Water heater whistles

 My wife and I own a dwelling in Guardamar del Segura and we had our water heater changed 3 years ago. We come here  2 months  every year. From the beginning, the water heater made  loud whistling noises every now and then,  some times every 2 minutes sometimes every hour, unpredictably for varying lenghts of time . We had the plumber who installed it come twice and also the  company that services these heaters. They said it was normal and that the whistling would go away gradually as it wears. Well the whistling seems to be getting worse and now something has to be done.  We always shut it down before we leave the country and  close the main water valve as a safety measure, so the water heater does not  have much time to wear itself. If we call the plumber again, and it doesn’t whistle when he’s here , then he has nothing to work on and we have to pay his fees. The previous water heater never made a sound and worked well for 12 years. Has anyone had this problem  with new water heaters and how did you solve it. Thanks.

Hi william02

I am not a plumber and certainly no expert. However I have experienced 'whistling' in our heaters in the past.

It was mostly always a build up of calcium in the boiler/heat exchanger. So we were told. This was as the result of limescale from the water. It does that as the water heats and deposits in the heat exchanger. So we were told.

I don't know what sort of heater you have, gas or electric? but I think it is more common in gas. Also I do not know what the softness/hardness of the water in your area is. Something to do with the Clarke Scale, we are told. Hard water is more problematic.  Our water is soft but still we had a problem.

The solution for us was on one occasion was a flush to rid the heater of limescale on another the build up was so bad we needed a new boiler. I think by leaving water in the boiler, when you leave, makes the build up worse. Again this is only what we have been told by a plumber/heating engineer. I am no plumber or expert.

Hope this assists. Good Luck.  Mick

Thank you Mick. Your reply was helpful. It is an electric heater, it made the whistling sound from the day it was installed, and from you say about limescale, what I think is that some particles from the old plumbing moved into the new heater and blocked some valves. I think the plumbers should have flushed the plumbing first before the  installation. On the next water heater I will have them install a little faucet so I can empty the tank before we leave. Thanks again.

William02

Our electric tank usually whistles when it's heating the water. (i.e. after using hot water and fresh cold water entering the tank causes the thermostat to kick in.

Certainly calcium / limescale is a big problem where we are. If water is left standing for any time, or taps not used, it can cause damage. I regularly jiggle the valves under sinks and by the WCs etc. to make sure they are still working and not jammed up. I've just replaced a shower mixer tap that hasn't been used for years, because it was broken due to limescale build up. Thankfully, I only had to shut off the water to that bathroom and not the whole apartment, as I would have had to, had those little taps been jammed up with calcium. We had our electric tank (and all pipe lines) cleaned out with acid by an excellent German plumber a few years ago. The chunks of calcium that he got out of the tank and chipped off the element were huge. We're the only owners out of 12 who haven't replaced the tank in 13 years though. Spaniards don't tend to maintain so much as run things into the ground and then replace (like cars)

Thanks Roberto for your reply.The source of our water, in Guardamar, from what I was told, is from a desalination plant. I would suppose that this water should not cause lime scale build up. Does anyone know? As I said in the first post, the previous water heater worked perfectly, soundless for over 12 years, so am I beginning to wonder if it is just a bad installation with something entering the tubing and blocking, or a defective heater they sold us. Roberto has mentionned that his taps tend to jam because of limescale. I just checked a toilet valve I never turned in 16 years, and it turned smoothly. Our water heater doesn't make noise when it is heating,  the noise is similar to a tap that your about to close and whines just before complete closure, except the noise last from 10 to 40 seconds or so each time. Seems like a pressure equilibration of water though a valve that is too tight. I  think we will have the water heater replaced by a different plumber and different brand of heater, similar to the previous one that worked well.

William02

I suspect that you need not worry if your plumber found nothing wrong, especially if you are in a soft water (desalinated) area. Some heaters make a noise some don't.

You have not mentioned the temperature. Nearly all electric water heaters have a temperature control which adjusts the internal thermostat. Sometimes it is accessed by a visible knob but sometimes you have to take the cover off. If the latter turn off the electric supply to the heater before taking the cover off.

Many people in Spain run their heaters far too hot because it is not big enough and there is not enough water in the heater to run a bath or have two showers. Running the heater at a lower temperature often stops the noise when it is caused by the water close to the element boiling. The reason that this noise comes and goes is because the element is switched off when the thermostat measures the water as up to temperature. 

If the noise stops or starts shortly after running a hot tap this is probably the case (the movement of water moves the very hot water away from the element). Try turning the temperature down.

Finally, for those with hard water. Your element will last longer, if the temperature is lower.

tteedd,

Last year I reduced the temperature and it did help, but did not stop it. There are 7 settings, it was at setting 6, I reduced it to 4. I also reduced the debit of water, by partially closing the main water valve, that seemed to help a bit too. If I close the heater's cold water  entry valve, the noise instantly stops, and may stop or start again when I reopen it. If I open the hot water faucet briefly, the noise stops instantly, for a while.  So what you say may apply to my heater. Still the noise is aggravating. I must have one of these  brands of noisy heaters, I will try find a better brand.Thanks for your input.

William02

William 02 have you checked and made sure you have no water Leak's ...to do this all you have to do is make sure all the toilet flush tanks are full and not overflowing check that all the hot and cold taps are turned off throughout the property then go and have a look at your water meter if the dial  is still turning you have got a water leak within the grounds of the property this kind of leak can cause a hissing noise .if you don't have a water leak then tteedd post is spot on good luck.

William. I have just googled   'why do hot water tanks sing'

There is a lot of info available, amongst which you may recognise your precise symptoms and find a solution.

Good luck,

John

Windtalker,

I checked for water leaks and found none. Thanks.

Thanks John. I googled  as you suggested, I read a dozen articles or so and found something that might be the answer: A faulty safety pressure relief valve. For "singing tanks" most articles point to water being forced through a tight opening but could be due other reasons, as tteedd pointed out.

William02

As an electrician in the U.K., I have come across an immersion heater (water heater) and a washing machines making a high pitched noise when the heating element is on.  On both occasions it was the metal covering on the heater element That had 'pinholed' on the neutral side of the element, because it is on the neutral side the fuse doesn't blow or the circuit breaker trip.

What does happen though, is that the water is in direct contact with the heater element where the pinhole is and it causes the water to boil in that small area and hence the noise.

if you can, take the element out and check for holes or damage, if it is covered in lime scale you are as well changing it for a new one as the lime scale makes the element less efficient, if limescale is a problem, I would suggest replacing with an element made from Incalloy which are less prone to limescale damage.

hope this helps

kelju

Keiju,

The element would have had to been damaged from the very start, as the noise began  immediately after installation. The plumber and the heater service man both said the noise was normal because it was new, and that the noise would go away with time, which has not happened. It might just be a bad heater. Also the water is desalinated, and as was said fin a previous post by tteedd, limescale is not likely to form. Anyways I will keep this in mind. Thanks for your reply.