tvmo wrote:

I'm moving into a new home that has an old boiler, the label on it
says "Thorn EMI Heating Limited M56/76 & M80/100 gas boilers". There
is a cylinder above it in the bedroom and in the attic there is a cold-
water cistern and a feed-and-expansion cistern. I'm after some general
advice (be gentle on my I am totally ignorant re central heating/water
systems!):

This will give you the background info:

http://wiki.diyfaq.org.uk/index.php?...entral_Heating
http://wiki.diyfaq.org.uk/index.php?..._Water_Systems

In general terms:

1. The timer on the system is not working - could I fit a modern
thermostat and timer to the boiler?

More than likely.

2. Alternatively, if the boiler is replaced would I need to replace
all the radiators as well? Is there a difference between modern
pipework and older (possibly over 20 years old) pipework diameter?

Unless you have a particularly unusual design then chances are what you
have will be fine if not too badly corroded. Modern systems are usually
designed to run slightly cooler than older ones, so you may need to swap
some rads about if you find some rooms are on the cool side and
balancing alone does not fix it.

3. Can the cylinder be moved into the attic? What affect would this
have on the water cisterns already in the attic?

It can, but the cold water cistern would need to be raised up above it
on a suitable platform.

4. If I replace the boiler, what should I replace it with? I think a
combi would be out of the question as the house is a large 5-
bedroomed, with a couple of bathrooms.

This is a deep question. Have a read of the links above to get familiar
with the options.

--
Cheers,

John.

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