Firstly I know very little (if nothing about Boilers) but wish to learn and eventually be able to maintain my own boiler myself and this seems a good place to learn how to start.

I have a 'Direct Combination Cylinder' boiler and my white meter heating has recently stopped working (the lower cylinder). I believe this may be the thermostat and I wish to change this myself but haven’t the slightest clue how to proceed. Before I buy a thermostat Im going to switch my top and bottom ones to see if this fixes the problem (although I will have to wait overnight to find out). Ive also been told to push the reset button before doing anything on my boiler to see if this fixes it, but I cant find the button. I am confident enough to change the thermostat myself, but I would rather ask advice before attempting it.

Please can someone let me know what I should do and in what order? (obviously switch the power off at the mains first) but after that???... (yes I know that little about boilers) and also where the reset switch would lilkley be?

I have attached some photos.

Thanks very much for any advice in advance

In an earlier contribution to this discussion,
SCOTT495 wrote:

Firstly I know very little (if nothing about Boilers) but wish to
learn and eventually be able to maintain my own boiler myself and
this seems a good place to learn how to start.

I have a 'Direct Combination Cylinder' boiler and my white meter
heating has recently stopped working (the lower cylinder). I believe
this may be the thermostat and I wish to change this myself but
haven't the slightest clue how to proceed. Before I buy a thermostat
Im going to switch my top and bottom ones to see if this fixes the
problem (although I will have to wait overnight to find out). Ive
also been told to push the reset button before doing anything on my
boiler to see if this fixes it, but I cant find the button. I am
confident enough to change the thermostat myself, but I would rather
ask advice before attempting it.

Please can someone let me know what I should do and in what order?
(obviously switch the power off at the mains first) but after
that???... (yes I know that little about boilers) and also where the
reset switch would lilkley be?

I have attached some photos.

Thanks very much for any advice in advance


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Download: https://www.diybanter.com/attachments/uk-diy/80-replacing-boiler-thermostat-2-jpg |
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Firstly, you need to sort out the terminology!

What you've got ISN'T a boiler - it's a hot water cylinder heated by two
immersion heaters.

If one of these has stopped working, it *could* be the thermostat but it's
just as likely - maybe *more* likely - to be the electrical heating element
in the immersion heater.

I can't quite make out all the wiring in your picture, but the red thing is
the thermostat. The live side of the supply cable will go to one side of the
stat, and the other side of the stat will be connected to one side of the
element. The neutral side of the supply will be connected to the other side
of the element.

You need to switch everything off, and disconnect enough to be able to get
at the cables going to the element - and then check with a suitable meter
that you have continuity across the element.

If this sounds totally foreign to you, it's probably safer not to touch it
but to call in a qualified electrician instead.

Incidentally, your stat is currently set at 80 deg - which would be
dangerously (scaldingly) hot if it actually managed to achieve that!
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

On Mon, 11 Apr 2005 14:23:59 +0100, Set Square wrote:

In an earlier contribution to this discussion,
SCOTT495 wrote:

Firstly I know very little (if nothing about Boilers) but wish to
learn and eventually be able to maintain my own boiler myself and
this seems a good place to learn how to start.

I have a 'Direct Combination Cylinder' boiler and my white meter
heating has recently stopped working (the lower cylinder). I believe
this may be the thermostat and I wish to change this myself but
haven't the slightest clue how to proceed. Before I buy a thermostat
Im going to switch my top and bottom ones to see if this fixes the
problem (although I will have to wait overnight to find out). Ive
also been told to push the reset button before doing anything on my
boiler to see if this fixes it, but I cant find the button. I am
confident enough to change the thermostat myself, but I would rather
ask advice before attempting it.

Please can someone let me know what I should do and in what order?
(obviously switch the power off at the mains first) but after
that???... (yes I know that little about boilers) and also where the
reset switch would lilkley be?

I have attached some photos.

Thanks very much for any advice in advance


+-------------------------------------------------------------------+
Filename: 2.jpg |
Download: http://www.diybanter.com/attachment.php?attachmentid=80 |
+-------------------------------------------------------------------+

Firstly, you need to sort out the terminology!

What you've got ISN'T a boiler - it's a hot water cylinder heated by two
immersion heaters.

If one of these has stopped working, it *could* be the thermostat but it's
just as likely - maybe *more* likely - to be the electrical heating element
in the immersion heater.

I can't quite make out all the wiring in your picture, but the red thing is
the thermostat. The live side of the supply cable will go to one side of the
stat, and the other side of the stat will be connected to one side of the
element. The neutral side of the supply will be connected to the other side
of the element.

You need to switch everything off, and disconnect enough to be able to get
at the cables going to the element - and then check with a suitable meter
that you have continuity across the element.

If this sounds totally foreign to you, it's probably safer not to touch it
but to call in a qualified electrician instead.

Incidentally, your stat is currently set at 80 deg - which would be
dangerously (scaldingly) hot if it actually managed to achieve that!

One or two more points.

If thermostat needs replacing then you are likely to need a short (7")
one. Anyway the old unit will be a guide.

Replacement units will now have a cutout button on the thermostat which
can only be reset by pushing it.

80C is very hot - but since this is off peak heating it is important to
get the water a hot as possible. IIRC there is a relaxation of the 65C
max rule for off-peak storage water heating. However great care must be
used when using this water.

If the element needs replacing then you are info some serious work if you
have not done one before.

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html