In-tank "resistance" element water heaters - beware

[dngood]

Having changed our solar system in October last year to a Sunmax tubular system which can take an in-tank "resistance" water heater, we were well aware that the element wouldn't last very long with the high lime scale content of the water. We were diligently advised to get an Italian made element for around 70TL, and ensure we put Calgon in the tank.

So, just over 100 days later, and about 200 hours of being turned on (the element is probably turned on about 2 hours per day) - we notice that the water's cold, and we're getting minor "electric shocks" when we touch the taps. So we call them out, and the 100 day old element is rusty and burnt through in 2 places which you can see here:

Was it replaced under any form of guarantee or apology? Of course not, even after heated discussions and an abrupt and dismissive phonecall "Only the solar system is guaranteed, no company in the world would guarantee anything mixing electric and water".

Beware.

Dave.

 

[juco]

I am not an electrician but......


That looks like a cheap and nasty element, maybe they all look like that.
if you take areas in UK with high limescale the heaters last for years, how come, I dont know but begs the question.

Has your tank ever run dry? that could cause it to burn out.

If limescale causes the problem there seems to be a lack of it on the element.

Scary though. Might be worth googling to see if you can get some answers.

 

[dngood]

Has your tank ever run dry? that could cause it to burn out.

If limescale causes the problem there seems to be a lack of it on the element.

Thanks for the suggestions; No, it's never run dry - at least not that we know (we have a large cold water tank).

BTW, I think if I scraped away the crap it'd say "made in Turkey" on it.

Dave.

 

[Gazgaskell]

Looks very much like your average 15 lira immersion heater, (su resistance) which if you are lucky can last up to a year! I seem to replace ours on a regular basis & its a straightforward job for any handyman & you get so good at changing these that you don't even need to turn the water off if you are quick! As mentioned by Juco there doesn't seem to be any limescale on it.

Sadly the advice for an 'Italian element' was your typical 'tradesman' ruse to get you to pay over the odds! Find someone local you can trust to fit new thermostat, top price inc labour up to 40-50TL inc parts

Gaz

 

[dngood]

Thanks, well at least I know it's another company not to bother using! It's a shame; they started with such promise...

 

[yalimart]

I had my sunmax system fitted in november, and had to have the replacement fitted in december, again they said Turkish crap ! we will fit an italian reziztance, it was done under guarantee next morning no questions asked, my plan is to buy one in turkey and then check if they have the the same threading as in the uk, if so i will bring a couple over, I am an electrician and when i change these things in the uk, they are usually 20 to 30 years old, but probably hardly used as the cental heating usually heats the water

martin

 

[mollag]

Just thinking Martin, if they ommited to earth the element do you think the corrosion could be down to electrolytic action, sort of a sacrificial anode?

There are probably no metal pipes so earth potential would be through the water.

 

[dngood]

Martin,

Glad you had a good experience, albeit the same speil!

I believe we have the same Sunmax system, and I now have the old element out of the tank - if you would like me to do any measurements or photos to help you identify a UK equivalent, just let me know; it's no problem.

Dave.

 

[dngood]

Just thinking Martin, if they ommited to earth the element do you think the corrosion could be down to electrolytic action, sort of a sacrificial anode?

There are probably no metal pipes so earth potential would be through the water.

Interesting; I guess that would explain the tingle through the tap we experienced!

 

[mollag]

The tingles might be down to lack of equipotential bonding [ earthing ], but if its down to a live earth fault then you should check you mains board is protected by an RCD [earth trip] if it is, check it works [test button], if not then you would be best to fit one.

 

[perfect1949]

i got one fitted last saturday ,i dont know what type it was but the guy who fitted it said it would last for ages .the cost was 185 tl i will just see how it goes

 

[yalimart]

Just thinking Martin, if they ommited to earth the element do you think the corrosion could be down to electrolytic action, sort of a sacrificial anode?

There are probably no metal pipes so earth potential would be through the water.

hi mollag

the resistive part of element is encased in a powder that conducts heat but not electricity, my guess is it is badly made and looking at where it burnt through about half way along the element, again i can only guess that the full 230 v was not passing through it, probably half of that, what is more worrying is that the rcd didnt trip, i would test this as well.

martin

 

[yalimart]

Martin,

Glad you had a good experience, albeit the same speil!

I believe we have the same Sunmax system, and I now have the old element out of the tank - if you would like me to do any measurements or photos to help you identify a UK equivalent, just let me know; it's no problem.

Dave.

Dave

measure the length of the element from the base to the tip, it looks like 27" from your photo, also measure accross the diameter of the thread, and if you can send me a photo of the electrical connections that would help, including the cover off the top of the element, in turkey they are "waterproof" as they are outside, in the uk they are not as they are inside

martin

 

[dngood]

We have an RCD, and it's certainly tripped at other things, but I'll see if I can get someone (else) to take a look. FWIW, the heater is on a seperate switch.

It outstands me that there seems to be many similar stories, and anyone actually willingly fits these cheap devices, knowing that they're such poor quality. Companies' lack of customer satisfaction and awareness of reputation continue to amaze me.

Dave.

 

[matty]

We had one fitted 8 years ago, cost then 40 lira!..Still working..(Touch wood.)
PS We have never put any Calgon in the tank.

 

[yalimart]

We had one fitted 8 years ago, cost then 40 lira!..Still working..(Touch wood.)
PS We have never put any Calgon in the tank.

i wonder if the new water supply to the bodrum area will make a difference, as it is supposed to be filtered so i am told

martin

 

[mollag]

Hi Martin, know what you mean with a reduced voltage and high current but i was thinking more of non "live" situation.
With the brass ferrule, galvinized tank full of water and poor bonding then you could have a little battery going on here, then again it just might be a crap element!.

Re the earth trip, if it tests ok then yu should be safe, given you had tingles with no tripping it may be your tank/heater isnt earthed.

Had a mate here who had a tripping problem, the sparks told him the ELCB [earth leakage trip] was faulty, he replaced it with a switch which of course didnt trip. The fault was still there waiting to hurt someone and he was left with no protection.
Unless you are 100% certain of your sparks then hunt for an anglo to "assist" you.

 

[dngood]

Dave

measure the length of the element from the base to the tip, it looks like 27" from your photo, also measure accross the diameter of the thread, and if you can send me a photo of the electrical connections that would help, including the cover off the top of the element, in turkey they are "waterproof" as they are outside, in the uk they are not as they are inside

martin

Measurements:

Total length (plastic base to tip): 40cm
Element length (including thread): 36cm
Thread Diameter: 4cm
(2kW, 220V)

I can't get the brown cover off. I'll try again in the morning with a hammer

 

[yalimart]

dave

the cover i meant would go over the electrical connections

martin

 

[yalimart]

Hi Martin, know what you mean with a reduced voltage and high current but i was thinking more of non "live" situation.
With the brass ferrule, galvinized tank full of water and poor bonding then you could have a little battery going on here, then again it just might be a crap element!.

Re the earth trip, if it tests ok then yu should be safe, given you had tingles with no tripping it may be your tank/heater isnt earthed.

Had a mate here who had a tripping problem, the sparks told him the ELCB [earth leakage trip] was faulty, he replaced it with a switch which of course didnt trip. The fault was still there waiting to hurt someone and he was left with no protection.
Unless you are 100% certain of your sparks then hunt for an anglo to "assist" you.

You might have something with the dissimilar metals, and the tank may be stainless on the sunmax system
There is no requirement to supplementary bond or equipotential bond a plastic pipe sytem in the uk so as its Turkey !!!!!

the earth connection in the supply cable should be adequate

martin