Hot Cold Water Mixer Tap And 8000W Instant Heater

[klikster]

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.

I'm not proposing anything. Just passing on some sourcing information that a number of folks have asked about in the past -- like where they can get good LPG heaters that can handle an entire house. Nor am I confusing C & F.

When the weather gets cold, I like a strong hot shower. When the weather is warm, I like a strong cool shower. These small electric units seem to reduce flow too much for me, and apparently a rain shower needs something on the order of +/- 6 l/m.

Also will have a bathtub, plus want hot water in the bath sink and kitchen sink .. and sometimes use in washing machine.

[Mike45]

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.

I'm not proposing anything. Just passing on some sourcing information that a number of folks have asked about in the past -- like where they can get good LPG heaters that can handle an entire house. Nor am I confusing C & F.

When the weather gets cold, I like a strong hot shower. When the weather is warm, I like a strong cool shower. These small electric units seem to reduce flow too much for me, and apparently a rain shower needs something on the order of +/- 6 l/m.

Also will have a bathtub, plus want hot water in the bath sink and kitchen sink .. and sometimes use in washing machine.

Klikster

What will you use for piping for the hot water?

Thanks

[klikster]

^^ My house is 1 floor with a 3 m wide terrace running across the back of the house. I plan to locate the unit on the terrace next to the master bath which shares a wall with the kitchen. So I am thinking to use copper off the heater and maybe high temp PVC for longer runs.

[Mike45]

^^ My house is 1 floor with a 3 m wide terrace running across the back of the house. I plan to locate the unit on the terrace next to the master bath which shares a wall with the kitchen. So I am thinking to use copper off the heater and maybe high temp PVC for longer runs.

I have a 16L gas hot water heater in Taipei that supplies my entire 3 bed 2 bath condo. Rain shower/ bath tub/ sinks/ dishwasher / washing machine. It does everything I want and more at high volume levels.

I guess the PPR WELDED piping should work well. There click to fit look like a real potential headache.

Ubon gas and Ubon Makro called for us to Rinnai in Bangkok and was told they no longer import the gas models. I would appreciate it if you would Please update when you have successfully bought yours with the tel number and contacts name.

I think to get the water volume we desire we will need a larger pump. I'm think of a 350w or 400w.

What are you planning for a pump?

[sotsira]

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

If your concerned with the hot & cold water mix in the shower valve then the solution is to

fit a thermostatic shower valve.

Grohe are the leading brand for these.

Here's a link:

http://www.grohe.com/ie/4756/bathroom/shower-thermostats/

[reflectionx]

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.

Some of your math is good, some is flawed. You are right that 12Kw will give you 3-4l/min at about 60C.

However, no 10Kw heater will provide 10l/m at 40C. Most tankless have "maximum" flow rate. For example, even the 12Kw Siemens DH12103 has max rate of 6.5l:

http://www.siemens-home.com/ae/product-showroom/small-appliances/water-heater/DH12103.html

You need 9l/min for good rain shower experience. If you add bath tub, wash basin, etc, you will need at least one per bathroom.

Also, there is a problem with long piping and tankless heaters.

In my case, I have 3 bathrooms to pipe (3 rain showers, 3 sinks, one tub) + kitchen faucet. The cost of 100l conventional water heater is less than the cost of the 12Kw Siemens unit, of which I would need at least 3. Easy decision for someone who needs lots of juice.

If you are in a condo, however, and have only one shower, tankless would make perfect sense.

[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

If your concerned with the hot & cold water mix in the shower valve then the solution is to

fit a thermostatic shower valve.

Grohe are the leading brand for these.

Here's a link:

http://www.grohe.com/ie/4756/bathroom/shower-thermostats/

Yup,

Got me Hansgrohe Ecostat 1001 for less than 100 euro on fleebay

[klikster]

"Ubon gas and Ubon Makro called for us to Rinnai in Bangkok and was told they no longer import the gas models. I would appreciate it if you would Please update when you have successfully bought yours with the tel number and contacts name."

Wife contacted "Lucky Flame" in BKK.

[reflectionx]

Does anyone know someone who can install PPR pipes in Krabi?

Also, a plumbing shop in Phuket quoted for the pipes alone:

1/2 inch (4m>216thb)
3/4 inch (4m>332thb)

It seems a more expensive than my expectnations - was expecting less than $1/m for the 1/2", no?

[klikster]

> reflectionx

After reading your post above I'm starting to rethink my hot water system. Do you recommend a hot water tank style heater over a gas tankless?

Are you talking about a gas fired tank style or an electric tank style? Outdoors on the terrace? I can see advantages and disadvantages for tank style.

[reflectionx]

> reflectionx

After reading your post above I'm starting to rethink my hot water system. Do you recommend a hot water tank style heater over a gas tankless?

Are you talking about a gas fired tank style or an electric tank style? Outdoors on the terrace? I can see advantages and disadvantages for tank style.

I guess it depends on your situation. I need to equip 3 bathrooms and kitchen, so I need lots of juice. It took me a while to figure it out, but I think given my situation the choice is clear to me.

I've only researched electric heaters, as the gas ones are 3-4 times more expensive. Moreover, a kid could maintain/repair/replace electric heater, whereas gas heater needs to be repaired/replaced by technician. With expected lifetime of 10-15 years of tank style heater, IMHO the savings from gas over electricity do not justify the difference in ownership cost.

Again, if you are living in a small condo with one bathroom, tankless is probably the better way to go.

My main problem is that I am trying to come up with "North American/European" style installation that I won't have to deal with for 25+ years. Our builder is very experienced in Thai style construction, but not so much when it comes to western style. From what I've gathered so far, if you want the job done it the western way, you should look for a builder involved in commercial construction - hotels, etc.

I will give an example. Our builder had to install PPR pipes once, and when we asked him how he joint the pipes, he said that he'd used the same glue he used for PVC. BUMMER !!! He had no idea that they have to be welded. But when we called the plumbing store, they said that usually hotels buy PPR piping, which makes me think that commercial contructors know how lay PPR.

As for the mounting, I plan to buy the Stiebel PSH (80 or 100) and mount it on an outside wall (in case it ever leaks, I wouldn't care). They are considered wall mountable:

The only issue I am worried about for exterior installation is rusting, but worst case I will come up with some sort of a plastic shelter to protect from rain.

[Mike45]

> reflectionx

After reading your post above I'm starting to rethink my hot water system. Do you recommend a hot water tank style heater over a gas tankless?

Are you talking about a gas fired tank style or an electric tank style? Outdoors on the terrace? I can see advantages and disadvantages for tank style.

I guess it depends on your situation. I need to equip 3 bathrooms and kitchen, so I need lots of juice. It took me a while to figure it out, but I think given my situation the choice is clear to me.

I've only researched electric heaters, as the gas ones are 3-4 times more expensive. Moreover, a kid could maintain/repair/replace electric heater, whereas gas heater needs to be repaired/replaced by technician. With expected lifetime of 10-15 years of tank style heater, IMHO the savings from gas over electricity do not justify the difference in ownership cost.

Again, if you are living in a small condo with one bathroom, tankless is probably the better way to go.

My main problem is that I am trying to come up with "North American/European" style installation that I won't have to deal with for 25+ years. Our builder is very experienced in Thai style construction, but not so much when it comes to western style. From what I've gathered so far, if you want the job done it the western way, you should look for a builder involved in commercial construction - hotels, etc.

I will give an example. Our builder had to install PPR pipes once, and when we asked him how he joint the pipes, he said that he'd used the same glue he used for PVC. BUMMER !!! He had no idea that they have to be welded. But when we called the plumbing store, they said that usually hotels buy PPR piping, which makes me think that commercial contructors know how lay PPR.

As for the mounting, I plan to buy the Stiebel PSH (80 or 100) and mount it on an outside wall (in case it ever leaks, I wouldn't care). They are considered wall mountable:

The only issue I am worried about for exterior installation is rusting, but worst case I will come up with some sort of a plastic shelter to protect from rain.

I've had hot water tanks usually in the 40 to 50 Gallon capacity. I've never had one last more than eight years and that's inside the house and with replacing the sacrificial anode every two years. Do the stiebel have a sacrificial anode? Electric has a very slow recovery rate gas is much better for quick recovery.

How expensive is the Stiebel and do they have gas units like it?

Thanks Mike

[reflectionx]

I've had hot water tanks usually in the 40 to 50 Gallon capacity. I've never had one last more than eight years and that's inside the house and with replacing the sacrificial anode every two years. Do the stiebel have a sacrificial anode? Electric has a very slow recovery rate gas is much better for quick recovery.

How expensive is the Stiebel and do they have gas units like it?

Thanks Mike

Well, in Europe these sell with 10 years warranty. Can't find much info in Thailand. This site is in Bulgarian, and you will see next to the Stiebel logo another image that states "10 години гаранция", meaning 10 years warranty:

http://translate.google.ca/translate?sl=bg&tl=en&js=n&prev=_t&hl=en&ie=UTF-8&eotf=1&u=http%3A%2F%2Fwww.balmax.com%2Frub.php%3Fsr%3D1%26r%3D31%26r1%3D57&act=url

According to the website, the anode is magnesium.

My experience with tank heater is that they usuailly last about 10 years. But this is in North America, maybe those Stiebels are better quality? It also depends on the water quality. However, it's a piece of cake to perform maintenance on these babies. And when time comes, I can change it myself.

Don't know about gas heaters, but I am almost positive that the life expectancy would be the same as the electric ones. So in 10 years, you will have to pay again 3 times more for heater + installation.

[reflectionx]

Actually, gas heaters have less life expectancy:

http://hotwater.ca/gas-vs-electric

[Mike45]

Actually, gas heaters have less life expectancy:

http://hotwater.ca/gas-vs-electric

Personally I love the idea of a hot water tank but I'm really not sure about the products your describing because they are unknown to me. If I could get an American type 40 gallon gas water heater I would be thrilled.

The problem I see is a slow recovery rate with the smaller than I am accustomed to electric tanks. The Stiebel 80 liter that you mentioned earlier will have a capacity of 21 gallons and a recovery rate of 7 gallons per hour. That's not enough hot water capacity and a very slow recovery rate. I do not think any of us would Be happy with this product.

[reflectionx]

Actually, gas heaters have less life expectancy:

http://hotwater.ca/gas-vs-electric

Personally I love the idea of a hot water tank but I'm really not sure about the products your describing because they are unknown to me. If I could get an American type 40 gallon gas water heater I would be thrilled.

The problem I see is a slow recovery rate with the smaller than I am accustomed to electric tanks. The Stiebel 80 liter that you mentioned earlier will have a capacity of 21 gallons and a recovery rate of 7 gallons per hour. That's not enough hot water capacity and a very slow recovery rate. I do not think any of us would Be happy with this product.

Get the PSH 150 then as it's roughly 40 gallons.

Don't forget that the cold water and the ambient temperature in Thailand are much higher then in North America, so you will be using less hot water.

I've never measured the tap water temperature, but when I drink water, it feels like I just took it out from the fridge. I'd say probably around 10 Celsius. And even when we had 40 gallon tank, we never run out of hot water.

[klikster]

"Personally I love the idea of a hot water tank but I'm really not sure about the products your describing because they are unknown to me. If I could get an American type 40 gallon gas water heater I would be thrilled."

Me too! Are these simply not available in Thailand?

I too am concerned about the recovery rate for electric heaters -- even the Fagor (Invadeit.com) 250l @ 3kw. What should be the recovery on that unit?

Seems to me the problems is not the warm days in May down in Krabi -- but the cold nights of Dec/Jan here in Isaan.

[Crossy]

I too am concerned about the recovery rate for electric heaters -- even the Fagor (Invadeit.com) 250l @ 3kw. What should be the recovery on that unit?

Once again, if my maths is correct, a 250l 3kW tank will recover at about 10^oC per hour from whatever temperature it decays to when drawn down.

This assumes that it will be an event temperature throughout.

It will actually be slightly better than that as the tank will stratify with hot at the top (where the draw off is) and cool at the bottom (where the inlet is).

[Mike45]

"Personally I love the idea of a hot water tank but I'm really not sure about the products your describing because they are unknown to me. If I could get an American type 40 gallon gas water heater I would be thrilled."

Me too! Are these simply not available in Thailand?

I too am concerned about the recovery rate for electric heaters -- even the Fagor (Invadeit.com) 250l @ 3kw. What should be the recovery on that unit?

Seems to me the problems is not the warm days in May down in Krabi -- but the cold nights of Dec/Jan here in Isaan.

http://hotwater.ca/gas-vs-electric

Look here for recovery rates.

[reflectionx]

Btw, some useful discussion on hot (and cold) water piping here:

http://www.thaivisa.com/forum/topic/644323-ppr-piping-in-krabi/

[Greenside]

Something I don't see much mention of in this discussion is the issue of pipe run when using a conventional hot water tank. We have a 120L tank in our present house and placed it on the outside wall under the eaves equidistant between the one bathroom and the kitchen - a matter of only about 5m each way. It is switched on for 2 periods of 2 hours a day and provides sufficient hot water for a family of three (power consumption is 8kWh per day as it's on the middle setting) but from either the bathroom or the kitchen it's still 30 - 40 seconds for the hot water to make it to the tap. In practice what this means is that you don't use hot water unless you really need to - no bad thing in itself but it also means quite a lot of water is left in the pipe when you have finished using it which is a waste.

Our new house has three areas that require hot water - one with two nearby bathrooms, a second with two kitchens and a third with a guest bathroom and although I would have liked to use a single tank, the locations are so far away that you'd grow old while waiting for the water to reach you, even with a centrally placed tank. We had decided to go with multi-point instant heaters but that was when I was assured that there were no problems with mixer taps and flow rate and now I'm not so confident! Incidentally, our new house is in Chiang Mai and progress is being documented in a forum I can't name here but has something to do with the temperature of houses in Thailand.

[reflectionx]

Something I don't see much mention of in this discussion is the issue of pipe run when using a conventional hot water tank. We have a 120L tank in our present house and placed it on the outside wall under the eaves equidistant between the one bathroom and the kitchen - a matter of only about 5m each way. It is switched on for 2 periods of 2 hours a day and provides sufficient hot water for a family of three (power consumption is 8kWh per day as it's on the middle setting) but from either the bathroom or the kitchen it's still 30 - 40 seconds for the hot water to make it to the tap. In practice what this means is that you don't use hot water unless you really need to - no bad thing in itself but it also means quite a lot of water is left in the pipe when you have finished using it which is a waste.

Our new house has three areas that require hot water - one with two nearby bathrooms, a second with two kitchens and a third with a guest bathroom and although I would have liked to use a single tank, the locations are so far away that you'd grow old while waiting for the water to reach you, even with a centrally placed tank. We had decided to go with multi-point instant heaters but that was when I was assured that there were no problems with mixer taps and flow rate and now I'm not so confident! Incidentally, our new house is in Chiang Mai and progress is being documented in a forum I can't name here but has something to do with the temperature of houses in Thailand.

I am talking to someone from the company importing the pimaflex (Pert-Al-Pert) pipe, he just mentioned that they offer some high volume tankless heaters. I will keep you posted

[Mike45]

Btw, some useful discussion on hot (and cold) water piping here:

http://www.thaivisa.com/forum/topic/644323-ppr-piping-in-krabi/

Very interesting!

[klikster]

I got a recent email from a Rheem dealer in Singapore. They tell me that 'Mex' sells a Rheem tankless gas heater under their own brand

[reflectionx]

Ok, got the link for the tankless water heaters:

http://www.hydlon.com/en/our-products/water-heating-system.html

They are also antibacterial and can be controlled via Internet. Pretty neat.

3 models:

40 deg C at Flow 6-9 litre/minute

48 deg C at Flow 13 litre/min

ที่อุณหภูมิ 53 องศาเซลเซียส ปริมาณน้ำ 24-40 ลิตร ต่อนาที (Temperature 53 ° C, 24 to 40 liters of water per minute)

Will get back with pricing details

[Greenside]

I can't find any independent reviews of these products and the language and presentation brings to mind the myriad fuel and energy saving products available but for the most part discredited. If this can really save 50% and do all the things they claim wouldn't we know about it or a competitor by now? Not to be too cynical, but I've had a "friend" try to flog me an investment in hydrogen converters for motorbikes for more than 5 years now and he still can't show me one that works. Somehow the model that runs without a regular gas tank on board is always a few months away...

If it really works, I'm interested

Edited June 19, 2013 by Greenside

[Crossy]

The numbers on the Hydlon site just don't add up.

The V2.1.2219 unit which claims 48^oC @ 13 Litres / minute consumes 33kW (150A @ 220V, rather more than any local domestic single phase supply can handle anyway).

The laws of thermodynamics mean that 33kW will heat 13 Litres / minute to a delta-t of 36.2^oC IF the heater is 100% efficient, that's far short of 48^oC, these heaters must be more than 100% efficient!

An extra 10kW is coming from somewhere, or are the figures simply misleading and quoting an output temperature rather than a delta-t? With an inlet temperature of 20^oC it would easily attain an output of 48^oC

[reflectionx]

The numbers on the Hydlon site just don't add up.

The V2.1.2219 unit which claims 48^oC @ 13 Litres / minute consumes 33kW (150A @ 220V, rather more than any local domestic single phase supply can handle anyway).

The laws of thermodynamics mean that 33kW will heat 13 Litres / minute to a delta-t of 36.2^oC IF the heater is 100% efficient, that's far short of 48^oC, these heaters must be more than 100% efficient!

An extra 10kW is coming from somewhere, or are the figures simply misleading and quoting an output temperature rather than a delta-t? With an inlet temperature of 20^oC it would easily attain an output of 48^oC

I think it's output temperature, not delta. However, heat pumps are more than 100% percent efficient (depending on the outside temperatures), so it would be possible that a heater is more than 100% efficient. I am not saying that this is the case, but it would be possible. Electric furnace is more or less 100% efficient (I think modern gas furnaces are about 90-95%), whereas Zuba, for example, can be up to 3 times more efficient than a furnce.

From I've gathered so far, V2 goes for about 23k baht, they come with 5 yrs warranty on the steel, 2 yrs on electronics. If the performance they claim is more or less accurate, I think it might worth looking into it. For me the most important parameter is the maxim water flow rate, which was the main reason for me to ditch the tankless (max flow of 6L/m is a joke to feed the entire place). Is this baby achieves 13L at 48, it would give me more than 20L at 38, which would be enough for 2 rain showers at the same time.

I will post if get some more detailed info. Their website is a joke.

[Crossy]

Heat pumps are NOT more than 100% efficient, they can output more heat than the electricity supplied, but that heat comes from the cold side getting colder.

A 10kW state-change heat pump is the equivalent of a 34,000 BTU aircon.

If it's a heat pump it's not state-change it must be Peltier, a 10kW Peltier?

[reflectionx]

Heat pumps are NOT more than 100% efficient, they can output more heat than the electricity supplied, but that heat comes from the cold side getting colder.

A 10kW state-change heat pump is the equivalent of a 34,000 BTU aircon.

If it's a heat pump it's not state-change it must be Peltier, a 10kW Peltier?

LOL, I am not an engineer, so I can't answer your questions

But from purely mathematical point of view - if the output > input, it's more than 100%