Saturday, November 9, 2013

Hot Water Cylinder - Help Please

We have no hot water, from this morning but I have been out until now - after a coolish shower.. Have checked the fuse on the switch board and had a `poke round' the cylinder.but cannot see anything untoward.

Any ideas - we will probably leave it until Monday to get a plumber in rather than pay exorbitant weekend call out charges.


Anonymous said...

The usual suspect is the element. Most hot water cylinders are essentially big electric jugs and the element has a limited lifespan.

But first of all check with your electrical supplier to make sure they haven't turned off all the hot water cylinders in your area. From time to time they do this when they are doing line maintenance. Because they have to turn off part of the grid to fix the lines/transformers they reduce the load on the remaining lines by taking everyones hot water cylinders offline. Check with your neighbours to see if their hot water is off as well.

On a seperate subject - if you have an old hot water cylinder from the 80's you should really look at replacing it at some stage as they are terribly inefficient. I recommend getting one that has two heating options. These have an electrical element in them but give you the option of attaching solar, wetback or heat pump at slater date as well.

hope that is helpful.

Shane Ponting said...

Yeah get the modern cylinder with the dual element option and as anon said this means you can attach secondary heating sources like a wetback or solar.

AFAIK, the most efficient hot water option right now is a dual element cylinder with heat pump being primary in summer and wetback being primary in winter.

pdm said...

Thanks anon. We suspect the element too, I missed putting that in my post.

The cylinder is late 90's, we are the second owners but they builders are known to be dodgy and we have uncovered evidence of poor concreting etc so who knows what else is.

BTW - I normally delete anonymous posts but as I asked for help will let you off this time.

Thanks again.

KG said...

Have you tried bleeding the cylinder? There should be a valve and lever on the side of it

gravedodger said...

Hi pdm, almost certainly element unless anons theory on supply interuption is a goer.
We built ten years ago and the cylinder we opted for has two elements one on night rate and the other for a boost or in your case would act as emergency option, normally off at its wall switch.

Jimmie Walker said...

Could be the thermostat as well - mayve get both replaced in one hit.

pdm said...

Thank you everyone - problem appears to be solved.

There is a small red button on the cylinder - just after I posted I had another look around and gave the button a push - there was a small click. An hour and a half or so later we ran a tap and found we had warm water - this morning we have hot water.

I assume this is some sort of power surge or similar button although nothing else in the house seems to have been affected.

We will know next time but will also keep in mind your advice.

Striker 61 said...

Just had the same problem last week. The state of the element was bloody frightening huge holes in it.

Our regular electrician replaced it in 20 mins. $127 for labour and replacement element.

PM of NZ said...

S61, a common failure mode for elements.

The manufacturing processes stretches/draws the elements like wire drawing which seems to lead to failure via a split element after many years. The resultant earth fault path is not a hard earth which readily blows fuses/trips breakers.

This type of partial fault often lets the element work mostly OK, but ultimately leads to the element going open circuit, due to water ingress and corrosion effects.

Hence no hot water a day after the first day of failure. Will not normally be noticed with plenty of hot water in the tank, but the tank will fill with cold water as you use hot water during the first day. Second day it will be noticeably cold.