There are 2 kinds of instant water heater built-in pumps, AC Booster Pump and DC Silent Pump.

Differences between AC Booster Pump vs DC Silent Pump are:
- Pump speed | AC is stronger than DC
- Noise Level | DC is silent while AC is noisier
- Energy Efficiency | DC is more energy efficient than AC
- Warranty | DC usually has longer warranty than AC
- Price Point | Instant water heater with AC is usually cheaper than DC

Hence if u want stronger water flow, go for AC Booster Pump, but take note of its disadvantages as well. I suggest u to purchase the brand that created the AC Booster Pump, CENTON. My friend is using CENTON Vintage (I think that's the model) with matte black color, quite nice. CENTON brand can easily get from Shopee / Lazada.

Do note instant water heater built-in pumps are sufficient for showers, but u cannot expect hotel-like water flow. Hotels are using powerful booster pump at the main water supply, with brands like Grundfos, also suitable for landed properties. But make sure don't choose too high-powered ones, your house pipings / joints / faucets / water heaters will leak or burst from overpressure. Also faster water flow = lower heating temperature rise for instant water heater, so u might want to upgrade to a higher kW instant water heater, or get a storage water heater.

I'm located in Selangor ~ seri kembangan, please recommend for me thanks ~ I don't dare to risk drilling into water pipe or crack a tile 😬

Hi all,

Anyone can guide me on instant water heater pump pls.

Compared Joven and Centon as recommended, I'm currently using Joven 880P with AC double ball bearing booster pump. Water pressure is still.. alright, but it is far from satisfaction. Apparently this double ball bearing booster pump can provide 4x stronger water pressure.

So I looked at
Joven SB11p - claiming 4x stronger water pressure
Centon Grande - claiming 4.5x strong water pressure

My concern is, what if I buy only to find that both models give me the same level of water pressure? Can anyone giv suggestions how to get stronger water pressure pls?

p/s: Not looking to install separate water pump after tangki, afraid that old pipes can't handle the pressure.

FYI for these 3 brands CENTON / JOVEN / ALPHA, most of the directors of these 3 companies are related by blood / family members. Hence I am guessing u can expect very similar AC Pumps' performance comparing JOVEN vs CENTON.

If u have used JOVEN's AC Pump before and that is not strong enough for you, than I think most instant water heater's built-in pump won't be strong enough for u (these 3 brands are already the best in instant water heater built-in AC Pumps, and AC Pumps are more powerful than DC Pumps).


Centralized booster pumps like Grundfos is the way to go.

But since u don't wanna get booster pumps, last resort is to get shower handsets with super small diameter nozzles / holes at shower handsets where water comes out from (many China handsets on Shopee / Lazada that claimed these handsets can increase water pressure). Technically it is true, the smaller the nozzles, the higher the water spray's pressure.

But take note that these small nozzles' handsets downside:
1. Blocked Nozzles | Their small nozzles more likely to get stuck / blocked from fine dirt / mineral build-up, so u need to clean it when they are stuck.
2. Painful Jet Spray | Since the nozzles are small, the water jet sprayed out from the nozzles are sharper, which if u have sensitive skin, can be painful during shower.
3. Water Heater Warranty Void | Some water heater brands' warranty will be voided if u use other shower handsets that don't come with the heater. I suspect one reason maybe because of Point 4 below.
4. High Pressure Built-up | These handsets will increased water pressure built-up in the heater, and if over the pressure limit indicated in the heater's specification, might damaged the piping joints or heater tank.

thanks for quick reply!

Sifus any recommendation for Rain shower instant water heaters with DC pump ?

I've seen the toshiba one but I saw that there isn't a control for the pump. correct me if I'm wrong.

*apologize if I'm spamming (posted on 3 water heater LY forums), but quite urgent as I'm gonna start reno and need to decide if I'll ditch heater storage tank and go with instant heater (save money on hot water piping, mixer)

Hi Sifus, need advice please. I have 5 bathrooms upstairs (4 daily use bathroom for parents and children; + 1 guest bathroom). In terms of usage, there’s a high possibility that at least 2-3 persons will bath at the same time and possibly up to 4 pax at the same time

Can I get advise on 3 questions : (assuming no rain shower in any bathrooms)

1. I’m planning to get Joven storage water heater. Would it be better to get :
A) 91L to supply all 4+1 bathrooms
(am concerned that 91L would take too long to heat up and in the event of “malfunction” all bathrooms no hot water and costly to replace vs Option B)

OR

B) 68L to 3 daily usage bathrooms (rooms are next to each other) + 25 or 35L to 2 bathrooms (daily usage bathroom + guest bathroom)

2. Whichever the option, is there anything in particular I need look into in terms of wiring/switches?
Sorry if it’s a noob question, Is it possible to have 5 way switches to control one heater tank (option A – 91L) or 3+2way switches to control 2 tanks (option B 68L + 35L). Ie, each room has their own heater switch and turns on the heater when they need to shower. Any issues if 2 persons turns on the heater switch to the same heater tank?

3. Based on the preferred options, is there a difference to the number and HP of water pumps I need, or I just need 1 as usual, at the main water inlet right after the POE filter? What HP water pump should I get? (I’m presuming I’ll need water pump as I’m installing a storage heater tank, right?)


Thank you very much in advance for all advice

Cheers!

Vern

1. Sizing of WH can base on expected runtime here https://www.aosbath.com/sizing-your-water-heater/

2. Single point of switching recommended. Having many switches will be quite a colossal feat, and is not as per ST guidelines for WH installation.
The first priority is that each unit WH is to be fitted with its own 10mA RCD.

3. Your piping must be able to handle the pressure from the pump output. IIANM it is illegal to pump syabas water direct from the main incomer, your pump if fitted, should only pump from own tangki source.

4. Additional note. For residential homes that don't have constant all hours demand for hot water like hotels...

The built in pump model has no separate button, it uses its own auto flow sensor to operate.

Hi ceo684!

Thank you for the advise.

1. Seems like Joven's capacity recommendation is overzealous



For 50L Joven only recommends 2 person shower vs aosbath 3-4 pax. which to believe?

2. Is the recommendation per the url below safe and legal per ST guidelines? If I were to have only 1 switch, each user have to come out of their rooms to turn on the heater switch to bath and do the same to turn it off. Seems quite inconvenient, and more so, users will forget to turn off as it's not the usual "directly outside the bathroom wall" switch. And if I were to get 5 individual heater storage tanks so that each can have their own switch, better to go with solar heater right?
https://www.electricaltechnology.org/2020/0...r-switches.html

3. Oops, I was not aware the pump should be after tangki, perhaps I mis-read/interpreted.
How do I determine the HP required? And once decided on HP, I'll have to determine the piping required to meet that pressure right?
Is there a specific piping material or size I need to be aware of? eg. PVC 15 mm? 20mm 25 mm? or have to be PPR/buteline/etc (any specific dimensions I need to be aware off)?
My contractor has currently quoted for PVC class 6 for cold water, PPR for hot water

4. Noted with thanks. Am trying to decide between solar heater, instant heater and storage heater tank (for aesthetic purpose vs instant heater - which wifey wants). Cost effectiveness wise, without detailed calculation, I'm quite sure instant heater wins hand down
Already have back up plan to propose to wifey which looks nice and can have rain shower : Toshiba DSK38ES3MB-RS
For solar heater, I'm concerned about the 500kg weight on the 30 year old roofing with wood truss and the maintenance/troubleshooting of any issues vs instant/storage tank and also the upfront price tag is higher (RM1.5k for 91L joven / RM2.4k (RM1.3k JH68 + RM1.1k JH 35) vs RM5k for solar heater)

Cheers

Hi vernee
1.AOS being SG based, may be based on shorter runtime since SG utilities OPEX quite expensive. Joven could be quoting less pax for "hollywood showers" since MY water and electricity is considerably cheaper so people tend to take long shower here.

2. ST main requirement is to be able to isolate WH completely, hence all electric WH need 2 pole switch chopping both live and neutral. It is relatively uncommon to see 2 pole switch also in 2 way (staircase OR mode lighting switch) configuration.

3. Typically pressure rating of downstream fittings will be based on by the bar of the pump. In terms of if shit happens..concealed piping if leak inside wall at the JOINTS will ultimately need hacking. Easier if no tiles. But bathroom any how also will at least have half height tiles.

I imply that most likely you will be going concealed piping, hence in that case buteline will be best idea for the pressurised cold water for less headaches. PVC class 6 or 7 will be able to sustain but the weakest link not the pipe..its still the joints.. which are ALWAYS at higher risk of leaking once pressurised. As PVC regardless class 0 6 7 all still have fundamental weak point of the chloroformed/glued joints.

For the heated unpressurised pipe from storage heater..for the pipes in the air it is wasting heat..this is supposed to be kept warm, sp for rhermal efficiency can use the pool noodle lookalike superlon round tube insulation.. 6 feet only rm2 or so nia. Yes this is the same as aircon insulation.

You must be thinking this girl siao wan..use aircon insulation for heater? If superlon, their datasheet say it can tahan up to 95C IIANM so more than enough temperature safe tolerance. The part buried inside wall wont suffer much heat loss so no need to insulate lah, but if really want also can insulate all the way (though the hacked longkang will need to be slightly larger).

As for backup plan..
Instant heater with DC pump built in typically will work for low pressure condition so you still have enough flowrate to take bath without scorching yourself..but rain shower wise will work lah..just not strong as a proper storage heater and external pump setup. For instant heater w built in pump the default handheld shower head will give good pressure, but adding on rain shower head it will not be same as hotel shower ya.

This post has been edited by ceo684: May 2 2021, 02:23 AM

owh but i did see Alpha and Deka has gauge controller for motor

both are rain showers

hmm

has anyone used the 2 brands above ?

This post has been edited by jarod89: May 2 2021, 09:11 AM

I suggest to go for storage water heater newer enamel-coated tank technology (CENTON, MIDEA, XIAOMI, BEEBEST), rather than the older stainless steel technology (JOVEN, ALPHA, ELTON, PECOL).

Enamel-coated tank are in general (compared to stainless steel tank):
1. Newer technology
2. More leak resistance - 1 welding joints instead of 3
3. On average cheaper - using mild steel with enamel-coating instead of stainless steel, hence cheaper material cost yet better leak resistance


Also, 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. With that reason, I recommend 1 storage water heater for 1 bathroom, unless the bathroom is next to each other.



Most Malaysian brands (CENTON, ALPHA, JOVEN) that comes with built-in pumps has pump control knob to adjust / turn off the pump.

Do note that if u choose an instant water heater that comes with rainshower, the warm water has to travel up the stainless steel pipe to reach to the rainshower head, causing significant heat loss. Hence, it is better to select an instant water heater with higher power rating. If I am not mistaken, ALPHA and DEKA is only 3.6kW, TOSHIBA and MIDEA is 3.8kW. I suggest u to try CENTON, as far as I know all of their rainshower are 4.2kW, should be the highest power rating rainshower model in the market.

There are plenty of brands out there for instant water heaters with good pump.
I have been using non-famous Sharp brand for almost 8 years without any issues. Most brands are with warranty, just go do some survey.
Get the one that suits your need and budget.

so far in malaysia market only Sharp and Rheem using RCD , while others using ELB ?

It is still recommended to cut off the whole supply line into the bathroom, i.e. using DB-box-mounted 10mA RCD (or RCBO).

Just fix a RCB. Usually new housing wiring, they already install RCB for heaters in your DB.
If you dont have it, its recommended that you fit that in your DB

If your is new house, you wont have pressure issue.. Get Pansonic non-pump model ... RM300 Max.. Save your money lol...

Wah 10 yrs ago punya question
I think he or she already bought a WH already

Yup its not terribly expensive but it is a very worthwhile investmemt aka one time off life insuramce. It is also a mandatory requirement under the law to have a 10mA RCD for WH (wet floor appliance).

This post has been edited by ceo684: May 3 2021, 11:11 PM

Mandatory for new housings. Old ones still using without RCB, only normal CB.
But main RCCB is already common i would say. (but 30mA is not really suitable to safe life though)