With ready power point or need to add power from DB?

In that case not a rocket science..just drill 6 holes and hook up power directly only. As it doesnt involve pulling new wiring its pretty easy..any installer also can.

The connector ensure a neat join safely, especially when the point in the wall is placed high up, like Micheal Jordan height where most ppl here will need a stepstool to turn on the WH..so it allows for the WH to be installed at a more reasonable height and safely.

Note that it is geared towards instant WH, not storage tank WH ya.

2.5mm is not follow ST regulation.

This post has been edited by ceo684: Jan 24 2022, 12:16 PM

That connector, is able to support all sort of instant WH, typically 3.xkW class (15-16A or so) AND 4.8kW class instant heaters (21A nominal).
4mm can do up to 32A.

For your case storage WH
power is small at 3.00kW
and the way storage WH is wired, its not using that connector.

ST regulation for WH require double pole switching (cut both L and N). 13A SSO only cut live hence not suitable. Plug connection also prone to overheat due to loose connections.

It should be a plug top that is heavy duty rated like MK646 or at least a proper plug top like MK650 AND a metal clad MK socket. The way some cheapo plug tops melt by itself even at 1800W due to cut corner construction is just apalling not to mention dangerous hence a fixed installation is recommended. And even a cheapo plug top has SIRIM sticker on it breaker only trip if exceed 20A for long enough time.

Remember Malaysia is Bolehland. C CURVE MCB thermal trip is so slow/ lax it only trips when you're halfway cooking the dish. Overseas B curve is used in SG, AU, UK in residential. B Curve u want to buy locally cannot find one.. need special order from RS or element14

tagging Selene Yeo
If hypothetically I am the mfg for the connector, whole house burn down, the connector did not cause the problem as its far from weakest link, then OK.
Also it doesn't make sense to launch two models one 4mm cable and one 2.5mm cable because the latter is contravening ST guidelines of 4mm. Then later the connector become weakest link then it become a liability issue.

2.5mm in device is designed for its heat output w.r.t enclosure and ambient temp. Its "homologated" across the device model design and if the appliance is catching fire by itself all the time on normal operation it should fail SIRIM immediately. Plus the heater is made as-new-unit so the cables inside have very little wear and tear.

2.5mm in conduit part (your point wiring) is the variable component, your house and my house different. And that is WCS with overfilled conduits, insufficient bend radius, insulation damaged from bad wire pulls and what not, without cooling, and lastly age of wires.. who knows your wiring could be 40 years old or more where red also turn pink on the insulation. Furthermore, likely to be installed by unqualified faux electrician. This is likely to be the more suspect portion IMO.

Water heaters are a generic term for (typically) an electric or gas powered device that heats up water.
For ease of discussion lets just split it to instant WH (hanging on walls) and the storage heater (that tank hidden in ceiling).

This post has been edited by ceo684: Jan 25 2022, 04:24 PM

ST guidelines recommend 4mm to cover the long run from DB box to the heater. Votage drop is a problem because P=VI. I can increase substantially and cause unwanted heating.
This could be a long run if you stay in big house or longhouse.

Whereas inside the WH unit the wires are measured in inches i.e. very short so 2.5mm for that part is OK. It cant make a huge enough voltage drop.


This post has been edited by ceo684: Jan 25 2022, 05:15 PM

If the whole length from DB box to the storage tank is <1m then 4mm it lah since loose cut 4mm mega kabel for 3x 1meter is not expensive at all (RM2.80/m).
Because its not worth the hassle of explaining to insurance adjuster if a fire occur and they are gonna wash hands by saying its not following the electricity regulations 1994.

This post has been edited by ceo684: Jan 25 2022, 08:45 PM

If it cannot reach the heater's terminal block then you either splice it properly (within the heater casing itself, or if it comes out as a socket use the centon connector).

No, if you use proper HOKAH flexihose.
Yes, if u use those china made cheapo chrome with bicycle tube inside. Those bicycle tube material exploded whilst I was watching TV.

The 4mm is worst case scenario as some 3 storey mansions already running close to one roll of wire to reach from DB box at ground level to the far end bathroom. So if those people fitted a 2.5mm connection - and there is a problem with it (V drop or overheat) liability wise the 4mm is not going to be the cause of it as it follow proper regulation.
And, from product perspective a meter of 4mm is not expensive. It eliminate the problem of having two part numbers.
Also, 4mm flexicord has enough safety margin not to overheat. 2.5mm is running close to redline for 4800W heater. That's assuming ALL the strands are intact. If chopped just one strand during stripping it might be redline already.

Position the heater rear casing to fit the wires coming out of the wall.
Connect with appropriate terminal block (yes the Malaysian variety with two screws) of at least 30A rated if want to save the RM10 of 32A Wago 221-412 x qty 3pcs.
https://my.element14.com/wago/221-412/termi...2pos/dp/2534732 these are 32A rated UL listed

Remember to install a proper 10mA RCD. Recommend either ABB or Hager because these are VI type. Anything cheap are all VD type RCD.
You only have one life per human, you are not cats.

This post has been edited by ceo684: Mar 1 2022, 03:41 AM

Most welcome. Its alright to be overspec so you don't need to worry about strands breaking and derating.
Bearing in mind, in-wall conduit there's still a little tolerance of air gaps "like wearing a loose baju kurung - more airy" yet its already derated on calculation.
Flexicord basically all bunched up together in the same PVC sheath "like wearing a sheath dress (body hugging) which is a bit warmer". The air cooling is nonexistent. So by inferring the derating parts, flexicord in installation guidelines are not recommend for permanent installation (but overspec is alright since it won't get warm enough to cause trouble).

Fit a 10mA RCD per water heater (at the DB box).
The why's are here - https://forum.lowyat.net/index.php?showtopi...ost&p=103837393

Also, for the mains RCD (whole house) use a 30mA.

Humans die above 50mA leakage current passing through the water heater.

Hence, 100mA/300mA RCDs are "close one eye" or "close two eyes" = they will kill you before they trip.

Overpriced..for that price bracket no push start.
All are the same.. electric kettles in a plastic box.

Most cost effective is the RM280 Pana Push start model.

Panasonic basic model with push start have lasted us for decades. I even bring over the same unit from my childhood home to its 3rd address

The main cost of the TNB bill comes from heating. Only a very small % comes from the pump.
95% of the 3600W is from heating
maybe 150-250W from the pump

Main consideration should not be electrical savings when comparing pump type (which u won't feel);
the main consideration is the pump noise btwn pump types (DC is quieter)

whole installation illegal.
mains (as single RCD) cannot 100mA. Max 30mA (0.03A)
WH missing any 10mA RCD/RCBO for the WH circuit. Illegal. Can die one. Many ppl die liao. https://www.nst.com.my/news/nation/2020/08/...e-electrocution

Find a way to slot a RCBO in since ur DB box pretty full. Lights can combine since not critical and won't overload.
If more than one water heater suggest get a new DB box. U are missing the most important and most expensive elements.

U will need the CC225B for each water heater
https://www.combielectric.com/circuit-break...b-cc216b-cc225b

Spending thousands on insurance agent premiums on yearly basis but not spending one-off (ok la 30-40 years change) on proper electrical safety?

This post has been edited by ceo684: Aug 11 2022, 10:20 PM

1. Yes. Either Hager France or ABB italy. Schneider is cheaper but there's a long reasoning why its cheap besides made in PRC.
2. Yes. one CC225B per each heater.
the 20A only on overcurrent. does not protect against leakage current (current in and current out must be within 0.01A otherwise trip). Humans die when over 0.05A leak thru the human body so that's why must have sensitive trip devices.

https://shopee.com.my/ABB-F202-25-0.01-ELCB...1856.9133931062

Note this will take up two module additional in the DB box.

You might need DB box upgrade to 32- or 48-way (e.g. https://shopee.com.my/Eaton-Metal-MCB-Distr...1071.5309739454 for metalclad)

-- for other sizes of RCCB can check abb.os their retail pricing is very competitive tbh
e.g. for whole house 30mA
30mA/high amp 63A is cheap for single phase https://shopee.com.my/ABB-RCCB-ELCB-FH202-A...113.11846935209

for 3 phase 30mA/high amp 63A also RM220 terbang one https://shopee.com.my/ABB-RCCB-ELCB-FH204-A...4113.9793514870

Sh*t gets expensive at 3-phase

Get a plumber to ready the water point and "dead cap it" with the 50c stopper.
Then it will behave like any other home installation with ready points, ur electrician (PW1/2 cert min) will be able to kautim.
If you conceal, mark the pipe line with masking tape so to mark as "no drill zone".

This post has been edited by ceo684: Aug 25 2022, 08:22 PM

needs some work to make it safe. currently its a mess with the exposed busbar.

change the 4x MCB away with same brand to maintain same physical height.
loose connections cause fires.
its only 36 or so for 4x MCB and about 10 bucks for half a busbar

also mains RCD [whole hse] if running only one, should be 30mA [0.03A NOT 0.3A] to protect 13A sockets.

This post has been edited by ceo684: Sep 24 2022, 03:01 PM


Attached thumbnail(s)

Panasonic Push-start staple models are pretty good.

Still using National ABJ 2 biji from 1997 at parents' place; and my own place a mix of 10-year old square ABJ model and a newer M series.

All retrofitted with 10mA RCD.

The M series

Water Heater Jet Pump DH-3MP1MW - Panasonic Malaysia https://www.panasonic.com › jet-pump › dh-3mp1

https://www.panasonic.com/my/consumer/home-...mp/dh-3ms1.html

This post has been edited by ceo684: Oct 11 2022, 03:10 PM