My upstairs DB doesn't have slot for MCB + RCCB, so I got the electrician to install RCBO for my storage heater. As the existing heater circuit wiring is 2.5mm², I had to insist on a *20A* 10mA RCBO. Unfortunately ABB/Hager doesn't have such RCBO so I chose Schneider 20A 10mA.

Should I upgrade the DB and replace the Schneider rcbo with MCB + ABB RCCB?

Apart from the brand thing, the layman in me thinks the compact 2-in-1 rcbo is not as reliable as a dedicated RCCD that by itself occupies 2 slots in DB. Am I overthinking?

TBH, since its not the main DB & if its plastic box, it's not really that expensive to replace to a bigger DB box.

The only nitpicking part is whether said RCBO's Residual current tripping technology is VI (voltage independent) or VD (voltage dependent) type

Oh my....new thing for me to research

Thanks.

None of the RCBO (with width of 1P MCB) in our market is of VI type. All the cheaper ones is VD and the more expensive one is VD with FE. Most of 2P RCCB in our market is VI type (less prone damaged by surge than RCBO) with exception of old or cheapo obscure brand (that you only see used by cheapo developer). VD type will not function if floating neutral (loss of neutral before RCD), which is why the more expensive RCBO is VD with FE.

This post has been edited by jio: Sep 20 2023, 06:50 PM

Thanks for the response.
This is actually for new installation

Hi, may I know:
1) when damaged by surge, does the rcbo trip and cannot be reset (fail safe), or it won't trip at overload or current leakage > sensitive setting?

2) if there's floating neutral, what is the definition of "will not function" in the case of VD type of RCBO? Does it fail safe or won't trip when needed?

Hi all
For Storage Type Heaters mounted using a bracket/frame on a vertical wall - do you check whats the maximum load that the wall can

Typically the tanks are 30kg upwards (weight when full), would appreciate some rules of thumb here please

1. The internal circuit for the RCD function will stop working. If that circuit ended up having shorts it may pop when you switch it back on. If you have lightings and electronics stop working after lightning storm, I would suggest you test all the RCDs as well.

2. VD type RCDs require sufficient voltage between L & N in order to work. In fact it will draw a couple mA current when switched on even without load. Floating neutral in single phase, there isn't sufficient voltage between L & N so VD RCDs won't work. In 3 phase it may ended up being overvoltage, VD RCD may trip or stop working temporarily due to overvoltage protection or pop due to lack/failure of overvoltage protection.

Thank you for your reply. Can I assume that in a case of defects in both cases above, it causes fail safe protection, which means power supply to the circuit will be cut off even if the rcbo doesn't trip?

The load divide by 4 leg anchor to the wall. 30kg/4=7.5kg load per leg.

A 4mm wall plug load about 20kg.

That's more than enough.

No, there is no fail safe protection and the power to the circuit won't cut off if the RCBO doesn't trip unless the breaker upstream tripped. The overload/overcurrent protection of the RCBO might still work if it is not damaged by the blown RCD circuit (failed RCD frequently still continue being used by the owner not aware or care enough to test it) , but don't take risk. VD with FE will still work without neutral as it will use the earth as fallback. VI type will still work without neutral as it is powered by the CT secondary winding, even if it less prone to surge damage it could still be damaged.

For water heater it is less of a risk as it rely on control circuit (which will have some sort of under/overvoltage protection) and power relays to turn on the high current circuit. It is when RCBO used with other circuit (especially socket outlets) in wet areas that VD type is not safe during loss of neutral.

This series got pump? If install for condo unit, usually need pump?

This post has been edited by coolguy99: Oct 9 2023, 11:36 AM

No pump. Here's the link: Shopee / Lazada

Condo on average has higher water pressure / flow compared to landed. If you are currently satisfied with your condo's bathroom's water pressure / flow, then u do not need to have an instant water heater with built-in pump.

Hi, today got technician uncle to install newly bought joven sc33. After installation push test elcb button but the reset level not tripping down. Should I call Joven tomorrow before I use it?

Hi folks, I'm considering to install a storage water heater for the 4 showers (3 upstairs+1 downstairs, priority are the upstairs ones, downstairs is nice to have if cost is not too crazy) in our newly completed home. The thing is, the house does not come with hot+cold plumbing.

Questions:
1) Not including the cost of the heater and mixers, how extensive/expensive (ballpark) would the works be to have the piping installed? (the 4 showers highlighted in yellow, and approx location of the tank in the roof in red)
2) Any suggestions for a reputable plumber that can take this on (Kajang area)?
3) Any suggestions for a reasonably priced heater that would fit our application?



This post has been edited by NIGAMAJIGA: Nov 22 2023, 11:15 AM

For the pipings and connections costs, it will be better to get a plumber over to inspect and provide a better quotation for you. Don't forget the cost to redo the plaster ceiling if u don't have a manhole sufficient enough for the installation to take place.


For storage water heater brand to get, I suggest CENTON - so far the highest quantities of storage water heaters sold on Shopee, and the highest numbers of 5-star reviews too. Link here | Shopee / Lazada


Currently there are 2 types of storage water heater tank technology in the market,
a. Enamel-coated technology - newer technology, better leak resistance, and more economical. CENTON / ALPHA are using this technology.
b. Stainless-steel technology - old technology, more prone to leaking, and more expensive. JOVEN / ELTON / PECOL are using this technology.


As for which storage water heater capacities to get, do remember the further away the water output is from the heater, the longer distance the hot water has to travel, causing a lot of heat loss (and additional risk to those below the hot water pipings in case it leaks). With that reason, I recommend 1 storage water heater for 1 bathroom, unless the bathroom is next to each other. 30L / 50L is enough for 2 person to shower back to back, or 70L / 90L if that bathroom has a bathtub.

If in doubt, get the higher capacity ones.

ya i got the same problem. installed 2 units, 1 is ok another 1 got the same problem as yours. changed the front cover between the 2 units, still the same unit having this problem. but if i pressed the elcb without the cover, then it's working. so i think it's a design fault as the gap between the push button of the front cover and the elcb base it too far away.

have you called them? i haven't move in yet so will only call after that.

dah call and joven tech came and fixed that

ps: my home is quite near joven hq hehehe (shah alam kemuning area)

ok did they changed any parts?

also only weekdays or weekends also can?

thanks

just tried to bend the button level only. maybe need some specialist to do during installation if due to button level problem

cause the tech did within weekdays, idk about weekends tho