Hot Cold Water Mixer Tap And 8000W Instant Heater

[reflectionx]

Planning to install the Panasonic DH-8BM1T 8000W instant water heater to feed hot water to bathtub, sink and rain shower. Now, I was planning to use the sinlge lever mixing taps, like this one:

http://www.light-and-bath.com/index.php?lay=show&ac=cat_show_pro_detail&cid=52549&pid=227116

But, wifey said that on some Thai forum someone wrote that this is problematic and should use a dual handle - e.g.

http://www.light-and-bath.com/index.php?lay=show&ac=cat_show_pro_detail&cid=52549&pid=206888

The person did not say what could the issue be, but mentioned something like that even when the heater is set at 4500W, the water is way too hot for shower, so should not use single lever.

Any thoughts?

Thanks.

[rucus7]

We have 6000 watt units. One bathroom has double handle mixer one has single with no problems. The problem is in the kitchen single mixer, it is either scalding, or cold almost impossible to get it to mix correctly. It was the most expensive fixture we purchased. So in answer to your question some fixtures are problematic. With double handle no problem for sure. I was talking about bathroom showers the bathroom sinks have single handle without problem. By the way 8000 watt is a good idea especially if you have a rain design shower head. I will replace with 8000 when ours stop working.

[reflectionx]

We have 6000 watt units. One bathroom has double handle mixer one has single with no problems. The problem is in the kitchen single mixer, it is either scalding, or cold almost impossible to get it to mix correctly. It was the most expensive fixture we purchased. So in answer to your question some fixtures are problematic. With double handle no problem for sure. I was talking about bathroom showers the bathroom sinks have single handle without problem. By the way 8000 watt is a good idea especially if you have a rain design shower head. I will replace with 8000 when ours stop working.

Thanks,

Which brand and model do you use in the kitchen (the one that gives you trouble) and which one in the bathroom that does the job?

I am leaning toward VRH. The problem is that I can't find somehow matching set with double handles. I am looking at the following:

rain shower:

http://www.light-and-bath.com/index.php?lay=show&ac=cat_show_pro_detail&cid=52549&pid=227116

over the counter bassin:

http://www.light-and-bath.com/index.php?lay=show&ac=cat_show_pro_detail&cid=52549&pid=206664

bathtub:

http://www.light-and-bath.com/index.php?lay=show&ac=cat_show_pro_detail&cid=52549&pid=206870

[kwonitoy]

I've got three single handle mixers type fixtures in my condo, 2 6000watt for the sinks in the kitchen and bathroom and a 8000 watt for the shower.

The sinks as rucus says can run cold to very hot with a real small adjustment, the shower doesn't get changed as much, just set it where it's comfortable and it stays there so it doesn't seem to be a problem.

If I was to do it again I would use the two tap set up

[reflectionx]

thanks. Unfortunately VRH does not have much choice of 2 handle. What other budget brand is recommended?

[rucus7]

We have a two handle VRH in the one shower rain type with a satin stainless finish. It also has a flexible stainless wand. The kitchen single handle is HANG manufacture. One bathroom sink has a single handle HANG that mixes fine. Go figure. The other shower single handle is a COTTO no mixing problems. Good luck

[bankruatsteve]

Suggest you do not get a "budget brand". Get something true stainless steel or like that. I have several installations that I wish I did that: they have turned black and look terrible. OK - we have used some chemicals to make them look better but if they had been stainless steel it wouldn't be a problem.

[reflectionx]

Suggest you do not get a "budget brand". Get something true stainless steel or like that. I have several installations that I wish I did that: they have turned black and look terrible. OK - we have used some chemicals to make them look better but if they had been stainless steel it wouldn't be a problem.

That's why I am looking at VRH. Apparently they are some sort of commercial grade.

[reflectionx]

How about Cotto mixers? Any good? I finally found a double handle collection that I like: TERRANOVA.

They have two types - the glossy:

http://www.cotto.co.th/en/product/8852410200127

and the matte version:

http://www.cotto.co.th/en/product/8852410201360

I really like the matte version more, but I can't seem to find matte shower head and shower arm.

Aside from aesthetics, any other reasons to go for matte finish (e.g. durability)?

[Ackybang]

Hi reflectionx - Many of the American Standard, Cotto, VRH mixers all good, and they keep their ranges for Years, which means you can always get spares.

Just make sure when you select that you don't get the restricted flow rate 'eco' ranges, makes for an unenjoyable shower experience - many shower heads / taps also have removable filters in them which you might want to take out.

Also, using a constant pressure pump will give you good results - especially with water temperature fluctuations.

I must say, I do like the build quality and understated design of the VRH stuff - much prefer the matt stainless to the chrome gear...

For my rain shower set-ups and baths, I have installed for other people, and from this experience I'll be installing a 150 liter Stiebel immersion heater, with a high flow rate Grundfos constant pressure pump for hot / cold supplies to the house - gives superb results, power wise, and the immersion heater puts out hot water at the same pressure you put it in, as opposed to instantaneous jobbies, which tend to restrict the flow rate somewhat more. Fills a bath quickly, great shower, and uses less electricity heating wise - excellent guarantees / build quality, also.

I've never used instant heaters other than Siemens or Stiebel - really good quality, and depending on the model, you can wire them in many different configurations, in many different ways - single to 3 phase to adjust wattage / maximum temperature. Although I like some of the cotto stuff - I must say, I installed a system for a friend (that he chose) - quite a few Years ago - very expensive rain shower all in one - the build quality didn't seem so solid, and within a Year it looked like crap, although cotto taps I've installed for people have been great. Aesthetics aren't covered under their guarantee, but faults are.. Check everything really well before you buy, as some of these fixtures are not cheap, eh.

Good luck.

[reflectionx]

H

I've never used instant heaters other than Siemens or Stiebel - really good quality, and depending on the model, you can wire them in many different configurations, in many different ways - single to 3 phase to adjust wattage / maximum temperature. Although I like some of the cotto stuff - I must say, I installed a system for a friend (that he chose) - quite a few Years ago - very expensive rain shower all in one - the build quality didn't seem so solid, and within a Year it looked like crap, although cotto taps I've installed for people have been great. Aesthetics aren't covered under their guarantee, but faults are.. Check everything really well before you buy, as some of these fixtures are not cheap, eh.

Good luck.

Thanks for your detail input. However, I was under the impression that tankless water heater use less energy than conventional??? Energy savings is th main advantage listed on any website out there

[mogandave]

Not to sound glib, but the tankless heaters only use less power when you’re not using them. If you use a lot of hot water and use it frequently, a conventional hot water heater is cheaper to operate. Remember, all the studies that show
the cost savings are from people selling them.

I’m not knocking tankless, I love me some hot-water, but you may or may not see savings over a conventional.

As far as the single lever, I’d guess the Thai-guy that said it wouldn’t work probably didn’t know it was a
mixer.

[ETatBKK]

tankless - if you have just one or two users, and 2 to 3 shower round per day, it may save.

tank - if you have kids and need number of shower rounds anytime of the day, then go for a conventional tank.

[Mike45]

Hi reflectionx - Many of the American Standard, Cotto, VRH mixers all good, and they keep their ranges for Years, which means you can always get spares.

Just make sure when you select that you don't get the restricted flow rate 'eco' ranges, makes for an unenjoyable shower experience - many shower heads / taps also have removable filters in them which you might want to take out.

Also, using a constant pressure pump will give you good results - especially with water temperature fluctuations.

I must say, I do like the build quality and understated design of the VRH stuff - much prefer the matt stainless to the chrome gear...

For my rain shower set-ups and baths, I have installed for other people, and from this experience I'll be installing a 150 liter Stiebel immersion heater, with a high flow rate Grundfos constant pressure pump for hot / cold supplies to the house - gives superb results, power wise, and the immersion heater puts out hot water at the same pressure you put it in, as opposed to instantaneous jobbies, which tend to restrict the flow rate somewhat more. Fills a bath quickly, great shower, and uses less electricity heating wise - excellent guarantees / build quality, also.

I've never used instant heaters other than Siemens or Stiebel - really good quality, and depending on the model, you can wire them in many different configurations, in many different ways - single to 3 phase to adjust wattage / maximum temperature. Although I like some of the cotto stuff - I must say, I installed a system for a friend (that he chose) - quite a few Years ago - very expensive rain shower all in one - the build quality didn't seem so solid, and within a Year it looked like crap, although cotto taps I've installed for people have been great. Aesthetics aren't covered under their guarantee, but faults are.. Check everything really well before you buy, as some of these fixtures are not cheap, eh.

Good luck.

What type of pipe do you use for the hot water in the house?

[jbrain]

We have 6000 watt units. One bathroom has double handle mixer one has single with no problems. The problem is in the kitchen single mixer, it is either scalding, or cold almost impossible to get it to mix correctly. It was the most expensive fixture we purchased. So in answer to your question some fixtures are problematic. With double handle no problem for sure. I was talking about bathroom showers the bathroom sinks have single handle without problem. By the way 8000 watt is a good idea especially if you have a rain design shower head. I will replace with 8000 when ours stop working.

Thanks,

Which brand and model do you use in the kitchen (the one that gives you trouble) and which one in the bathroom that does the job?

I am leaning toward VRH. The problem is that I can't find somehow matching set with double handles. I am looking at the following:

rain shower:

http://www.light-and-bath.com/index.php?lay=show&ac=cat_show_pro_detail&cid=52549&pid=227116

over the counter bassin:

http://www.light-and-bath.com/index.php?lay=show&ac=cat_show_pro_detail&cid=52549&pid=206664

bathtub:

http://www.light-and-bath.com/index.php?lay=show&ac=cat_show_pro_detail&cid=52549&pid=206870

I have the two latter ones for the showers and the bathroom sinks and quite happy with them for little over a year now. They don't discolor, but keep in mind they are " Thai stainless " so if they stay wet all the time they will get a rusty layer but which is easily removable.

Thai stainless you will notice is also magnetic

For the bath tub I have the version with two seperate knobs

I have 6000 watt units for shower and sinks which are fine and a 9000W unit for the bath tub which in my opinion would have been better a 12000W unit.

Edited May 17, 2013 by jbrain

[mogandave]

I have a 12 year old 50 gallon conventional that takes care of the whole house.

[Ackybang]

Reflectionx said :

Thanks for your detail input. However, I was under the impression that tankless water heater use less energy than conventional??? Energy savings is th main advantage listed on any website out there

Hey mate - whatever makes you happy - it's your dollar.

The tanks I've installed have different temperature settings - aswell as normal and economy element settings, are well lagged, and on a thermo. Turn one off that's up to temperature, and the water stays hot for hours. You can operate them on a timer, aswell as the fact that because of the insulation, when you push the hot water out with the cold, (bear in mind ambient water temp here is usually in the 20's - and if you have a tank outside, it may reach much higher temperatures) the cold becomes quite warm, which in turn saves energy. The combination of these things, aswell as the fact that in some areas, electricity is cheaper at certain times of the night leads me to believe they are just as, if not more economical to run.

The big thing for me using baths and rain showers is water pressure, which, unless you're using a very powerful instantaneous heater, which in turn needs a very powerful constant pressure pump behind it, therefore consuming much more energy, will never be able to match an immersion in terms of output.

My house will have 3 of us showering at least twice everyday, maybe baths twice a week, plus washing dishes, and I will defo be using the system I spoke of. Bear in mind, we won't be using hot all Year round - where I am, certain times of the Year are very cold, aswell as very hot.

I've installed 12kw heaters for a couple of laundries, instant 60 degree water - but still not a fast flow rate, and very juicy. Filling a bath with hot water will take a long time with an instantaneous heater, and use a large amount of energy, of which the applicable thermal properties of can't be recaptured to any degree.

Happy bathing !

Edited May 18, 2013 by Ackybang

[Ackybang]

Mike45 asked :

What type of pipe do you use for the hot water in the house?

Hi Mike45 - several options here :-

Many guages of steel, on which you can have the threads turned for you.

Steel pipes and fittings lined with plastic to inhibit rust are available.

Copper with most of the fittings are available here now - I just haven't seen the pre soldered ones, or normal blowtorches, other than for catering use.

I would lag all of the above, and use threadseal on all the fittings - could get away with ptfe on exposed fittings, but not totally reliable with hot water...

I saw black pvc coming into play a good few Years back, but heard it wasn't so reliable, fitting wise - from guys that had used it..

For my build, I'm considering using the more modern green pipe - much easier / cleaner to use - lots of fittings available, all seem good quality with gaskets - only downside is the welder is quite costly - around 3,000 baht - but probably quite a good investment, as it will last 'forever', and can always be sold to a trady, if you didn't want to keep it, I reckon. I've heard very good reports of it, sofar, aswell as some skepticism, but want to see for myself.

I won't be burying or chasing any pipework into walls, and plastering over them. I'll be coming up through the floors, or through the walls from outside with only solid sections of pipe, so no potentially leaking elbows from cold and hot to be hacking walls to pieces to get to in later Years.

What do you use yourself ?

[Mike45]

Mike45 asked :

What type of pipe do you use for the hot water in the house?

Hi Mike45 - several options here :-

Many guages of steel, on which you can have the threads turned for you.

Steel pipes and fittings lined with plastic to inhibit rust are available.

Copper with most of the fittings are available here now - I just haven't seen the pre soldered ones, or normal blowtorches, other than for catering use.

I would lag all of the above, and use threadseal on all the fittings - could get away with ptfe on exposed fittings, but not totally reliable with hot water...

I saw black pvc coming into play a good few Years back, but heard it wasn't so reliable, fitting wise - from guys that had used it..

For my build, I'm considering using the more modern green pipe - much easier / cleaner to use - lots of fittings available, all seem good quality with gaskets - only downside is the welder is quite costly - around 3,000 baht - but probably quite a good investment, as it will last 'forever', and can always be sold to a trady, if you didn't want to keep it, I reckon. I've heard very good reports of it, sofar, aswell as some skepticism, but want to see for myself.

I won't be burying or chasing any pipework into walls, and plastering over them. I'll be coming up through the floors, or through the walls from outside with only solid sections of pipe, so no potentially leaking elbows from cold and hot to be hacking walls to pieces to get to in later Years.

What do you use yourself ?

My experience has been in the states. Copper is the what we use. Soldered copper fittings and the system will last a lifetime.

I'm looking at the green pipe as well- PPV-R I think it is called. The snap on fittings have many complaints on the Internet so for me the welding machine for sure.

I'm also looking at a gas hot water heater. It cost less for gas and it can deliver the volume and heat necessary for whatever your needs. This Spa series Sakura is what I'm using now and it's the best and most economical heater I've ever owned.

http://www.sakura.com.tw/en/product_list.asp

[reflectionx]

Do they have/use PEX piping in Thailand?

I think 99% of the new housing in North America uses PEX.

[mogandave]

The blue PVC works fine for hot water.

[reflectionx]

So I did some research and decided that the tankless heaters that are sold in Thailand won't do the trick. Even the 12kw models provide only about 3 litres / minute at 60 degrees (6litres at 38 degrees), whereas only the rain shower requires 9 litres.

Ideally, I would need the Stiebel Eltron Tempra models, but I cannot find them in Thailand.

http://www.homedepot.com/p/Stiebel-Eltron-Tempra-36-Plus-7-0-GPM-36-0-kW-Whole-House-Tankless-Electric-Water-Heater-Tempra-36-Plus/203210876#.UZ2rOrW3_Ak

This monster can provide 26 litres at 38 degrees!

So, I decided to go the conventional way. Questions:

1. Size. In North America, 40 gallon (150 litres) is considered small. Normally, one would install 60g (230 litres) tank. My research showed that in Thailand they sell as small as 30 litres . Is this because it's way hotter in Thailand? What would be the normal size for a family of 4?

2. Brand. Which one? My guts tell me to go with Stiebel Eltron (the PSH series):

http://www.light-and-bath.com/index.php?lay=show&ac=cat_showcat&l=2&cid=51623

3. Placement. Since there is no basement, where would people normally install them? Is it ok if it's outside - e.g. it won't rust?

Danke!

[Ackybang]

Alright reflectionx,

Go with the Stiebel, or Ferroli / Fagor - which ever is cheapest, or offers a freebie / promotion on the day. They will all last for Years. Go with the biggest one you can find - you can always double up if not enough - although you might find one is enough, unless you all need a bath at the same time as washing the dishes - how many bathrooms do you have ?

You could put it under the house if it's raised up - in the roof cavity, or hang it up underneath one of your roof overhangs - usually 1 meter out here. Rust is unlikely to be an issue, if you put it up high enough - or perhaps hang a cover in front of it, or even build a cupboard around it if you're worried.. You could put it in a garage or shed or pump house equally as well, as long as you dont have it too far away from the house. If you're hanging it, make sure the wall is well rendered in that area, and use expansion bolts if it's redbrick - if it's a breeze, or lightweight 'block' wall, you might have to drill right through it, and put very long nuts and bolts right through with metal strips as a brace on the other side, to take / spread the weight properly.

Ambient water temperature is high here, and most of the Year you would want cold showers, probably. You probably won't be having piping hot showers - your heater is only to take the edge off, if you experience cold spells, or have aircon blasting out, and therefore will keep the water relatively hot, even with the introduction of fresh supply for a good while, as you'll be mixing at a fairly small ratio. Make sure you get a decent high powered constant pressure / inverter pump, for a great rain shower experience - you'll get good constant pressure from both hot and cold supplies, even if there are several other taps open, toilets flushing and you had the washing machine on in your house at the same time. Your immersion can put out as many liters per minute as you can pump into it - (your only restriction would be your pipework guage) - certainly more than 3.

Good luck.

[klikster]

This might be worth a read >> http://www.greenbuildingadvisor.com/blogs/dept/musings/are-tankless-water-heaters-waste-money

[klikster]

FWIW, "Lucky Flame" in Bangkok distributes Rinnai. Wife talked to them yesterday and they have a 16 l/m tankless lpg water heater at about Bt 30,000. II will use that one on our house currently under construction.

[klikster]

FWIW, "Lucky Flame" in Bangkok distributes Rinnai. Wife talked to them yesterday and they have a 16 l/m tankless lpg water heater at about Bt 30,000. I will use that one on our house currently under construction.

They also have 26 l/m and 36 l/m

[jbrain]

FWIW, "Lucky Flame" in Bangkok distributes Rinnai. Wife talked to them yesterday and they have a 16 l/m tankless lpg water heater at about Bt 30,000. II will use that one on our house currently under construction.

That's a lot of money you need to save on electric before you have recovered the premium you paid over an electric tankless heater.

[klikster]

FWIW, "Lucky Flame" in Bangkok distributes Rinnai. Wife talked to them yesterday and they have a 16 l/m tankless lpg water heater at about Bt 30,000. II will use that one on our house currently under construction.

That's a lot of money you need to save on electric before you have recovered the premium you paid over an electric tankless heater.

In my case it's less about the initial cost of the unit and more about getting the kind of hot water service I want. A 21 kw Siemens at InvadeIt is Bt 19K and requires 3 phase power. And the rating seems to be 10 l/m. If I only wanted 5 l/m (abour 8 kw equivalent) I could buy a Mazuma gas for about Bt 5 - 6 K

[Crossy]

Some massive water heaters being proposed here, is someone confusing ^oC and ^oF?

Assuming I've done my sums right (a long time since I did thermodynamics at Uni.), then:

A 12kW heater will give you a 60^oC RISE in water temperature at 3l/M (a temperature which will take your skin off).

If you want to shower at 10 l/M and 40^oC (very hot) with incoming water at 25^oC (cool for most of Thailand) then a 10kW heater will do the job just fine.

Jacking up the flow to 20 l/M then the 21kW unit will be required, but that seems huge flow rate for a shower.

[JAS21]

We live only a few Kms from a pumping station and never need to run our water pump. I have just checked the upstairs shower flow and it's just over 10L/min (29C),we find that flow really adequate but the water just a little too warm .

Now we have a 6Kw heater but it's only ever used and that is by me, on the coldest of days and only then to take the chill off, the rest of the time we find the water from the mains just okay or even too warm.

We have a bath, came with the house, but it's never used. Its only been filled once and that was to make sure nothing leaked. Neither my wife or step-daughter would ever dream of taking a hot shower, I must admit though that I had to put a heater in the guest bathroom as friends came over from the UK one December and complained that the water was a little cold for them!

I suppose that if you are taking water from a well it could also be a little chilly at times. Years ago, when I first came to live here, I took hot showers, same as I did back in the UK ... soon learnt that it's not the best thing to do in a hot country.