Shower water heater

[SOM LUCK]

I have recently installed a 3500 watt water heater at home and am not satisfied with its performance.  With the temp gauge turned to maximum, I must reduce water flow drastically to get just warm water. Installer claimed this was normal performance.  Has anybody had a similar problem.

[mahdam]

I have recently installed a 3500 watt water heater at home and am not satisfied with its performance.  With the temp gauge turned to maximum, I must reduce water flow drastically to get just warm water. Installer claimed this was normal performance.  Has anybody had a similar problem.

I think the guy is probably right. An 8/9 Kw model would have been a better bet I reckon.
I fitted a 9Kw in our bathroom last year, and it works a treat.
Not sure where your water is coming from, but the ambient temperature of it will also affect it's performance.
I also have a 9Kw here in the UK and currently the water coming in is bloody cold.
It copes with this no problem.

[Prakhonchai Nick]

I have recently installed a 3500 watt water heater at home and am not satisfied with its performance.  With the temp gauge turned to maximum, I must reduce water flow drastically to get just warm water. Installer claimed this was normal performance.  Has anybody had a similar problem.

Depends on 2 things. 1) the ambient temperature of the water entering the heater and 2 the water pressure.

My upstairs water heater  supplies less hot water when turned to maximum that the downsatairs one where the pressure is significantly higher..

[mahdam]

I have recently installed a 3500 watt water heater at home and am not satisfied with its performance.  With the temp gauge turned to maximum, I must reduce water flow drastically to get just warm water. Installer claimed this was normal performance.  Has anybody had a similar problem.

Depends on 2 things. 1) the ambient temperature of the water entering the heater and 2 the water pressure.

My upstairs water heater  supplies less hot water when turned to maximum that the downsatairs one where the pressure is significantly higher..

Are both of your shower heaters of the same power capacity Nick?
If so then you would expect to see the opposite of the results you quote.
The slower the water passes over the heat exchanger, then the the more time it will have to heat up.
Push the water past the exchanger faster, then the less time it has to heat up.
If you want hot water at a good pressure, then you have to increase the power output of the element in the exchanger. Som Luck said in the OP that he had reduced the flow in an effort to raise the water temp, but to little effect. This is why I think the low power output of his shower unit is to low to do the job effectively.

[Prakhonchai Nick]

I have recently installed a 3500 watt water heater at home and am not satisfied with its performance.  With the temp gauge turned to maximum, I must reduce water flow drastically to get just warm water. Installer claimed this was normal performance.  Has anybody had a similar problem.

Depends on 2 things. 1) the ambient temperature of the water entering the heater and 2 the water pressure.

My upstairs water heater  supplies less hot water when turned to maximum that the downsatairs one where the pressure is significantly higher..

Are both of your shower heaters of the same power capacity Nick?
If so then you would expect to see the opposite of the results you quote.
The slower the water passes over the heat exchanger, then the the more time it will have to heat up.
Push the water past the exchanger faster, then the less time it has to heat up.
If you want hot water at a good pressure, then you have to increase the power output of the element in the exchanger. Som Luck said in the OP that he had reduced the flow in an effort to raise the water temp, but to little effect. This is why I think the low power output of his shower unit is to low to do the job effectively.

Oops  correct Mahdam....Started on the amber liquid somewhat earlier today

[mahdam]

 

I have recently installed a 3500 watt water heater at home and am not satisfied with its performance.  With the temp gauge turned to maximum, I must reduce water flow drastically to get just warm water. Installer claimed this was normal performance.  Has anybody had a similar problem.

Depends on 2 things. 1) the ambient temperature of the water entering the heater and 2 the water pressure.

My upstairs water heater  supplies less hot water when turned to maximum that the downsatairs one where the pressure is significantly higher..

Are both of your shower heaters of the same power capacity Nick?
If so then you would expect to see the opposite of the results you quote.
The slower the water passes over the heat exchanger, then the the more time it will have to heat up.
Push the water past the exchanger faster, then the less time it has to heat up.
If you want hot water at a good pressure, then you have to increase the power output of the element in the exchanger. Som Luck said in the OP that he had reduced the flow in an effort to raise the water temp, but to little effect. This is why I think the low power output of his shower unit is to low to do the job effectively.

Oops  correct Mahdam....Started on the amber liquid somewhat earlier today

  Well done Nick, nothing changed then?
We are flying back next week, and hope to bump into you  for a chin wag sometime.
In the meantime, wishing you and your family all the very best for a happy and healthy New Year
From Lek and I.

[Prakhonchai Nick]

I have recently installed a 3500 watt water heater at home and am not satisfied with its performance.  With the temp gauge turned to maximum, I must reduce water flow drastically to get just warm water. Installer claimed this was normal performance.  Has anybody had a similar problem.

Depends on 2 things. 1) the ambient temperature of the water entering the heater and 2 the water pressure.

My upstairs water heater  supplies less hot water when turned to maximum that the downsatairs one where the pressure is significantly higher..

Are both of your shower heaters of the same power capacity Nick?
If so then you would expect to see the opposite of the results you quote.
The slower the water passes over the heat exchanger, then the the more time it will have to heat up.
Push the water past the exchanger faster, then the less time it has to heat up.
If you want hot water at a good pressure, then you have to increase the power output of the element in the exchanger. Som Luck said in the OP that he had reduced the flow in an effort to raise the water temp, but to little effect. This is why I think the low power output of his shower unit is to low to do the job effectively.

Oops  correct Mahdam....Started on the amber liquid somewhat earlier today

  Well done Nick, nothing changed then?
We are flying back next week, and hope to bump into you  for a chin wag sometime.
In the meantime, wishing you and your family all the very best for a happy and healthy New Year
From Lek and I.

Early return - or is that arrival? Depends of course where you are now . Take care and very best wishes to you and Lek for the New Year from Dow & I

[fishy]

I'm using an 8,000 watt system and have to mix cold water with it to cool it down.. I can just handle getting into the jacuzzi without adding cold water.. The missus has to wait for it to cool before she can climb in.... I had a sheeeet fight with electrics and idiots installing it. The golliwogs who installed it had never put a unit in bigger than 3,500 watts before... Don't mention the war!!!

[Thai Bart]

Hi Som Luck, 3.5 Kw for this time of year is very borderline. As others have said it will depend upon water temp and delivered pressure. The boiler in these units is very small and the water is inside it for a very short time but I will guess in the warmer months it would be acceptable to you. I have just tried a 4.5 Kw unit and the water temp coming in is quite cool and supplied from an electric pump and it is only set at about 1/3 of the total scale and is nicely warm. I know this is of no help to you as you have a 3.5 Kw unit but just to let you know that a 4.5 Kw unit is adequate for these weather conditions. Our main units are 5.5 Kw and they are only ever set to 2/3 rds full scale even on the coldest of days.
You say they are recent, do you know if you have hard water ( limescale probs eg white deposits once the water dries ) It really doesn't take long for a boiler in anything to " scale " up if you have hard water. It sticks all over the heater element and drastically reduces it efficiency.
Sorry you should buy something with a higher Kw rating.
Bart

[SOM LUCK]

thanks bart

[iammike]

Please also check, when changing a 3.5Kw water heater for a higher rated one, that your wiring and breaker is adequate as you don?t want your breaker trip when you take a shower or worse an electrical fire.

[SOM LUCK]

thanks Mike

[Thai Bart]

Hi Som Luck, I meant to add what Iammike has written, if you do decide to uprate your shower then you will most likely need it re wired unless by some miracle they used 6 mm cable on the original install. That is based on a 5.5/6 Kw shower, breaker needed 30/32 amp depending on what fuseboard you have and what size breaker they make for it. 4 mm should be ok for a 4.5 Kw for safety reasons, provided its not buried in the wall for 60 Meters. Enclosure under plaster down rates the cables current carrying capacity. Breaker size is tricky as the current is marginally over 20 amps assuming voltage at 220V.

This morning I checked with a thermometer the water temp and it was 21 degs C and my 5.5 Kw was ok but I did have to turn it to full. If I throttled back the water pressure a little bit then it was slightly too hot at full power. Again it isn't much help for your problem but 5.5 Kw was sufficient for me. I used to have a 6 Kw in the U.K and the incoming water was much colder than here in the winter.
Bart.

[iammike]

+1 @Bart.

One thing you also have to check @Som Luck.

Which type of Electric Meter you have hanging outside.

There (AFAIK) 3 types in Thailand (someone correct me if I am wrong)

5-15amp, 15-45amp and 30-100amp

if you only have 5-15amp. You will need to ask the PEA for an upgrade of your meter if you want to get a bigger Water Heater.

[Thai Bart]

+1 @ iammike, a very good point and one that I would not have thought of until it blew to bits