water heater type question

[KLL]

i have a new water heater, on a for my understanding good electric setup,

but it does some NOT funny things,

- sometimes it does not heat the water

- sometimes it spits hot water and steam

( even the water is NOT open and the heater RED LED is OFF )

there might be the possibility that it happens when a other water outlet is used??

can i get help to find out what type of heater it is? is there a pressure switch in the inlet pipe? or a flow sensor?

maker and model:

Electrolux EWE451BX-DW written on cover ( while some paperwork is for model AX )

http://www.electrolux.co.th/%E0%B8%9C%E0%B8%A5%E0%B8%B4%E0%B8%95%E0%B8%A0%E0%B8%B1%E0%B8%93%E0%B8%91%E0%B9%8C/%E0%B9%80%E0%B8%84%E0%B8%A3%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%87%E0%B8%97%E0%B8%B3%E0%B8%99%E0%B9%89%E0%B8%B3%E0%B8%AD%E0%B8%B8%E0%B9%88%E0%B8%99/%E0%B9%80%E0%B8%84%E0%B8%A3%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%87%E0%B8%97%E0%B8%B3%E0%B8%99%E0%B9%89%E0%B8%B3%E0%B8%AD%E0%B8%B8%E0%B9%88%E0%B8%99/EWE451BX-DW/

buy from

https://www.dohome.co.th/dohome/th//ELECTROLUX/ELECTROLUX-%E0%B9%80%E0%B8%84%E0%B8%A3%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%87%E0%B8%97%E0%B8%B3%E0%B8%99%E0%B9%89%E0%B8%B3%E0%B8%AD%E0%B8%B8%E0%B9%88%E0%B8%99-4500-%E0%B8%A7%E0%B8%B1%E0%B8%95%E0%B8%95%E0%B9%8C-%E0%B8%A3%E0%B8%B8%E0%B9%88%E0%B8%99-EWE451BX-%0ADW-%E0%B8%AA%E0%B8%B5%E0%B8%82%E0%B8%B2%E0%B8%A7/p/10164294

the Electrolux service was here already 5 times, change parts, 2 times take it out for repair, but i worry that i not only have a "lemon", what could be solved by getting them to give me a new unit,

possibly that model might be wrong type?

https://goo.gl/photos/H8EjpSTgJT8S85aZ8

https://goo.gl/photos/Qxwit5Quq7kPNwrP6

[lopburi3]

Other water outlet? Are you using for multi-point hot water or just talking about lower flow rate because of another tap being open?

It would appear you may not have enough water flow to activate (and this is more powerful than most units which are 3.5kw so would make steam fast if flow slow).

This model does not appear to have English sales but normally there would be a flow sensor to turn off heater for low water flow - but might get some steam before there is enough cool water to stop the heating. You do have the input side flow value fully open and the filter screen is clean? Do you appear to have enough flow with cold water to get a good shower?

Have just returned an Electrolux dish washer for repair today so perhaps a bit jaded with the brand.

[KLL]

thanks for answering,

-a- it's a 4.5kW heater

-b- only for this shower used ( not multi-point ) see photo

-c- in case of the 2 times experienced steaming, there was NO FLOW of the shower at all, the sink tap was possibly in operation, so my question: how this unit works? by inlet water-pressure drop it starts heating?

-d- water flow for shower operation is good, i even reduce it ( by the 2 valves )

[lopburi3]

Without specific instructions it is hard to know exactly but normally there is a flow sensor that will cut power to heater if water flow becomes slight or none. But there are also several other methods that can be used or combined. Temp would be another sensor.

But these units are rated for a usage water pressure range and some detail this - and others do not mention it. But in general you do need good water flow for such heaters - and expect would not work most places without home water pump.

[KLL]

yes, difficult to find out what's in it,

- - i just put in the (32A) FUSE again, run water and it got very hot, even the temp dial was on OFF, so that is a electronic malfunction.

- - i take the FUSE out, and test water flow, i am able to hear a kind of double click when water valve open >25%, as no electric power it can only be from a mechanic pressure switch?, while i think a turbine flow would need electronic metering and relay operation what all needs power... and still might not hear a relay clicking.

but i could not hear a click when i open the sink water flow!

- - yes, i have town water and no pump, but as reported the real dangerous events like heating without shower water operation

should never happen, and needing a pump, when supply pressure too low, has a influence on that?

i would expect that the service would have stopped repairing the heater if he thinks there is not enough water to operate that type of heater??

[BaldPlumber]

What parts had the technician replaced already?

Does he leave it in a working state after fitting parts only for it to fail later?

[KLL]

yes after some board and sensor changes it worked for several tests and one shower, but latest after 2 days it starts failing again,

well, i clearly need a repaired / or better new unit,

but my question is if i might need a different type anyhow, i would so choose a different brand too.

some salesman open for me several models and suggested to use:

+ only the old type copper? heater units ( but he says they heat faster what i doubt?)

+ not the one with the old overload fuse and the plastic handle to operate that fuse ( why not?)

and my wife suggests just to use one of that cheap china copies like all thai people use! ( sounds reasonable )

but i am here because of the question what types are available? and how to find out which works on what principle?

and what are the corresponding limitations?

[lopburi3]

If you are located in Bangkok or below you may only need 3.5kw unit and I have found inexpensive Panasonic to be excellent (have 6 units of various brands - but all Japanese parent company). But you say 'town' water - does that mean a small village type source? Remember water in tanks can be very hot this time of the year during the day if they are in sun - but expect you did not have the same hot water from sink tap?

The breaker is normally RCB so very important it works (and unit still needs to be attached to real ground rod/wire). Some of the old version breakers could fail due the push up lever becoming frozen but have not seen that type in several decades (it was corrected in later versions).

http://www.lazada.co.th/panasonic-dh-3jl2th-3500-3922160.html

[Crossy]

A really daft question, you do have the inlet and outlet the right way round don't you (still got the instructions)?

My reason for asking is that there is what looks to be an overheat sensor on the right hand pipe, which is hooked up as the inlet.

EDIT OK belay that, found a user manual (in Vietnamese), shows it hooked up like our OP has it. That must be the flow sensor.

https://manualscollection.com/?fid=0830b042a1252017f126771ddfddf06c&read=online

[gandalf12]

A really daft question, you do have the inlet and outlet the right way round don't you (still got the instructions)?

My reason for asking is that there is what looks to be an overheat sensor on the right hand pipe, which is hooked up as the inlet.

EDIT OK belay that, found a user manual (in Vietnamese), shows it hooked up like our OP has it. That must be the flow sensor.

https://manualscollection.com/?fid=0830b042a1252017f126771ddfddf06c&read=online

NO such thing as a daft question Crossy you know that from many of the posts on TV

[KLL]

that looks like a nice unit and known brand,

but your remark RCB? means RCCB 15mA included? is ELB same?

http://electrical-engineering-portal.com/what-is-the-difference-between-mcb-mccb-elcb-and-rccb

yes, there is a earth wire connected to the unit ( and all power outlets too)

and the house also has a RCCB.

what i found there: http://www.lazada.co.th/electrolux-ewe451bxdw-aura-slim-series-4500-white-3667677.html

and google translated, sounds like my used unit has:

+ RCCB 15mA

+ flowswitch < 2l/min shutdown

+ tempswitch > 55degC shutdown

also sounds good but just don't work.

but how LAZADA know all this if at the Electrolux page is no spec at all?

so if my unit has a flow sensor what switches the heater ON if flow > 2l/min

how is that working? what type of sensors are that ( and what clicks even if there is no power? )

i also read about sister model EWE652BX-DW (Multipoint Slim Series) 6500Watt

what is the difference in sensors regarding multipoint? besides 2 valves on outlet side instead one on the inlet side?

town water

i understand about the temperature of the supply water, when the blue water pipes are along a street, not even covered by ground you can get water temperatures too hot to shower at the hot season ( like sonkran ) at early afternoon.

but what i reported is happening on the shower head only, and i not trust that unit to leave the power / fuse on anymore.

[lopburi3]

Yes there are a dozen names for sensor breaking circuit when there is a difference between live and neutral (meaning an alternative path to ground/you may be in the circuit). Also good to have upstream. Believe multi point only indicates flow control switch installed (but perhaps better quality then on a unit not intended to operate based on flow).

[KLL]

found a user manual (in Vietnamese), shows it hooked up like our OP has it. That must be the flow sensor.

https://manualscollection.com/?fid=0830b042a1252017f126771ddfddf06c&read=online

thanks, that is actually much more detailed as the available AX manuals i have,

on the water inlet ( right ) is first a sensor black with 2 brown wires (25)

and then the ?flow? sensor with many wires (24)

bad luck i not understand it,

just for fun here the google translation of the sensor 24 , 25 naming from that pdf

Putting? Ng l?

i nư? c

I?

drain

t?

c burners? i chicken

.

[DonaldBattles]

I live in Chiang Rai and find that the 4.5 kw heaters are not enough during cold weather. I am in the process of changing to a gas hot water heater. It will cost less to operate and will provide sufficient hot water during cold water. In Mae Si you can buy 20,000 BTU unit for 3500 Baht.

[lopburi3]

Gas heaters used to be the only type available - and total overkill for Bangkok as had to physically block most of the gas ports to keep temp below scalding most of the year. Be very aware they need good ventilation (people were dying often when these were being used 30 years ago). And most bathrooms had open windows in those days.

Perhaps just slowing the water flow during coldest weather might be enough to make 4.5kw usable? Works for me using 3.5kw here in Bangkok and am also of a higher age and not fond of cold water showers.

[KLL]

here the english circuit: ( for 451AX-DW )

https://goo.gl/photos/amQq1gvTezS2JHx76

and a photo of the internals of that AX model

https://goo.gl/photos/j9vYuPmEH3nQhnts9

i read about that the 4.5kW unit has a NOT resetable ( > 85degC ) thermostat

( must be replaced )

now i think that was the service action after the unit was not heating at all.

so i see that this unit has one heating element only

? the TRIAC is for ON / OFF or for temperature control?

the different vietnamese manual circuit indicates temperature control by thermostat setpoint potentiometer,

but i miss a symbol for a temperature sensor, only see temperature switches??

a reason why it can heat even if there is no water-flow at all could only be that the flow-sensor ( >2l/min ) is stuck or the

"Main Control PCB" is faulty.

i still have no idea what is the FLOW sensor or how it works.

GOOD MORNING THAILAND

this morning i tested again and the unit worked.

[lopburi3]

Do you have any way to check your electric power? The electronics might have an issue if have low voltage - find basic units seem to work better than the automatic types and are easy enough to turn hotter/cooler manually.

[KLL]

very good argument, yes the power is bad, my desktop UPS clicking all the time, nearby other building site, possible use same phase for welding??.

i will check by multimeter, but no osci available.

and i see under the upper PCB a old style transformer power-supply. possibly can measure DC there?

main: 227 VAC under load 204 VAC

DC 10V

[lopburi3]

Be careful - a transformer does not turn AC into DC. Just check in an outlet socket someplace as that will be much safer. I suspect power is good now and that is why running OK but when you normally shower it is likely very low.

[KLL]

update:

i asked the Electrolux service to check about water pressure and electric ( volt == pressure )

and "he jumped on that train "

we see volt jump down from 220 below 200.. 190 when heater on ( and good operation / no malfunction to show! )

we verify same also on the PEA electric counter ( the seal was gone long ago by some building workers ) , to check that the house internal wires and connections are OK

there is no spec about the min supply voltage, but the AX manual states operation at 220, 230, 240 VAC,

also the vietnamese BX manual.

-- but i am now facing the situation that i loose the chance to claim a new unit,

-- that i need to buy a smaller heater

-- that i doubt the newer "electronic" types

and the PEA thing??

i not want to open a new topic,

what is it about the "temporary" electric power ( with about 8 baht/kWh )

until you can have a house number... and can get the real contract ( at about 4 baht/kWh )

house must be finished 80% then can get house number, house book ( blue ) and register me ( house book ( yellow )?)

and can get post , telephone AND ?final? electric..

is there a limit 15A? limited by what?

[lopburi3]

15 amp meter is the normal single phase power for mid-larger homes here - 5 amp for older one room is normal - but that 15 amp meter provides up to 45 amps and is all most homes use with normal home main 63 amp breaker. Cost will likely be about 5 baht per unit.

Expect you may have issues when the voltage gets a bit lower - which may happen at night.

[KLL]

15 amp meter is the normal single phase power for mid-larger homes here but that 15 amp meter provides up to 45 amps and is all most homes use with normal home main 63 amp breaker. Cost will likely be about 5 baht per unit.

ok, i expect that in near future when the big house is built,

( but the temporary contract (for new land without house number..) and the near 8 baht/kWh bill now from PEA is REAL )

so i have to live with that bad PEA supply forever? AND i have to change

-- to 3.5kW heater unit

OR

-- to 3phase counter/contract and heaters?

and all means? single phase 4.5kW units are better not to be used? because they are out of spec for 90% of all house power supply / PEA contract? including the consequences that warranty question get difficult.

[Crossy]

A 15A meter (actually a 15/45) is good for 45A+, ours is on a 50A incomer. Multiple aircons, fairly meaty water heaters, pool, ponds, 5HP of irrigation etc.etc. it's never got near 50A.

Your temporary supply is almost certainly a 15/45, look at the meter.

It probably varies by area, but we had a PEA inspector round to look at the electrics before they would swap to a permanent supply. You will need your blue book in place in any case.

[KLL]

thanks

[KLL]

so it is correct that they will change the meter after you get house-number / book

( sounds very stupid, need for changing contract is already questionable. )

yes, i will look for meter info

_________________________________________________________________________

just to compare:

other house, contract, village

4.5kW heater brand Stiebel-Eltron

223VAC down to 204 VAC

so a 20V dip in the supply when you run a 4,5kW heater is very normal

and i think it should not effect the operation of electronics.. inside!!!!

any cheap switching power supply work from 85VAC up and supply const. DC for electronic...

other side, the heater is a normal resistor, it should work at any voltage, just not bring the expected power / water temperature.

safety switches like

++ LOW FLOW

++ HIGHT TEMP

work also independent from main voltage!!

but should disconnect the main and not be the "input" to some questionable electronic

[lopburi3]

Are you actually saying anything will work at 85v AC and up? Good luck with that theory. Suspect you may be thinking of 110/220 multi voltage low power items - not items designed to work at 220v?

Expect in fact you will find little will operate below 180v and even most lights will likely fail below about 160v

[KLL]

Are you actually saying anything will work at 85v AC and up? Good luck with that theory.

NO, i say a switching power supply to drive any DC electronic can work from 85VAC up.

and a heater element and its safety switches TSH, FSL have to work at any VOLT,

just might not produce very hot water at low volt

YES, i need good luck!

___________________________________________________________________________________________

TOO LATE

i just took a shower, water was very hot,

i turn the temperature dial down, still too hot

i turn the temperature dial to OFF, still too hot,

i press the TEST button and water gets COLD

i happen to meter the VAC : 207 when water hot. when water cold 230 VAC

i STOP the water flow

i press the RESET button

first little water come out, then steam ! water inlet valve closed ! ( that now happened 3 times already )

___________________________________________________________________________________________

can someone agree that that design / model is a health risk?

because it can not be ( only ) a faulty unit, it must be a design flaw

i like to send that heater in for a check,

like TÜV SÜD THAILAND Pathumthani?

but i worry they only want paid business inquiries

not so much work for customer protection...

[lopburi3]

You are likely running outside of its operating voltage range as automatic heater control seems bad (turn off unit power and no more heating). Much better to use dumb system where you move a rheostat type switch when using suspect voltage.

[Crossy]

KLL, your heater does not have a switch mode PSU, the heat control electronics is more akin to a large triac lamp dimmer.

207V should be fine to make it work correctly, since it is not are you certain you have adequate water pressure? You need to have a good flow from the shower head, with the flow at maximum the water should be hot but not scalding.

With the power off drop the shower head in a bucket and run the water for 60 seconds, measure the amount of water in the bucket (litres), that will give you a measure of the available flow rate, check against the heater instructions.

If there's enough water one can only conclude that the unit is defective, take it back for a refund / replacement with a heater of a different type.

We have a 3.5kW Panasonic which works well and didn't cost the earth.

[KLL]

-a- yes i suspect, that was just theory to say it should be possible to operate DC electronics with SWPS from 85VAC up,

so if my heater ?electronics? is sensitive already at 207VAC,

can call it bad luck or bad design?

would be nice if someone could confirm that 20VAC voltage drop with 4.5kW heater operation ( checked at any plug outlet )

( i see it at 2 locations already, so i would like to call it NORMAL and expect a heater design could cope with that )

-b- flowcheck ( both valve full open / same condition at my last shower )

2min11sec for 10L --> >4.5l/min

Much better to use dumb system where you move a rheostat type switch

i would agree to that now!

and OLD MAN, OLD HARDWARE, no problem..