should i use 20A or 15A power point for aircond and water heater?

my contractor said 15A should be enough but nowdays i see alot of people use 20A?

any downside if i ask the contractor to use 20A?

my water heater should be 15A (3600kw/240V)

15 or 20 both ok.

more important is the elcb=10ma

where can I check the elcb? is it the built in self testing in the instant water heater? air cond where do i check? or at DB?

This post has been edited by forks: Mar 24 2016, 03:09 PM

15A is enough

13A the best

Not enough for instant water heater.

Instant water heater can use up to 3600watt, our supply is 230v, at max we will draw ~15.7amps

Best to use 20A for water heater, AC still ok to use 15Amp if HP <= 3HP

Be safe, go for 20A. are you doing new wiring for it?

noted thanks

yes doing new wiring

dont waste money on 20a for aircon la.. wiring men wan untung only.

go check the watt of yourappliances then divide by 220v to get your amp.

only water heater and build in oven need that

why some people say 220v, some 230v and some 240v?

220v to be safe..

230v is base, tolerance if not mistaken is now +10% to -6%, so all incoming need to handle the given voltage and tolerance. Safety need to take account worse scenario when current are higher (if supply voltage fall to lower tolerance voltage)

Check tnb website if not sure.

When buying appliances, always check the typical current draw during normal operation. Do we need high powered water heater for shower? Nope, we won't. Even if yes, can we be sure that wireman will using rated wire for this? Again nope.
So always get appliances that requires 13A only.

Some appliances need more than this.

Yup, Eg like Big Oven, Ceramic / jot plate stove.

Use KW/V then you will know how many amp you need

20A more for oven or items which generate a lot of heat...
Also it is the best not to share the power point.

Let said you have a water heater which require 15amp, dont share the wiring or add extension wire to it.
It will melt the plug. (example kettle 5amp + fridge 4amp + toaster 4 amp) one power point if you add mini fridge 3 amp sure will melts all plugs


Usually 15amp is direct current. normal plug is 13amp only.



This post has been edited by ma3da: Mar 28 2016, 02:31 PM

if just to be safe, can we opt for the higher Ampere let say 32A or 20A? there will be no effect on TNB bill right?

you got to check your DB. if you DB only has 60amp incoming you already used half of it.

a 20amp needs a 20amp mcb. beside that 32a and 20a plug is different from 13amp plug.
the thickness of wire also different

The best is don't use plug for high Amp. Like heater, induction.

Plug have some loose connection contact and will overheat in long run.

Direct proper joint with terminal socket will give far safer contact for high amp equipment.

15A or 20A need to pull the wiring from DB right?

not just looping like 13A

Interested to know this as well.

Hi. My oven say it’s 3300W but the manual say 16A.

I have installed 15A socket but it’s 1m too short to connect to the oven.

I’m considering 2 options
1) Connect the oven to a thick extension cable and connect to the 15A point.
2) Connect the oven to a thick extension cable and solder the cable to the 15A point (removed socket)

Which options is the best and any better suggestion?
Not sure if I can remove the cable from the oven and replaced with a longer one.
Thanks

This post has been edited by JasonTheGreat: Feb 27 2022, 05:27 AM


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Replace the whole cable would be safer.

I not sure how the solder join intend to join. But if just solder without secure the wire join, it will be dangerous.

By constant load.. 3300/230V = 14.34A, its quite close to redline, can be done BUT must use proper equipment.
Suggest to use only a metal clad MK 15A socket with MK 515 Bakelite plug top, and make the heavy duty extension from 4mm² Fajar cable. Anything smaller than your pinky finger-sized cable will be a fire risk.

The question is how did the oven come from factory?
With 15A plug or bare wire only?
if bare wire only it supposed to be a permanent installation item.

Also, please note that round pin 15A plug is UNFUSED.

Water heater switch is always 20Amps.. the recommended wiring is 6mm2 Cu.

You can't calculate an 240V AC voltage as this the rms voltage, its a sinusoid with 324V peak2peak.. its not like a battery voltage which is DC

You guys should get a proper electrician rather than give out bad advice..

Skimping to use substandard material size and quality will hurt you in the long run..

The recommended wiring is 4 mm² or larger. You do know how wire is selected, right? The criteria of voltage drop across the wire, and also the maximum temperature of the wire, at full load?

Oh, by the way.... here's a 32A water heater switch. I guess they are not always 20A after all...


That's exactly how you calculate power when dealing with a sinusoidal waveform. What exactly do you think Root Mean Square is? It's certainly not the "average" as you have stated in another thread. RMS is the equivalent of the waveform in DC, and is used for all power calculations. You are confusing the peak voltage for the selection of capacitors in the circuit.

You do know there are actual qualified people who know what they are talking about in these forums? The trick is finding which person's advice you should believe, and who are the dunning-kruger poseurs.

Which one are you?

Maybe it will, maybe it won't. I certainly won't skimp and cut corners, but then who am I to judge what other people do within their budget and ability? For example, I would much rather everyone install a cheaper 10 mA RCCB from EPS or Maxguard or Himel, than not install one because they cannot stretch their budget to install a Schneider or ABB one.

Ok.. i had to look up dunning-kruger to confirm your sarcasm so ok..

A few posts in this thread says 13A and 15A is ok ... My point is that 13A/15A socket is wrong for a water heater point..

My meaning between 13A/15A socket and 20A H switch its always the 20A switch.. If you have a 32A WH switch thats ok as well.

And yes also to the 10mA RCD for a water heater point..

My criticism isn't on those who are competent rather to those that are not..

i'd rather err on the safety side than save a few bucks.. no offence..

Edit* On the AC caps selection yes my understanding that's the peak voltage so should apply to the peak instantaneous AC current as well.. my mistake then..

This post has been edited by Richard: Mar 1 2022, 01:20 AM

Please check the context in totality, the question was for an oven, not WH.
15A socket is OK for oven as it is below 15A max current rating. It need to be fitted with appropriate 16A MCB because the socket and plug top for round pins are unfused, regardless whether you use the 15A 3-pin OR the CEE 16A commando plug.

High amp things if want to run close to redline rating, yes its permitted if is still within rated current capacity, but there is a core importance of getting proper heavy duty rated stuff.