4.5kw water heater On 13A spur.

[Zdb]

Got a 4.5kw water heater that comes with a 1.5mm2 flex from the manufacturer that looks like its meant to be wired into a 20A DO switch. My question is, isn't the size borderline as 4.5kw = 19+ amps?

Thanks

Edited from 13A

 

[snowhead]

19 + amps isn't borderline.

Where/ how does it suggest a 13a FCU is to be used?

 

[Zdb]

I meant 20A as in DP switch. So the 1.5mm is fine? I thought if the manufacturer supplied it it must be ok but thought I would double check on here.

 

[westward10]

What type of cable is it.

 

[Ian1981]

Usually standard flex 1.5mm 3 core is rated at 16amps.

 

[Octopus]

I would probably put a 45 dp switch on the outlet......this does have a dedicated circuit?

 

[Dave OCD]

OP - are you certain that the flex isn't 2.5 ?

 

[Zdb]

I haven't actually been to the job yet just spoke to a chap on site. I will know more on Monday but he did say 1.5mm

 

[Andy-1960]

You will need to remove the 13A fuse from the FCU and replace it with a 6" nail!!

 

[Dave OCD]

You will need to remove the 13A fuse from the FCU and replace it with a 6" nail!!

That is ridiculous and extremely silly from a 'professional' - obviously the nail would have to be 1" or it wouldn't fit !!

 

[Ian1981]

That is ridiculous and extremely silly from a 'professional' - obviously the nail would have to be 1" or it wouldn't fit !!

I've got a good selection of fuse sizes that may meet your requirements

 

[Dave OCD]

I like the 16 amp.

 

[Andy-1960]

That is ridiculous and extremely silly from a 'professional' - obviously the nail would have to be 1" or it wouldn't fit !!

I know... sorry!! It was for guidance only!

 

[freddo]

That is ridiculous and extremely silly from a 'professional' - obviously the nail would have to be 1" or it wouldn't fit !!

Perhaps he meant M6 not 6"!

 

[Dave OCD]

Terrifying !

 

[freddo]

Terrifying !

How else would I get 25A through that 0.75 flex?!

 

[freddo]

*spoiler alert*
After about 20 minutes at 25A, the flex starts to stick to the carpet.

 

[davesparks]

Most appliances still have their power ratings quoted at 240V not 230V, if this is the case here it will be 18.75A which is fine for a 20A supply. The power at 230V will be less.

 

[freddo]

I passed a direct cylinder at a salon recently, it has 3 4.5KW elements in it, each has it's own 20A supply.

 

[delano]

I meant 20A as in DP switch. So the 1.5mm is fine? I thought if the manufacturer supplied it it must be ok but thought I would double check on here.

It should be a 2.5 cable with a 20 amp switch isolator.