immersion heater not working correctly

Old_Git

Myser wrote: »

As HappyMJ said, the immersion heater is generally only for emergency use and you should be using the gas boiler to heat the water in the tank. Besides, gas will be much cheaper to heat the whole tank!

As to why your previous immersion heater heated a full tank and this one doesn't - it could be a number of things: How many elements were there? Was the water in the tank solely heated using an immersion heater without the boiler when you heated a full tank? Power rating of the element? Length of element?

The existing immersion heater element will eventually heat a full tank of water but the time taken will depend on the type of element, whether it is covered in scale, lagging on your tank and whether hot water is being drawn while the element is heating the water.

The new element has never heated more than a third off the tank even if its on for a hour .I have no gas ,and much as I would like it there is none within 3 miles .

Myser

Are you comparing like for like? Was the previous tank and immersion heater you had exactly the same? The same amount of lagging? Are you in a hard water area? Do you know how much scale there is at the bottom of your present tank?

Did the plumber inspect the existing immersion heater element to see how much scale was on it?

Old_Git

Myser wrote: »

Are you comparing like for like? Was the previous tank and immersion heater you had exactly the same? The same amount of lagging? Are you in a hard water area? Do you know how much scale there is at the bottom of your present tank?

It is exactly the same tank .Probably hard water area .Scale in tank ,not a clue . What is a balancer ,and do I now need one

keystone

Old_Git wrote: »

My immersion heater has always over heated the water .I recently contacted an electrician as asked him to fit a thermostat.
Sparky contacted a plumber and the two off them went to work on my hot water tank .From what I gather they drained the tank (broke a pipe )fitted t thermostat and went . Now heres the problem . The immersion didnt heat the water .So sparky came back and turned up the thermostat ,the water is as hot as before he started but it only heats 1/3 off the tank .Sparky says I need a plumber to fit a balancer ?. And ideas how I fix this .I am reluctant to let sparky or his mate back

OK back to first principals with this thread.

1. Your old IM had no thermostat and was just on all the time. Yes it will heat the whole tank over time due to convection currents in the cylinder. Because it was on all the time then te water at the top of the cylinder would be too hot but as you drew it off the temp would drop and yes you could fill a bath.

2. The new thermostat fitted IM operates for a period of time but then switches off because it has reached the temperature it is set to at the stat. As a result only the top third of the cylinder is hot because without the continuously generated heat of the IM being continuously on then the convection currents don't happen to anywhere near the extent they did before. So you don't get a full bath out of it.

Thats how it was and how it is in a nutshell. I have no idea what he talking about a "balancer". There is really nothing to fix.

Does that make sense?

Cheers

Rockingit

Putting other means of heat aside, if you want to heat more of your tank then either -
1) use a longer element (so it goes deeper into the tank) or;
2) place an external (strap type) thermostat lower down (but there are some safety issues with this as you can end up with the 'top' layer of water over-heating)

Neither is particularly MSE, by the way!

Mr_Ted

Has no one considered that the Immersion heater MAY just be too short

There are different sizes of Immersion heater and the thermostats are also of differing lengths to suit the immersion, if it has an 11" immersion it will have a 7" stat and THAT will only heat the top of the cylinder

For a better quantity of hot water then a longer immersions and stat combination is required, 27 " immersion maybe

I would hazard a guess that your "trademen" have done a cheap job and put in a short immersion