Immersion tank isn't heating water properly

Hi, hope someone can help..my hot water tank has decided to stop working...whether i use CH or immersion switch to heat my hot water tank it hardly works..the pipe at top of the pic attached is very hot but when i feel the tank its luke warm..all the other pipes around the tank are very cold...before if we had CH on at night i could have very hot water in morning..now its stone cold..my wife has a habit of stuffing clothes around the tank..could she has flicked a switch..the thermo on the tank is set to 85 degrees.
There is also a half pipe behind the door frame (cant see in pic) topped off with a large brass fitting and a little screw on top..can u tell me what this maybe...
Thanks marc

Steve

images aren't working on boards atm so can't see your pic.

Do you have a controller with separate times for CH / HW?

Could be the HW valve is not opening.

EngineerX

You could have a failure of the internal pipes of the hot water cyclinder...

meercat

check that all taps are turned off

also check that theres not a continious flow of water into washing machine

Thanks for replies..yes i have a separate controller, do you mean are my sink taps turned off? And i have a water pipe gong to my washing machine that i assume provides water for washing...

When u say internal pipes do you mean the heating element in the cylinder

Steve

Do you have one of these on the 'hot' pipe going into the cylinder?

Yes i have something similar on a pipe going into the side of the tank and its cold when heating is on..and ive a pipe going in at the top without one of those boxes and that hot when heating is on

Steve

Does the silver tab (on the left of the pic) move when you select HW on the timer?

If not, you can pull it forward and latch it to open the valve.

These are normally fairly reliable but not unheard of to stop working.

Thanks steve..my one is slightly different...it has a red circular dial..can i rotate it and play around with it..it looks like a serious piece of kit with electrical cable on it...

Steve

upload your pic to imageur and link it here so we can see what it is

Most valves like this have a manual override and / or indicator to give clue if they're working.

Will do...not sure if pics on boards is working

Just above red dial it says...flat - open

Imageur...ok let me try that

Try this link steve
http://www.seered.co.uk/sunvic_casing.JPG

Try this link steve
http://www.seered.co.uk/sunvic_casing.JPG

Steve

ok, so is the valve in that position? is there still no water flowing through it?

Tried the CH to heat the water tonight and it produced nice warm water and the pipe with the motorised value was hot...yesterday it was stone cold...not sure whats going on but it seems to work now..thanks for your help steve....

Steve

Without finding the problem, it's probably going to come back but at least you can narrow it down a bit.