As per title, been using this for more than 10 years in my house, old house layout where the switch for heater is in my room

Recently it burnt, so it concerned me as is it ok to use 13a for this water heater, or it's best to change to the 20a on off switch, or the 15a round plug and socket? Thanks!

Not just the plug and sockets. Have to consider the wire as well.

No. Recently my 13A plug used on my kettle melted due to poor contact after few years using. The kettle is rated 2200w. The plug head can be felt quite warm during use when i got it for new, so i suspect the copper has oxidized and having bad contact later throughout the years. Better to be safe than sorry.

Water heater cannot use plug. It will melt.

Opt for 4mm wires and connect directly to the MCB.

I have seen cases people using 15A plug and it melted the socket too.

So, don't play2.

will melt... dangerous

20A

No. Singapore couple got electroluted by using this.

definitely is a no

For Your Information.
https://www.channelnewsasia.com/singapore/e...d-wires-2551426

Thanks for all the replies, this is how the whole thing looks like, so whats my best next step? Consult an electrician? Or change the plug socket to 20a?

U cannot just change the socket to 20A. The wires must be 4mm too.

The power socket wire is 2.5mm only. Good for 13A max.

Better to pull 4mm wires from the DB straight to the heater. On the DB, use either 20A or 25A MCB. No need for plugs or sockets in between.

Much safer and reliable.

WH will require minimum 4 sq mm cable with RCCB 10ma protection - this is Suruhanjaya Tenaga rule!

Your water heater if on at full blast (max temperature) will melt the cable and the 13A socket plug.

If you insist to use back the same wire you must minimally install the 10ma RCCB and make sure your RCCB is 16A at maximum otherwise your cable will melt and catch fire - the cons is you should not on your WH at max temperature because your breaker will trip to protect your wire from overheating.

Still 13A socket point should not be used here, go buy the one specialized for WH. This is a matter of life and death though have fun arguing with some half-past-six electricians that will suggest with you to go with 100mA RCCB or even 300mA to prevent tripping - 30mA may be the best advice they could give HOWEVER 10mA is A MUST by ST rule!

Do not forget - Insurance might choose not to compensate if they find that the accidents/fire was caused by wiring setup that did not follow the right specification!

Yes & no.

Very long time ago, when we wanted to install a water heater, the electrician tap from 1 of the lesser use power socket (13A) at the room next door. Controlled by a 20A switch.

So far 28 years, I'm still surviving.

thanks for all the kind info, it kinda complicated to me, so i guess it best to leave it to the professional


this house is more than 20 years old, and im in the same boat as you

Good to hear that!

1 month ago 300 Mat Rempits illegally gathered in huge group and raced in Penang but just less than 2% died - supposed rempiting is 98% safe. 😂

Yes, just make sure the professional is a real professional with licensed and advise according to guideline.

Life is cheap anyway and you are not alone actually, as I can see many houses are not setup according to specs and regulation.

The othet suggestion I have which are cheaper and do not require major rework would be changing the socket to the WH type 15A at least, and before the switch just install a dedicated RCCB 10ma before your 20A switch which should give you a good protection already.

The old Thai houses wired the WH using a single RCCB usually planted next to or on top of the WH.

do u mean this socket? i saw yr comment stated 30ma, will 10ma ok for it?
for the RCCB, should i get the 2pole or the 4pole?

I assumed steps as below
attached a RCCB before the socket
change the 13a socket and plug to a 20a switch/ 15a socket and plug?



This post has been edited by hottemper: Aug 23 2022, 09:09 PM

Yeap - if you can invest in this product is even better - to replace the 15A plug.



This post has been edited by davidlow7: Aug 24 2022, 12:02 AM

The rccb installed at 1st or 2nd place ya? Thanks bro

You are welcome.

It doesn't matter... but I would recommend the 1st place just before the switch (outside your bathroom with the on-off switch together) - it would work to track the current movement along the circuits already. I don't recommend putting it in the wet area (inside bathroom especially) so I would not recommend option 2 which many would usually put beside it. It is not an IP65 66 or whatever IP rated device.

Cannot get job if use proper specs. Total bill few hundreds for barang alone, customers think I'm ripping them off.

Because too many RM80 installer on FB. People expect cheap. Using proper materials not part of the equation. Else I'd just ask customer you go buy the materials as per shopping list, then I come. Then they will appreciate that the components cost good money.

The switch is in my room, so i plan to replace the switch to 20a and add on the rccb 10ma, is that ok?

It's too much of hassle if to add another socket outside the bathroom and the wiring is hidden above the ceiling

Nowdays heater are 3800W with pump - 13a surely will burn after sometime. I usually use 20-25a Aircond switch and directly wire the heater to this plug instead of using a normal wall plug. Minimum wires size 2.5mm but 4mm ideal.

True.
I spec everything for my house and just ask them to name the price - things that I do not agree I will source my own part. For example the SPD RM500 ABB, he charged me rm1000+ for same thing. Not sure if his supplier gave him the correct price though.

Usually I am still okay if price is just the issue so at least we can directly go into negotiating - but what annoys me the most is the issue with their knowledge .. saying no such thing of 10ma for water heater and saying RCBO does not exist in Malaysia.


You can but if can please ensure it is protected from water splash - buy a transparent cover probably that covers it well. Make a habit to test it monthly for safety purpose.

If your setup is 2.5mm and using on good brand like MEGA or Caramay is okay - but anyway if not, and become too much of a hassle to change then you must make sure your setup along the circuit must be correct and right sized - 16A/20A MCB max.... - 2.5mm wire must follow the 2.5mm way of setup then would be good.

This post has been edited by davidlow7: Aug 25 2022, 10:35 AM

The instant water heater is normally at 3.3kW to 3.6kW power rating. So, current flow would be

3600/250 = 14A (worse case). Even 3300/250 = 13.2 A

The current 13A socket is not suitable. It still works for long time because there is buffer to its rating normally not specified. Therefore it works near its max rating most of the time. The rating is related to contact resistance between socket and plug. So, if the current is high, the heat will also generated thus weaken the copper property over time. The clamping contact worsen over time until the point it get burnt.

The best would be using higher rated socket and the best available is 15A socket. I've been using for more than 15 years with no burning sign and my heater is 3.3kW rated. As for the wire from the socket to the heater, the 2.5mm² is fine. It should be able to carry even 25A (or at worse 20A) at 60ºC ambient temperature, according to calculator I have here. Anyway, it is short cable.

The water heater has internal RCCB or ELCB, but test it regularly to ensure functionality. Adding 10mA RCCB provides redundancy just in case the internal one fail. Well, I don;t have one also

No wonder i saw a test button and reset button on the side of the heater, that make sense now 🤣

On 2nd thought, since you have base box where you mounted your current socket, why not just straight away use 20A switch and feed wire directly to the switch. Just need to make hole on the base. This way you have double pole switch as isolation and no pin contact issue over time.

The water heater built-in ELCB does not to protect human, it is only for the equipment. This had been highlighted numerously by our sifu @ceo684 which is correct so you are left with only the main RCCB to protect you in case of any leakage outside the water heater ..and usually the main RCCB at 100mA would not be able to protect you from death... at 30mA you would stand a chance to survive but not one without severe pain and injuriy to your body.

This is also shared by Showertec
This post has been edited by davidlow7: Aug 25 2022, 11:16 AM

Your water heater is rated at 15A while your plug is 13A, obviously it overloads it.

If follow ST guidelines, it has to be directly connected or using a proper certified connector and 4 sqmm cable.

In practice 2.5 sqmm cable works fine if your water heater does not exceed 20A.

Just take note newer water heaters today may consume beyond 15A, hence, even using 15A plug/socket (The round pins) is not advisable.

That's what I'm planning to do, already bought the 20a switch, just waiting to buy the rccb

I'll follow yr advise to add on a 10ma rccb, thanks again sifu, one question, since it have 2 pole for L n N, how about the Earth wire? Direct connect E to E?

There should be an earth wire that is connected directly to your DB Earth Busbar - so there will be 2 options depending on your setup.

Setup 1:
if you are using a 20A switch without another 3pin(round)socket --> then this earth wire will connect to your WH unit directly.

Setup 2:
If you are using a 20A switch + the 3pin (round) socket then this earth wire from DB will connect to your the socket in "E", while the L+N will come from your 20A switch.

This post has been edited by davidlow7: Aug 25 2022, 11:40 AM

I understand perfectly how ELCB and RCCB work. Why the big name in water heater manufacturer still use ELCB not RCCB? ST should make it mandatory to use RCCB for water heater, don't they?

How did people get electrocuted in cases of water heater? The casing is plastic and the hose is silicone rubber. Is it because the water heater uses ELCB not RCCB?

I can understand the point you are trying to make. especially for a more advanced user like yourself, but in reality things are always never going to be straight forward that's why I would advised against sending a message that the ELCB in each WH unit are safe and designed to protect human like exactly in RCCB.

Ability to understand the technicality of everything would help yourself in making an informed decision, but when it goes to the MASS then it is about making sure it becomes practical for people to understand in the most simplest manner possible.

You would never know what are inside certain manufacturers' units and the timeline that bought also came with it, and also the customization by users that would happen over time, such as the use of stainless steel rain shower to replace the hose set. Some people would be using very old units that might have different components in it - the truth is no one can confirms unless a test on each model would be examined - which is of course not possible.

What we know is - For sure following the setup for a dedicated RCCB 10ma would eliminate the uncertainties around.

This post has been edited by davidlow7: Aug 25 2022, 12:12 PM

The main problem with ELCB is more into the functionality of Ground wiring which maybe overlooked. The L and N wire if no connection the user will know immediately since device will not operate but for E failure no one will notice. This will not trigger ELCB in case the E circuit failed.

The new device that is more advance than the RCCB is GFCI. This will performs what RCCB does and also sense short between N and E. My company is producing this for a Europe customer.

RCCB and ELCB cost difference a lot. It may cost more than half to 3/4 of a RM200 water heater.
Since the onus is on the user/installation and not mandated (on the mfg of WH).. don't put in better.
After all most consumer only want cheap like a purchasing dept.
You give them good, not that they appreciate (they think we trying to rip em off); not many consumer will consider the quality of work and what they're missing. Only those in the line will be scared (the thing about people dont know what they dont know)..that's why I run my own home DB setup as stringent as possible. Nothing above 30mA on mains and each WH has a 10mA RCD.

ELCB covers connectivity to ground check.
But ELCB is not a replacement for RCCB.
ELCB if not mistaken is a mandatory item in WH that's why they all come with ELCB LED.
There's also AFCI too

Well, many electrical contractors charge too much but using low quality material. Most likely it is because they need to pay workers salary all year round and projects are not continuous all year long. For that reason, I also prefer DIY

I'm not sure about the price because I'm not in this business line. However, if you talk about the manufacturing cost, ELCB is more expensive to produce compare to RCCB but the RCCB perform better than ELCB.

I guess the main reason for ELCB in appliances is detect faulty appliances

Also boils down to where it's made and currency exchange.
ABB/Hager 10mA made in Italy or France easily RM150-160/ea
Cheaper one local made or Schneider around RM100
Cheapest one from PRC around 60 bucks IIRC..
but u wanna save money on the "safety belt" device meh? Especially its "one-off payment life insurance" as compared to whatever insurance every year pay a lot.. this one pay once covered for 20-30 years.


I also DIY because in that sense I know everything is fastened properly and according to spec or even some of the time, exceed spec (especially for short runs).. cable so cheap even for 4mm loose cut.. it won't break the bank. Its about not having to deal with melted wires or risk of house catching fire
For time saving and avoid breathing in plaster ceiling dust I also retrofit wago connectors for those LED downlights.. fiddling with screw connector is waste of my time when i can just clip unclip.

Hard to find clients that will insist to do it properly up to spec (safety is 1st priority) and don't mind paying (reasonable amounts).

This post has been edited by ceo684: Aug 25 2022, 06:30 PM

SG and Msia installations have this same issue of not-up-to-code old installations.

However, there isn't much awareness on retrofitting with 10mA per water heater OR to get the highest sensitivity mains RCD (30mA whole house) in MY.

In SG it is pretty common to see new installations with 30mA whole house RCD everywhere.
10mA for water heater still a question mark in older HDB. Not all have it retrofitted.

This brings up another can of worms - before renting a place, also check the DB box that it's safe to use.

This just popped into my mind this afternoon thinking about those homestay people are going to rent for holiday! Especially in places like Cameron Highland where WH is a must!

Products made in Europe (if it really is) are expensive because of manufacturing cost there. Even when there are similar product from China, they would buy Made in Europe. Nowadays due to component shortages, many Western product s are also using components from China. This is very common now. Those US companies producing their products in China is shifting to Malaysia too. Well, labor in China nowadays are comparable to Malaysia, I'd say, but other cost is higher because components are still from somewhere else.

Many Europe companies are assembling their product in Europe but but parts/modules from Malaysia too. Component from China are also used for their low cost. The CE certification is not like UL in the US. It is the manufacturer that declare and responsible to meet the CE requirement. It is not tested by lab in countries that are importing the products or at least CE certified lab.

The branded product is also expensive because the insurance they paid to protect themselves against any possible lawsuits too . Western manufacturing agreement is a stack of papers while China only need 1 piece of paper. This was true story from my American ex-boss. My work now is estimating cost to produce a product based on BOM list and drawings provided by possible customers and the selling price difference would surprised most people.

Tumpang question since same power rating 3300w.
Is the below safe?


Attached thumbnail(s)

2mm cable? Not 2.5mmsq for the in-wall concealed cable?

Its OK but you might consider using a CEE plug instead of DP switch (so u can disconnect the oven)

For a 3300w power-rated oven, 1.5 sq mm cable is questionable by a mile!

Secondly, I will not use a 2.5 sq mm wire for a power-hungry appliances like oven, I would go for 4mm as you are going to run your oven for a long duration. You are probably testing its limit - a water heater at around 1A to 2A higher usually runs at a much shorter duration is already advisable to go with 4 sq mm wire. Regardless of the wire size, you need to invest in a better quality wire so it can lasts you long - having SIRIM should be the bare minimum

This post has been edited by davidlow7: Aug 26 2022, 09:51 AM

find technician to do dont pandai pandai do things like this... especially shower one.... u can get fry.

My bad. Yes 2.5mm but non Sirim cable installed by contractor

Got some champion use uncertified wire before.
Those that scared to show marked cables to customer are probably suspect.
Especially those using nonstandard tomfoolery calculation 40x0.193 or 40x0.076 type cables are suspect. Because our usual ST spec is 1.5 2.5 4.0mm any funky spec of wires are deemed as suspicious already.

Cost cutting. The minimum spec should be
stiff cable (MS 2112-3) Caramay, Mega Kabel, TONN, or those MCMA cartel
or flexicord (2112-5) Fajar Cable.

Copper price more or less is like that one. Cheap stocks aren't copper.

Using non-sirim product is against the law - you can try raise a complaint to ST if you want but make sure you do your homework and have the necessary documents/information - and also if you think it is worth to go through the "process". It is completely up to you... that's why there is always a phrase of "prevention is better than cure".

Using a non Sirim cable you would expect the cable quality is at least 30% bad (just cincai plucking from the air, but who knows may even be worst). There are videos in YouTube which show you in true practical test - just search it.


Sad to say this is the Malaysia "norm".

Judging by my own experience going to 10 electrical shops giving me bullshit theory (RCBO no such thing, 30mA water heater, 100ma for socket etc) - I would say that this is so normal when wireman decide to also follow the "norm", partly also driven by customers who only wanted cheap.

This. Doesn’t look like got SIRIM

This post has been edited by JasonTheGreat: Aug 26 2022, 02:51 PM


Attached thumbnail(s)

that one tipu cable. If u see the cable insulation there's nothing printed on it right? Or just PVC auto control cable without mfg name.
Clear violation of standards if used in residential 230V but they label as PVC auto control cable

Auto control cable is safe for low voltage 12V/24V in auto(mobile) use or control circuit.
It may not have enough insulation resistance for 230V or 415V.
Insides also likely to be recycled copper or not pure copper.

Fresh copper very pliable and can be twisted without breaking apart on the first time. Compare Caramay/Mega Kabel with any of the PVC auto crap
Price-wise also should hint something is fishy no?

Actual price for 2.5mm still >100, the 90 one is old price clearance stock
At 55 bucks its not like they got the copper stock half price...

This post has been edited by ceo684: Aug 27 2022, 01:37 PM


Attached thumbnail(s)

Here is a snapshot from Suruhanjaya Tenaga's Water Heater Installation Guideline. Not just uncertified technicians, but even many developers are still providing new properties with 3-pin socket in the bathroom, which is very irresponsible. Let's remind one another to STOP using 3-pin plugs for water heaters, and connect the water heater directly to the main power supply (with the correct cable size depending on the water heater's power rating, refer to the next screenshot below).



If you are worry that removing the 3-pin socket will leave a hole in your bathroom wall, you can use a water heater connector to directly replace the 3-pin socket using the same junction box, as suggested by davidlow7 below, such as SIRIM / Suruhanjaya Tenaga certified water heater connector brands like STEC and CENTON. Here is one example from Shopee.


Use this table below to determine the cable size / switch you should be using based on the power rating of your water heater, as recommended by Suruhanjaya Tenaga.



This post has been edited by Selene Yeo: Aug 21 2023, 09:45 PM

Thank you sifus and gurus, now i can bath safer

Everything is working well, rccb, 20a, water heater is all good

What need to do next? Test it every month?



I have another question regarding ceiling led lamp, shld i open a new topic or just post here?

As long as it is a 10ma maximum sensitivity that is a good one.

Suggest to create a new thread for a new topic, but you might want to do a search if there is already an existing thread about the topic which you can leverage on.