for 3kw loads!

Pedantic as ever Dave eh? I think you will find 2.5 is extremely common for immersion flexes, FFS how much more does it cost to install a cable that is well over capacity for the load rather than one which is only just over. If I came across a plumber who stuck a bit of 1.5 in I would ask why as well.

 

[davesparks]

Pedantic as ever Dave eh? I think you will find 2.5 is extremely common for immersion flexes, FFS how much more does it cost to install a cable that is well over capacity for the load rather than one which is only just over. If I came across a plumber who stuck a bit of 1.5 in I would ask why as well.

Cost is irrelevant. If 2.5mm is squeezed into a terminal designed for a max of 1.5mm then there is a problem.
Do you also install all final circuits in bigger cable for the sake of putting an over capacity cable in?

I installed a ring final in 1.5mm at the weekend as that is what my calculations said would be right, would you have done it in 2.5 and wasted the extra couple of hundred pounds?

 

[sparksburnout]

Cost is irrelevant. If 2.5mm is squeezed into a terminal designed for a max of 1.5mm then there is a problem.
Do you also install all final circuits in bigger cable for the sake of putting an over capacity cable in?

I installed a ring final in 1.5mm at the weekend as that is what my calculations said would be right, would you have done it in 2.5 and wasted the extra couple of hundred pounds?

How many immersion heater heads are designed for 1.5mm? why would you install an RFC in 1.5 was it for a specific application or for general use, RFC's are usually installed in 2.5 as far as I am aware I cant really understand the point you are tying to make??

 

[sparkstu]

Pedantic as ever Dave eh? I think you will find 2.5 is extremely common for immersion flexes, FFS how much more does it cost to install a cable that is well over capacity for the load rather than one which is only just over. If I came across a plumber who stuck a bit of 1.5 in I would ask why as well.

Why would you ask why to a bit of 1.5 butyal? I never find 2.5 it's always been 1.5 and that's all I've ever done for standard immersion heaters why use anything else

 

[sparksburnout]

Why would you ask why to a bit of 1.5 butyal? I never find 2.5 it's always been 1.5 and that's all I've ever done for standard immersion heaters why use anything else

So that you don't find them suffering from overheating and general degrading over time, given the arduous environments they are often in. If you are running them off an FCU then that's a bad idea anyway as the fuse is at its limit and contributing to the overheating. How much more does a bit of 2.5 cost?

 

[sparkstu]

2.5 butyal rated at a higher temp then 1.5? Don't think so! As Dave has already said cost is irrelavant

 

[sparksburnout]

2.5 butyal rated at a higher temp then 1.5? Don't think so! As Dave has already said cost is irrelavant

Who said anything about the temperature rating?? 1.5 is rated at 16A, which, given the conditions it is being used in, is running it close. Have you not come across such cables in a bad state after prolonged use? And what's butyal anyway, it is like butyl?

 

[davesparks]

How many immersion heater heads are designed for 1.5mm? why would you install an RFC in 1.5 was it for a specific application or for general use, RFC's are usually installed in 2.5 as far as I am aware I cant really understand the point you are tying to make??

As far as I know the standard single phase 3kW immersion is designed for 1.5mm fix, and the cable grip certainly ain't big enough for any bigger flex.
I installed in 1.5mm because it was the right size for the job and I don't suffer from the urge to oversize the cables unnecessarily.
RFCs are subject to a minimum cable size of 2.5 for plastic insulated cables and 1.5 for mineral insulated cables though it is usual to install in 4mm single commercially to meet grouping requirements.

 

[davesparks]

Who said anything about the temperature rating?? 1.5 is rated at 16A, which, given the conditions it is being used in, is running it close. Have you not come across such cables in a bad state after prolonged use? And what's butyal anyway, it is like butyl?

You mentioned general overheating and degradation which in my experience is almost always down to the temperature affecting the insulation inside the terminal chamber of the immersion heater. I have never seen a 1.5mm butyl feeding an immersion heater suffer from overheating through overload.
localised heating at the terminations does not necessarily indicate overload or 'running it close', heating through overload is normally visible as a deformation of the insulation and sheath along the length of the cable or localised at bends or other stress points along the run of the cable.

A 3kW 240V immersion heater (2.7kW at 230V) which is the standard these days will draw 12.5A. this is just under 80% of the rated operating current of the cable (16A) I don't see how you can consider that to be running it close? It is only 4/5 of the rated current of the cable!