What's wrong with my hot water cylinder?

3ofeach, Jun 1, 9:31pm
About three weeks ago my hot water cylinder stopped working and a electrician was called. He installed a new element, thermostat and fuse on the power board. He set the temp to 55 degrees. Before this our hot water cylinder kept up with 5 hot showers a day and the mirror got steamed up, the hot water cupboard was warm enough to dry damp clothes in, etc. Now the shower is turned on to the hottest it will go, but is never hot and runs cold after two showers, the kettle has to be boiled to do dishes, the hot water cupboard is cold. Is the temperature just not high enough? Has the wrong element been put in so is not getting the temperature up? Is 55 degrees normally hot enough to preform? I have no idea what temperature our cylinder was on before. TIA
pettal, Jun 1, 9:37pm
maclad, Jun 1, 9:47pm
Sounds to me as if your temp is set too low,but, I am not really good with these things, in saying that, 5 showers, if long ones, especially, will drain your cylinder, especially if it is set at a low temp. Do ensure that your cylinder is not running out over the roof wasting your hot water. If so it is an easy fix in most cases.
lythande1, Jun 1, 9:49pm
Ring him back.
budgel, Jun 1, 10:09pm
It is possible that an element with a lower wattage than the previous one has been fitted, this would mean it takes longer to get back up to temperature.
You could turn the temperature up yourself by turning the dial on the thermostat up to say, 60 degrees. No point in going higher. There is a chance that the dial setting is inaccurate.
One other thing, the weather is now noticeably colder, so most of us end up running the shower at a hotter setting.
3ofeach, Jun 1, 10:15pm
Thanks for the comments. I will ring him back but I think the temperature is just set too low. The cylinder coped ok with 5 showers before, been here for 10 years and it coped when there was 8 of us. There's no water running on the roof, that's the first thing I check as have had ajax valve issues in the past with other houses. I've put the temperature on 60 to see if that makes a difference.
gabbysnana, Jun 2, 1:03am
need a bigger element rather tHan the budget one he put in,
cagivachick1, Jun 2, 2:05am
you need to get a blanket for the cylinder to stop the heat escaping into the cupboard as well
biddy6, Jun 2, 2:40am
Test the temp at the tap with a thermometer before anyone runs a shower, it should be 55* at least.
tardis537, Jun 2, 5:04am
You may have a leak somewhere. Could be small, probably under the house or in a wall or something. If hot water is leaving then cold water is entering and the size of the element will not really matter.
nzjay, Jun 2, 5:43am
You need to check the actual water temperature at a hot tap. It needs to be at least 55degC when tap is running hot.
Sometimes a thermostat is adversely affected by an element blowing and may need replacing. Also, the dial on the thermostat is only accurate to within about 5 - 10degC, you need to check the actual water temperature.
I would increase the temperature to 60degC+ to make sure the cylinder is hot enough to sterilize for Legionnaires Disease.
skin1235, Jun 2, 5:51am
nobody has asked how old the installation is, it may not have the temp reducing valves due to its age, the old thermostat was probably set at 80 and thats why 5 showers before it ran cold
could be all it needs is the thermostat winding back up to 75 or 80 again
nz, the thermo was replaced, the element, and a fuse ( simple fuse? or fuse block?, or contact breaker installed? rcd?
3ofeach, Jun 3, 5:34pm
Putting up the temperature to 60 degrees has made little/no difference. The electrician is coming back tomorrow, hope that doesn't mean another $300 bill. In answer to skin1235, the house is about 30 years old. The old fuse was replaced with a new circuit breaker. tardis537, there is no leak or else the water pump would be going all the time (we live rural). The only thing I can think of is that when the tank was emptied for the electrician then refilled, the water ran like hot chocolate, it was disgusting. Why would that happen? Rusty pipe somewhere? Could there be a blockage somewhere? Do I need a plumber instead?
mark.52, Jun 3, 5:47pm
Based on your #13, sounds like a new cylinder might be recommended. Lot of rust been accumulating over time, I'd guess.

Either the temperature is set way lower than it was (means that more of the hot will be drawn off with each shower) and/or the element is a lower wattage than the one it replaced (will simply take longer to come up to temperature.)
carter19, Jun 3, 6:16pm
The cylinder temperature must be set at 60 to kill legionnaires. The termperature at the tap will be 55 as the hot water then goes thru a tepering valve to make sure its not too hot.
skin1235, Jun 3, 8:04pm
a 30 yr old installation probably does not have a tempering valve

crank the thermo up to 75 and try again

the brown muck will be iron compounds inherent in the rural supply you use, its not uncommon, usually it sits in the bottom of the cylinder until it is emptied via the outside drain ( in some rural areas this is recommended annually )
it got disturbed when he drained the cylinder to replace the element, and he did not flush the cylinder properly before refilling, also quite common, more so now there are less and less rural plumbers who are aware of rural issues

you can check if it has a tempering valve, its usually on top of the cylinder and has a cold water supply pipe to it, there will be the normal pipe heading straight up from a tee, the valve will be after the tap on the one that comes out to the side
skin1235, Jun 3, 8:11pm
it was an electrician used to replace the element, no wonder he didn't drain the tank and flush it
the more iron compounds he leaves in there the more often he has to come back and replace the element, plus he wouldn't have a clue about rural issues either
the one good thing though, he would not have fitted a tempering valve - that is beyond his scope and needs signing off by a plumber ( at a cost)
moltenfire, Jun 6, 6:39pm
Are these valves compulsory? I got a new tank put in about 3 years ago and don't think there is anything like that, the water coming out of the tap is 70 degrees (I set the thermostat to have enough hot water for 5 people in the house). Took the plumber 3 days and heaps of new pipes plus one day of a sparky coz the old wires were rotton.
skin1235, Jun 6, 6:47pm
in the pc world of today they have become more and more compulsory, they are supposed to be fitted to every tank that a plumber does any repair to, most ignore the retrofit, but all new installations in the last 10? years have them
it started out as a safety measure to avoid scalding temps in baths and under taps, then it became a double edged drive as it is supposed to be an energy saver too now- but as you've also found its damned inconvenient most of the time, some doubts remain as to its effectiveness
lythande1, Jun 6, 7:16pm
No you don't. Modern cylinders are already insulated inside the casing.
That's why when you touch them they are not warm on the outside anymore.
kaylin, Dec 20, 9:17am
My electrician replaced the element inside the cylinder and is didn't heat after 10 hours. He rechecked and discovered he'd put in a faulty element. Maybe your element is faulty too?