Base of hot cylinder cold - no central heating

[ozhall]

Hi All,
I've recently purchased a flat built in the 1930's and am having some trouble with the central heating.
Firstly it's an indirect boiler (two cisterns on the loft with expansion pipes) but only run by an electrical immersion heater.
I've replaced the old 27" immersion heater (it's length covers 3/4's of the cylinder height) as it was faulty but when it heats the cylinder the base of the cylinder stays cold and the top of the cold section of the cylinder is in-line with the inlet pipe of the central heating.

No matter what I try the central heating will not heat up.
I've turned the C/H off for half a day and the top inlet pipe started to get hot from convection but the base of cylinder still cold. I then turned the C/H on and the circulation pump kicked in, the pipe suddenly went cold (so the C/H is flowing) but still no heat as the base of the cylinder is still cold.

The upper two thirds of the cylinder is nice and hot (60deg and can shower fine) but the base is always cold where the C/H inlet and outlet pipes are connected.

does anyone have any ideas on what is going on.

I've looked around the cylinder to see if there is another immersion heated but can't find one and no extra electrical cabling running down below.

Thanks

 

[markfxy]

:speechless:wtf

 

[Gray0689]

Let me get this straight you have an indirect cylinder and your using the immersion to try and heat the hole thing so the coil can take the heat from it so you can pump it around the radiators is that what I'm reading or just being stupid

 

[PlumbBobBob]

Let me get this straight you have an indirect cylinder and your using the immersion to try and heat the hole thing so the coil can take the heat from it so you can pump it around the radiators is that what I'm reading or just being stupid

that's how i read it too Gray

 

[AlexGas]

...does anyone have any ideas on what is going on?

You are out of your depth.

 

[Gray0689]

Thought I was going mental there lol cheers mate

 

[Gray0689]

Please take a few pictures of cylinder
You may not have what you think you have

 

[rpm]

Please take a few pictures of cylinder
You may not have what you think you have

Finally somebody is trying to help the guy instead of taking the P*ss.

Am I the only one getting fed up with these sort of replies to newbies, what happened to the be nice rule?

 

[Gray0689]

Think most want to help but there seems to be a growing number of posts that have there mind made up before they post then refuse to accept the advice given

 

[SimonG]

Finally somebody is trying to help the guy instead of taking the P*ss.

Am I the only one getting fed up with these sort of replies to newbies, what happened to the be nice rule?

Dont think they need help. I think its doing what it should.

Op said that doesnt use coil for hot water, only immersion. It wont heat any water below the immersion element.

 

[rpm]

Think most want to help but there seems to be a growing number of posts that have there mind made up before they post then refuse to accept the advice given

Totally agree with your point but as the guy hasn`t even replied thats not valid yet.

 

[rpm]

Dont think they need help. I think its doing what it should.

Op said that doesnt use coil for hot water, only immersion. It wont heat any water below the immersion element.

Even I realised that when I read it mate but did he really deserve the first couple of replies?

 

[Gray0689]

Totally agree with your point but as the guy hasn`t even replied thats not valid yet.

I meant in other posts mate

 

[rpm]

I meant in other posts mate

On that subject I`m going to start another thread in the Arms.
Give me a couple of seconds.

 

[tamz]

Possibly a back boiler with the pilot out. Most people think a cylinder is the boiler.
To the OP.
Either ask a neighbour or pay some local plumber to come in and have a run through your system with you. It won't cost much.

 

[jtsplumbing]

Think you need to call someone in to check out your system, it looks kike you boiler is not working , do you know where it is located ? if its on the wall be a white metal box with some switches on the front, connected to gas supply, now it could be in a cupboard somewhere ask some of your nabours they could have same system, But if you don't understand it you would be best to call out local boiler engineer, put a request on here one of the experienced people on here may be close by and be able to help, Good Luck

 

[ozhall]

Hi All,
I've taken some photo's but can't add them to this post.
I'll explain again.
I have the main water tank in the loft which has a cold feed running straight down to the base of the hot water cylinder in the cupboard.
Out of the top of the cylinder is the hot feed to all taps and the first 'T' off is also the expansion pipe going back upto the water tank.
There are another two pipes (central heating) one above each other in the lower section of the hot water cylinder which head down under floor boards with one going through a circulation pump first (this pipe also has another pipe connection at the circulation pump and going under the floor boards)

I have looked everywhere for a gas boiler but can't find one. We have gas in the flat connected to the cooker and gas fire place but no boiler to be found. Also the last gas safety inspection report shows no boiler just checks for the cooker and fire place so I assume that the system to totally run by an immersion element.

And when I turn on the HWS the element heats the cylinder but not down to where the C/H pipes connect (almost like there is a baffle in the cylinder.

I have an engineer coming but not till tuesday so thought you guys could give me some tips.

 

[Dotty]

You've quite possibly got a back boiler tucked in behind the fire. Pound to a pinch it's not been serviced correctly if it's not mentioned on the safety cert.

Your cylinder is doing its job. It's not designed to heat the flat.

 

[jtsplumbing]

Have you got a time control somewhere ? switch turned off that's powers system ! look under gas fire, can you see another set of controls ? Again ask others in other flats more than likely got same system

 

[stevetheplumber]

if you look at the bottom of the fire you may find a removable panel that will have instructions on the back explaining how to light the pilot on your boiler the immersion heater is usually used as a back up if the boiler fails
have you looked for a timeclock and roomstat in the flat chance are the timeclock will be either on the side of the chimney breast or in the airing cupboars the room stat will be on the wall in usually in the lounge or hall both of these need to be on the clock may need to be set to water and heating
you do need to check the boiler to see if the pilot is alight look under the fire for a small window about 2 inches squareroughly a foo=ot back from the fire
i would recomend if its not been used for a while you get it serviced asap and fit a CO alarm

 

[DrainMedic]

When you say you have an 'indirect boiler' do you mean an indirect cylinder? The cylinder being the bit you've fitted the immersion to.

This is itself will not heat the central heating system, it's there solely to heat the water which you'll then use to shower etc.

the connections on the side of the cylinder are for the cold inlet from the tank (to keep the cylinder full and provide the pressure to force the water out of your taps - this is the pipe at the bottom of the cylinder with a drain cock on it) and (usually) on the opposite side the two connections are for hot water from your central heating boiler (gas/electric/oil etc) which will be used to heat the water inside the cylinder.

you may also have a third connection (with a pump on it) about 3/4 of the way up the cylinder which is used when the outlets, taps, showers etc are far away from the cylinder. In this case, hot water is pumped out of the cylinder at the top, pumped somewhere close to the taps around the property then returned back to the cylinder into this port high on the side. Sometimes this return pipe goes into the cold inlet right at the bottom, but the tell tale is the pump attached will usually be constantly running.

have a look and see what you can find out, and like someone else said, try and post some pictures and we'll try our best for you.

Sorry for for the laymans terms!

At at least you're prepared to get up and have a go eh!

Best set of luck!