Hot water heaters for showers

[MrGaoMungGawn]

I have a SolarHeart water heater on the roof,had it for 20 years,it was

expensive at the time,but I am quiet sure it has paid for its self,basically

maintenance free,even at cold times like now the water gets hot with

just a couple of hours of sun,in summer it gets scalding hot.

It works in showers ,bath,and have hot cold at sinks in kitchens,most

likely the best money i ever spent,they are quite expensive now at

around 200,000 bht.

regards worgeordie

The ones coming out of China, and used in China are MUCH cheaper.

[MrGaoMungGawn]

Yes we are both singing from the same hymn sheet.

I did say my 8kw shower is on a 40 amp breaker.

But they are not steam proof it seems

Sent via tin can and string after pigeon shot

So I was right then.....6K watts is just not enough for a few cold nights

[meechai]

So I was right then.....6K watts is just not enough for a few cold nights

Just depends on how much water (liters per minute) you need to heat

[ignis]

Have 2 Panasonic, used every day at least twice a day, will be 10 years old in March.. the downstais one is also used for washing all the dogs.

Have it on hot setting for myself and this weather have to turn down the water flow...

For something different then showers + is 6 years old but not used often but much hotter and very cheap as i remember called Ruska Happy

[worgeordie]

I have a SolarHeart water heater on the roof,had it for 20 years,it was

expensive at the time,but I am quiet sure it has paid for its self,basically

maintenance free,even at cold times like now the water gets hot with

just a couple of hours of sun,in summer it gets scalding hot.

It works in showers ,bath,and have hot cold at sinks in kitchens,most

likely the best money i ever spent,they are quite expensive now at

around 200,000 bht.

regards worgeordie

The ones coming out of China, and used in China are MUCH cheaper.

Yes you get what you pay for, would one from China be working in 20 years

time ? Doubt it

regards Worgeordie

[Dean1953]

Interesting topic, for me. I have 3 shower heaters in my house and all quit working about a year ago, after 5-6 years of service. Since I'm not living there, I'm in no hurry to replace them (although the house sitter can't be enjoying her showers) but would like to replace them with more reliable heaters when I get the house rented. It sounds like I would be better off getting a reputable electrician to do the installation properly and safely.

[TehBen]

Dragging up an old thread after being on the hunt for a water heater in HomePro today.

The assistant told me that while they sold Panasonic heaters (the on-demand type, obviously), you can not use them with normal shower heads, you have to buy a shower head and hose from Panasonic.

I'm serious. She was serious. I questioned it 4 or 5 times. She remained serious.

Is the thread different on the plastic connections or something? Surely she's just trying to push certain models.

[onthedarkside]

Dragging up an old thread after being on the hunt for a water heater in HomePro today.

The assistant told me that while they sold Panasonic heaters (the on-demand type, obviously), you can not use them with normal shower heads, you have to buy a shower head and hose from Panasonic.

I'm serious. She was serious. I questioned it 4 or 5 times. She remained serious.

Is the thread different on the plastic connections or something? Surely she's just trying to push certain models.

All the shower heads and hoses are interconnectable. Usually a half inch threaded fitting.

[kaptainrob]

^ Bull$hit.

They all come packaged with proprietary hose and spray head although you can go choose custom fittings. Only no-no would be say 'rain-shower' heads.

[Thighlander]

I'm in the process of changing my electrolux over from the sprayer it came with to a traditional shower head. It's standard half inch plastic out of the HWH. The existing hose on the other end is not half inch, but built specifically for that sprayer. I will connect a standard water line from the hwh to the nipple on the steel pipe, which will hold the new shower head. What is a "standard" showerhead? Some showerheads require a certain flow, or won't work well at all. I've been using the Delta ater Sense that only requires 5.8 lpm +/-, and gives a great shower. Older models mat require 8 lpm. Checking your output with a bucket is a good start. Unfortunately, I can't find Delta here. This is one of the best I have ever installed. I see they are selling that Kohler "Moxie" in the US just like they are advertising here, so I'm going to read up on it. But check out "water sense" technology; truly amazing.

http://www.homedepot.com/p/Delta-1-Spray-1-5-gpm-Water-Efficient-Showerhead-in-Chrome-52653-PK/203124918?MERCH=REC-_-PIPHorizontal1-3-_-NA-_-203124918-_-N#specifications

[CaptainTyphoon]

As you can see, we just installed this heater today. It is a 4000/8000 watt unit.

BUT, upon turning it on, I would say it is not hot.

Before purchasing this, I read carefully the comments which were submitted above.

They were good comments, but I could not find a Panasonic.

And anyway, last winter I used a Panasonic 6000 watt jobby, and it was NOT HOT, also.

So, I would say that if you really want a lot of hot water for your shower, then you need maybe more than 10,000 watts.

But here is what you must consider, as was also mentioned by the more science based comments above:

The temperature of the water which is produced by the machine will vary according to the volume, or flow, of water coming out of your pipe.

In my case, I had the water valve wide open. But since there is not much pressure, I would say it is just normal to low flow rate.

Still, not water hot, or hot water not.

I can foresee that this winter i will need to turn down the flow of watter, in order to get the desired temperature.

The only alternative to this would be to buy a really high class machine, which might be fit for someone like Dick Cheney.

And then the 13000 watt machine was about Baht15000. Far too much for me, as this is just basically for myself, and also in case I wish to wash a dog or two that happen by.

I have noticed that here where I am, sometimes people will just wash the dogs for free, even though they do not know the dogs.

I do not think they use hot water, however.

So, please keep this in mind:

FLOW rate

Wattage.

This is the ONLY way to predict what the rise in water temperature will be.

I have read above that there is much consternation, with some saying one machine is hotter than another machine.

But, there is NO DATA of a scientific nature, such as discussion of flow rates, incoming temperature, outgoing temperature in degrees F, C, or Kelvin, for that matter.

So, basically just useless information if you want to know about water temperature you can expect

But then again, what do we usually expect here?

It is OK, though. And I DO APPRECIATE what I read, and I copied it down and took it with me to the store, at power buy, and to Bahn Tomorrow.

I bought from Bahn Tomorrow, and the lady there was very helpful, and her English was quite good.

I appreciate when the sales people show they care, and are polite.

I am generally very happy with the appearance since it is white, and I told them not to put on any yellow, green and red stickers.

The Germans have good styling also, in case we have any German readers.

Before I installed this machine, I had a Sharp 33, 3500 watt heater. It was useless, and the water would be cold unless I turned the flow rate way down.

I do not take showers with my GirlFriend, since I have none at this point in my life, and do not want one.

However, if I did, I would definitely get a 13000 watt jobby, and I would put some handholds on the wall, and some non-stick surfaces on the floor.

Ok, Hope this helps everyone...

[CaptainTyphoon]

We have a stiebel eltron 8kw water heater, actually its great multipoint...it feeds 3 rainshower heads concurrently in different rooms.

Cost 7500bt, and as its german engineering you expect the price to be higher.

Its fair to say though like all electric showers if you don't have the pressure to send the water through the heater it will never work no matter how many bells and whistles your heater has.

By comparison I don't think you can buy an electric shower less than 7.5kw in the UK.....you can generate 3.6kw of heat by farting I think.

Sent via tin can and string after pigeon shot

As I mentioned above, I just bought the same one, picture attached.

However, I beg to differ with you regarding what I observed.

For one thing, using relatively normal water pressure with the valve wide open, and today being a fairly hot day, weatherwise, I was able to hold my had in the hot water stream without burning it, and with the temperature on Max setting.

What i want is to be able to turn the water on Max and to get hot water that is really hot.

As you know, if you have a hot water tank, if you turn on the hot water, only, you will definitely get scalded. So, I want it that hot. This way, when winter sets in, I won't freeze while taking a shower.

I did try to fart to add a bit of heat to the stream, however this did not work, either.

[beau thai]

As Eyecatcher pointed out, anything above ~3,500watts will require a heavier breaker than standard ~16amp. Check your Load Centre breakers now!

Water pressure, if too high/flow too strong, will reduce output temp. Very noticeable this time of year as supply water is ~10 degrees colder. One may reduce pressure on the inlet side of heater easily enough however this reduces water spray strength. Fitting a more appropriate spray head and/or a 25 satang restricting (water-saver) washer in the outlet hose is the best way to go.

Fitting a more appropriate spray head and/or a 25 satang restricting (water-saver) washer in the outlet hose is the best way to go.

Until reading recent threads here I was pretty relaxed about my 4.5kw Imarflex as I thought it was ok on half heat. But now I look more closely I am on 3/4 already. I then checked the temps - 29c unheated, and only 38c on full power. Feels hot but not too hot, which it was earlier in the year.

If it only raises the temp 9c, in the winter that will only give an uncomfortably cold shower same as last winter, so I would welcome more info please on what constitutes a 'more appropriate' spray head, and where to get the restricting water saver washer, without my question generating a blank look and a 'Mai Mii'

And I suspect I will also need to buy a much more powerful heater by December- 8kw or more.

[AnotherOneAmerican]

Just use the shower head that came with the heater.

It will solve your problem.

[habfan]

Have 2 Panasonic 3.6k which are hopeless,even with the low water pressure barely warm now.

Same here, but ya know I only turn the pathetic thing on on the coldest of cold season days and on those days you better have your shower before the sun goes down.

[Thighlander]

You gotta have proper gauge wire, too. My 4500 will burn me on high. Waiting on delivery of Water Sense showerhead from the US. One knowledgeable person at the home store would be a lot more helpful than 12, who are not.......

[jobin]

Are not electric hot water heaters with small, 5/10 gallon, storage tanks available? Turn on, wait 20 mins and have scalding hot 5 gallons, enough when diluted down for 3 consecutive showers. Temp setting variable. Switch unit off when not needed. Inflow water temp; not important, but does take a bit more time to reach highest out water temp.

[JDGRUEN]

And don't forget, the higher wattage heaters need a higher ampage circuit breaker...40amp.

Advisable to fit a breaker though regardless of the wattage....just in case.

Sent via tin can and string after pigeon shot

I agree with this.

Also, I have toured much of Thailand in the past 7 months and thus have sampled many different brands of electric heaters --- The German / European brands were much better across the board ... But I think the real problem is how it is wired -- Cable gauge may be subpar and cannot carry the higher amps or the voltage being delivered is below minimum and the heater is just not kicking into high gear..... I felt this was the case for rented rooms where the landlord was paying the bill - not much electricity used and done deliberately.

I have an analogy for this that demonstrates my theory.... I have used electric motors over my life where insufficient amps or voltage was being delivered -- the motors would run but not near at full speed.

I am not sure if changing breakers will do the trick - if the cable gauge is not sufficient to carry the greater amperage. The cable could get hot and melt the plastic coating or worse.

OP - if you can find an electrician who can understand what you want tested and determine if the cable is of sufficient gauge - then your problem might be identified and may be able to be fixed... Bottom line the required volts / amps should be printed inside the unit cover or in the literature ... a correctly performed volt/amp test on the line should reveal what is going on...

Builders do make short cuts ... and this one may have stabbed you. The better idea may be a gas unit... as evidenced by some of the posts.

Also when and where possible I suggest exploring the idea of a solar preheater... one can be made from a dark colored hose - coiled outside - then fed into the cold water intake ... The water will be very hot going into the heater on even an overcast day... This would be good for a test ... more sophisticated solar water heating devices - made inexpensively can be found demonstrated on Youtube. I like the idea of a hose or flexible pipe - coiled in a 1.5 meter parabolic shaped satellite dish (the see through metal screen type) available for about 1000 Baht - hose and connectors at one of the Home Stores... just and idea...

To see for yourself the dramatic temperature rise ... just put a section of hose out in the sun with the water on and the end capped. It won't take long - and watch out it will burn you.

,

[beau thai]

Just use the shower head that came with the heater.

It will solve your problem.

Needless to say, water heaters are lined up against more than 50 others in many stores so they compete on price.

You think they are going to give you a high quality shower head, and either reduce their profit per piece , or volume sold? Nah! They give you cheap stuff which is why Thighlander is importing a good one for his use.

[beau thai]

Looked at a stiebel 6kw at Central in KSK today and on asking the price was told it was 'only for show' . I pointed at the slightly different 6kw stiebel adjacent and was told that was 'only for show' as well.

The girl was quite unfazed by my incredulous expression and probably went back to playing on her phone.

Time these places set sales targets, and fired non-performers and rewarded those that work. TiT

[CaptainTyphoon]

Looked at a stiebel 6kw at Central in KSK today and on asking the price was told it was 'only for show' . I pointed at the slightly different 6kw stiebel adjacent and was told that was 'only for show' as well.

The girl was quite unfazed by my incredulous expression and probably went back to playing on her phone.

Time these places set sales targets, and fired non-performers and rewarded those that work. TiT

If anyone is still interested in this subject, I have now become a real expert, and I have learned that most of the information provided by the big box stores is garbage, and that the information provided here on this thread is also questionable, since it does not list any data references. Where are you people gettting your data? Out of your heads?

So, Stiebel Eltron does provide on its company site all the information you need to buy the right size heater.

Just please go to the site and find the graphs of data.

They will tell you how much each machine will raise the water temperature for a host of various flow rates.

But, says you. How do I know my flow rate?

This is easy, and you just need to use your own noggin, instead of not thinking.

What I did, I got 6 empty Coke Zero Bottle, which are 1.25 liters.

I then turned on the water, full blast and filled up the bottles one after the other for exactly one minute.

I measured 6,6 liters per minute of flow rate.

With this value, I looked at one axis of the table provided by the manufacturer for each size machine.

In my case, since I live in the Northern Part of Thailand, I will need to raise the water temperature from approximately 10 degrees in the winter time to about 35 degrees C.

In order to do this, when I have a flow rate of 6.5 liters per minute (which is not high), I will need about 10 to 12 Kilowatts of power.

Unfortunately, Stiebel Eltron only provides this size water heater in Phase 3 or with voltage of 380 to 440 volts.

Since I do not have access to this kind of power, and only have single phase, then I am up the creek without a paddle.

My solution will therefore need to be:

I have already bought the 8000 watt unit. But, if I want the water hot enough in the winter here, I will need to slow down the flow rate to about 4 liters or maybe less per minute.

For me, this is a hardship, because I like lots of water when I shower, and I like it hot.

So, now you know, and there should be no further uninformed questions or remarks here if you would just read my comment here, and also refer to the data clearly provided by every major manufacturer.

I am very happy to help you guys out.

No need to thank me, in fact.

Bye now......

[jobin]

Consider an alternative solution. Install an insulated tank, say 1000 liters, which SHOULD be enough for shower. Heat this water prior to your needs. Now, rather than water at 10*, the inflow will be 25* which will then be further heated to 37*, or whatever you choose. Yeah, tank needs gravity flow to heater, unless small pump also installed, and some plumbing valves and pipes.

I did mention, before, the hot water tank, about 10 gals, which is NOT continuous flow. With this method the inflow water temp is immaterial. Dial up 40*, wait some mins, get 40* hot water. If water near freezing, must wait longer. Would also mention that in the colder weather, fewer showers are generally needed. And further mention that the hotter is the shower water, the more possible 'damage' to skin, mostly removal of natural oils, which hastens dry skin, itchiness. etc.

[Thighlander]

Here is the American Standard shower head that I imported from the US. It cost about 10 USD, and is Water Sense certified. Maximum flow is <6 lpm. There is a gear driven propeller type device that rapidly rotates the spray and makes you feel like you are using much more water than you actually are. This is the newer technology and beats the heck out of the older style that simple have a regulator restricting water flow.

They do have some here with a green "Eco" label, but they are 900 thb and up.....but that is what you should look for if you want to purchase a water saver here, and of course less water means you can make it hotter, and save $$$$.

[opalred]

gas is cheaper to run and can buy many brands at mae sai 3000 bht

[CaptainTyphoon]

gas is cheaper to run and can buy many brands at mae sai 3000 bht

I do agree that gas is cheaper to operate, IF one has access to cheap bottled gas.

But where I used to live, 18 Kilograms of gas cost about 25USD and would not last long.

Now, I use the Stiebel Eltron, and while this 8000 watt unit will not put out as many BTU as the gas jobby, it is MUCH easier to operate, and by this I mean that I don't need to worry about batteries to start the spark, and also worry about wind blowing the thing out, and I also don't like the jet engine sound, even though not loud.

Have you really calculated the cost per BTU? Based on the present cost per KG of gas?

And, do you like to lift those heavy 18 kilogram bottles?

And what about when you drop one of them on your toe, with its sharp circular edge at the bottom of every bottle.

No, my days of lugging around bottles is at an end, and good riddance to heavy bottles, says I. ((The higher quality gas burners are expensive, and almost the same as the electric, with the one I used costing about 9000 Baht for one hot enough to run a single shower in the winter time with enough flow rate for my comfort.))

Edited September 6, 2014 by CaptainTyphoon

[beau thai]

Looked at a stiebel 6kw at Central in KSK today and on asking the price was told it was 'only for show' . I pointed at the slightly different 6kw stiebel adjacent and was told that was 'only for show' as well.

The girl was quite unfazed by my incredulous expression and probably went back to playing on her phone.

Time these places set sales targets, and fired non-performers and rewarded those that work. TiT

If anyone is still interested in this subject, I have now become a real expert, and I have learned that most of the information provided by the big box stores is garbage, and that the information provided here on this thread is also questionable, since it does not list any data references. Where are you people gettting your data? Out of your heads?

So, Stiebel Eltron does provide on its company site all the information you need to buy the right size heater.

Just please go to the site and find the graphs of data.

They will tell you how much each machine will raise the water temperature for a host of various flow rates.

But, says you. How do I know my flow rate?

This is easy, and you just need to use your own noggin, instead of not thinking.

What I did, I got 6 empty Coke Zero Bottle, which are 1.25 liters.

I then turned on the water, full blast and filled up the bottles one after the other for exactly one minute.

I measured 6,6 liters per minute of flow rate.

With this value, I looked at one axis of the table provided by the manufacturer for each size machine.

In my case, since I live in the Northern Part of Thailand, I will need to raise the water temperature from approximately 10 degrees in the winter time to about 35 degrees C.

In order to do this, when I have a flow rate of 6.5 liters per minute (which is not high), I will need about 10 to 12 Kilowatts of power.

Unfortunately, Stiebel Eltron only provides this size water heater in Phase 3 or with voltage of 380 to 440 volts.

Since I do not have access to this kind of power, and only have single phase, then I am up the creek without a paddle.

My solution will therefore need to be:

I have already bought the 8000 watt unit. But, if I want the water hot enough in the winter here, I will need to slow down the flow rate to about 4 liters or maybe less per minute.

For me, this is a hardship, because I like lots of water when I shower, and I like it hot.

So, now you know, and there should be no further uninformed questions or remarks here if you would just read my comment here, and also refer to the data clearly provided by every major manufacturer.

I am very happy to help you guys out.

No need to thank me, in fact.

Bye now......

I know you said no need to thank you but I will anyway! Just conducted my own experiment and, of course, you are correct.

Didnt feel the need to fill containers for 1 minute- 20 seconds was enough, just multiply by 3 obviously! The water flow was just over 8l/minute. The mains stopcock is in the bathroom which made it easy.

Turned it down to 3l which was enough for handwash etc, but not for my shower head. The minimum I can get away with is 5l. But-- at that flow rate, my water now heats to 45c whereas at 8l it only heats to 38c, which is about 10c above 'cold'. So in winter when the night temp outside drops to say 16c, then my shower will be 31c. Better but still equivalent to 'cold' water today.

Thinking a 'water-saver' shower head was the solution, I checked online. They boast proudly of operating at flows of 1.5gpm (6.75l), and those that are designed to operate at 5l get very poor reviews - and offer no improvement over my existing new 'premium but normal' shower head.

Seems no option other than turn down the flow rate as you say AND buy a more powerful heater than my Imarflex 4.5kw. My new 6kw is on order.

I hope that, at a 5l flow rate, it will raise the temp 20c on max- we will see.

You mention a flow rate of 4l - have you found a shower head that will work satisfactorily at that level- including washing long, thick thai hair?? (gf not me.)

And if all this seems a bit anal to other readers- sorry, but I dont enjoy cold showers!

[Thighlander]

Looked at a stiebel 6kw at Central in KSK today and on asking the price was told it was 'only for show' . I pointed at the slightly different 6kw stiebel adjacent and was told that was 'only for show' as well.

The girl was quite unfazed by my incredulous expression and probably went back to playing on her phone.

Time these places set sales targets, and fired non-performers and rewarded those that work. TiT

If anyone is still interested in this subject, I have now become a real expert, and I have learned that most of the information provided by the big box stores is garbage, and that the information provided here on this thread is also questionable, since it does not list any data references. Where are you people gettting your data? Out of your heads?

So, Stiebel Eltron does provide on its company site all the information you need to buy the right size heater.

Just please go to the site and find the graphs of data.

They will tell you how much each machine will raise the water temperature for a host of various flow rates.

But, says you. How do I know my flow rate?

This is easy, and you just need to use your own noggin, instead of not thinking.

What I did, I got 6 empty Coke Zero Bottle, which are 1.25 liters.

I then turned on the water, full blast and filled up the bottles one after the other for exactly one minute.

I measured 6,6 liters per minute of flow rate.

With this value, I looked at one axis of the table provided by the manufacturer for each size machine.

In my case, since I live in the Northern Part of Thailand, I will need to raise the water temperature from approximately 10 degrees in the winter time to about 35 degrees C.

In order to do this, when I have a flow rate of 6.5 liters per minute (which is not high), I will need about 10 to 12 Kilowatts of power.

Unfortunately, Stiebel Eltron only provides this size water heater in Phase 3 or with voltage of 380 to 440 volts.

Since I do not have access to this kind of power, and only have single phase, then I am up the creek without a paddle.

My solution will therefore need to be:

I have already bought the 8000 watt unit. But, if I want the water hot enough in the winter here, I will need to slow down the flow rate to about 4 liters or maybe less per minute.

For me, this is a hardship, because I like lots of water when I shower, and I like it hot.

So, now you know, and there should be no further uninformed questions or remarks here if you would just read my comment here, and also refer to the data clearly provided by every major manufacturer.

I am very happy to help you guys out.

No need to thank me, in fact.

Bye now......

I know you said no need to thank you but I will anyway! Just conducted my own experiment and, of course, you are correct.

Didnt feel the need to fill containers for 1 minute- 20 seconds was enough, just multiply by 3 obviously! The water flow was just over 8l/minute. The mains stopcock is in the bathroom which made it easy.

Turned it down to 3l which was enough for handwash etc, but not for my shower head. The minimum I can get away with is 5l. But-- at that flow rate, my water now heats to 45c whereas at 8l it only heats to 38c, which is about 10c above 'cold'. So in winter when the night temp outside drops to say 16c, then my shower will be 31c. Better but still equivalent to 'cold' water today.

Thinking a 'water-saver' shower head was the solution, I checked online. They boast proudly of operating at flows of 1.5gpm (6.75l), and those that are designed to operate at 5l get very poor reviews - and offer no improvement over my existing new 'premium but normal' shower head.

Seems no option other than turn down the flow rate as you say AND buy a more powerful heater than my Imarflex 4.5kw. My new 6kw is on order.

I hope that, at a 5l flow rate, it will raise the temp 20c on max- we will see.

You mention a flow rate of 4l - have you found a shower head that will work satisfactorily at that level- including washing long, thick thai hair?? (gf not me.)

And if all this seems a bit anal to other readers- sorry, but I dont enjoy cold showers!

1.5 gpm would be 5.67 lpm....and they work exceptionally well.

[beau thai]

Looked at a stiebel 6kw at Central in KSK today and on asking the price was told it was 'only for show' . I pointed at the slightly different 6kw stiebel adjacent and was told that was 'only for show' as well.

The girl was quite unfazed by my incredulous expression and probably went back to playing on her phone.

Time these places set sales targets, and fired non-performers and rewarded those that work. TiT

If anyone is still interested in this subject, I have now become a real expert, and I have learned that most of the information provided by the big box stores is garbage, and that the information provided here on this thread is also questionable, since it does not list any data references. Where are you people gettting your data? Out of your heads?

So, Stiebel Eltron does provide on its company site all the information you need to buy the right size heater.

Just please go to the site and find the graphs of data.

They will tell you how much each machine will raise the water temperature for a host of various flow rates.

But, says you. How do I know my flow rate?

This is easy, and you just need to use your own noggin, instead of not thinking.

What I did, I got 6 empty Coke Zero Bottle, which are 1.25 liters.

I then turned on the water, full blast and filled up the bottles one after the other for exactly one minute.

I measured 6,6 liters per minute of flow rate.

With this value, I looked at one axis of the table provided by the manufacturer for each size machine.

In my case, since I live in the Northern Part of Thailand, I will need to raise the water temperature from approximately 10 degrees in the winter time to about 35 degrees C.

In order to do this, when I have a flow rate of 6.5 liters per minute (which is not high), I will need about 10 to 12 Kilowatts of power.

Unfortunately, Stiebel Eltron only provides this size water heater in Phase 3 or with voltage of 380 to 440 volts.

Since I do not have access to this kind of power, and only have single phase, then I am up the creek without a paddle.

My solution will therefore need to be:

I have already bought the 8000 watt unit. But, if I want the water hot enough in the winter here, I will need to slow down the flow rate to about 4 liters or maybe less per minute.

For me, this is a hardship, because I like lots of water when I shower, and I like it hot.

So, now you know, and there should be no further uninformed questions or remarks here if you would just read my comment here, and also refer to the data clearly provided by every major manufacturer.

I am very happy to help you guys out.

No need to thank me, in fact.

Bye now......

I know you said no need to thank you but I will anyway! Just conducted my own experiment and, of course, you are correct.

Didnt feel the need to fill containers for 1 minute- 20 seconds was enough, just multiply by 3 obviously! The water flow was just over 8l/minute. The mains stopcock is in the bathroom which made it easy.

Turned it down to 3l which was enough for handwash etc, but not for my shower head. The minimum I can get away with is 5l. But-- at that flow rate, my water now heats to 45c whereas at 8l it only heats to 38c, which is about 10c above 'cold'. So in winter when the night temp outside drops to say 16c, then my shower will be 31c. Better but still equivalent to 'cold' water today.

Thinking a 'water-saver' shower head was the solution, I checked online. They boast proudly of operating at flows of 1.5gpm (6.75l), and those that are designed to operate at 5l get very poor reviews - and offer no improvement over my existing new 'premium but normal' shower head.

Seems no option other than turn down the flow rate as you say AND buy a more powerful heater than my Imarflex 4.5kw. My new 6kw is on order.

I hope that, at a 5l flow rate, it will raise the temp 20c on max- we will see.

You mention a flow rate of 4l - have you found a shower head that will work satisfactorily at that level- including washing long, thick thai hair?? (gf not me.)

And if all this seems a bit anal to other readers- sorry, but I dont enjoy cold showers!

1.5 gpm would be 5.67 lpm....and they work exceptionally well.

Thanks- my mistake. Maybe the US Gallon at 0.83 Brit gallon, is the only US thing smaller than UK equivalent??!! 555

Spent a while browsing the large range of shower heads in Baan & Beyond today- the concept of flow rates though is certainly 'Beyond' the knowledge of their staff.So no luck yet. Some of the low flow heads achieve apparent power by adding air- but not sure that adding cold ambient air would help achieve hotter water, only use less water.

[Thighlander]

The Brits "waddle" a lot more, that's for sure. Strange things happen, when island people breed.

[beau thai]

The Brits "waddle" a lot more, that's for sure. Strange things happen, when island people breed.

What?? 'Waddle'?? Maybe lost in translation from US english to English English?? Dont follow youir meaning or the connection with showers.

I guess a lot of Island people breed, and emigrate- to Australia, Manhattan Island, Staten Island etc etc