UK diy (uk.d-i-y) For the discussion of all topics related to diy (do-it-yourself) in the UK. All levels of experience and proficency are welcome to join in to ask questions or offer solutions.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Peter Smithson
 
Posts: n/a
Default central heating not working

I've just moved into a house about 3 weeks ago and the central heating
does not work. I've not owned a house before so I'm a real novice.

It has a gas boiler that heats the hot water and is supposed to heat the
radiators too. I've had a look on the web and I think my hot water is
working as it has some very large pipes which are probably working by
convection/gravity to do the hot water. I think it's probably the
original boiler and therefore made around 1984. It's a glowworm (I
think that's right).

Seems to me there are a few possible causes

1) Water pump isn't working. Yet it has a voltage going into it and
I'd expect to feel some heat in the radiator pipes coming out of the
boiler just by convection but they are stone cold. On the other hand,
it doesn't make any sound at all - I'd have thought you'd hear
something.

2) There's no water in the sytem at all - not likley I would have
thought. I'm going to try bleeding a radiator tonight to confirm.

3) Some problem in the boiler. Is there a way it could be providing hot
water but no heat at all to the CH circuit?

An engineer is coming round on Wednesday to check the boiler anyway but
it'd be nice to have some heating before then!

Cheers

Peter
--
http://www.beluga.freeserve.co.uk
  #2   Report Post  
BillR
 
Posts: n/a
Default central heating not working

Peter Smithson wrote:
I've just moved into a house about 3 weeks ago and the central heating
does not work. I've not owned a house before so I'm a real novice.

It has a gas boiler that heats the hot water and is supposed to heat
the radiators too. I've had a look on the web and I think my hot
water is working as it has some very large pipes which are probably
working by convection/gravity to do the hot water. I think it's
probably the original boiler and therefore made around 1984. It's a
glowworm (I think that's right).

Seems to me there are a few possible causes

1) Water pump isn't working. Yet it has a voltage going into it and
I'd expect to feel some heat in the radiator pipes coming out of the
boiler just by convection but they are stone cold. On the other hand,
it doesn't make any sound at all - I'd have thought you'd hear
something.

If the voltage going into the pump is 240v ac then it should be running.
If not it ought to be getting quite warm....
Often they seize up when not used in the summer and can be freed up by
removing the large round screw cover (with a coin) and rotating the end of
the shaft with a screwdriver. Do this with ch power off.
There may be some water leakage when you remove the cover, its nothing to
worry about but don't let it fall on anything that matters as it will stain.
If the pump has burnt out, possible if it has been powered on whilst jammed,
they they are fairly easy to replace as they have isolating valves either
side. Get new one of equal or higher head rating (4/5m) from B&Q or similar.
Obviously you need big spanner/wrench for pump connections.

2) There's no water in the sytem at all - not likley I would have
thought. I'm going to try bleeding a radiator tonight to confirm.

3) Some problem in the boiler. Is there a way it could be providing
hot water but no heat at all to the CH circuit?

An engineer is coming round on Wednesday to check the boiler anyway
but it'd be nice to have some heating before then!

Cheers

Peter




  #3   Report Post  
Christian McArdle
 
Posts: n/a
Default central heating not working

I've just moved into a house about 3 weeks ago and the central heating
does not work. I've not owned a house before so I'm a real novice.


Probably the pump. Could be the zone valve, although they might not have
bothered to fit one. Even if they have, the controls should have been wired
so that the pump only fires when the valve is detected to be open, but they
might not have bothered to wire properly.

Christian.


  #4   Report Post  
Roger Mills
 
Posts: n/a
Default central heating not working


"Peter Smithson" wrote in message
...
I've just moved into a house about 3 weeks ago and the central heating
does not work. I've not owned a house before so I'm a real novice.

It has a gas boiler that heats the hot water and is supposed to heat the
radiators too. I've had a look on the web and I think my hot water is
working as it has some very large pipes which are probably working by
convection/gravity to do the hot water. I think it's probably the
original boiler and therefore made around 1984. It's a glowworm (I
think that's right).

Seems to me there are a few possible causes

1) Water pump isn't working. Yet it has a voltage going into it and
I'd expect to feel some heat in the radiator pipes coming out of the
boiler just by convection but they are stone cold. On the other hand,
it doesn't make any sound at all - I'd have thought you'd hear
something.

2) There's no water in the sytem at all - not likley I would have
thought. I'm going to try bleeding a radiator tonight to confirm.

3) Some problem in the boiler. Is there a way it could be providing hot
water but no heat at all to the CH circuit?

An engineer is coming round on Wednesday to check the boiler anyway but
it'd be nice to have some heating before then!

Cheers

Peter
--
http://www.beluga.freeserve.co.uk


As others have said, it's most likely a duff pump.

But also check:
* the programmer - should be set to Heating On
* the room stat - should be set to a high enough temperature
* radiator valves - some fool may have turned them all off for the summer!

It's unlikely that there's no water in the system - otherwise the hot water
wouldn't work. But check the small header/expansion tank anyway, and check
that it's ball-valve works properly. [It should only have a couple of inches
of water in the bottom when the system is cold - but the outlet in the
bottom of the tank *must* be covered - otherwise air will be drawn into the
system].

HTH,
Roger


  #5   Report Post  
Peter Smithson
 
Posts: n/a
Default central heating not working

In article ,
says...

As others have said, it's most likely a duff pump.


OK - I'll see if it's getting hot or not and that will tell me if it's
burnt out or jammed ( I think ).

But also check:
* the programmer - should be set to Heating On
* the room stat - should be set to a high enough temperature
* radiator valves - some fool may have turned them all off for the summer!


There's no room stat and there's no heat in the pipes leaving the boiler
for the CH so I doubt the radiator valves so I think I'm OK there.
Programer is OK - I checked it gets voltage at the pump and I presume
that voltage is only there when the CH is on - I could check that to
make sure it does turn it off just out of curiosity.

It's unlikely that there's no water in the system - otherwise the hot water
wouldn't work. But check the small header/expansion tank anyway, and check
that it's ball-valve works properly. [It should only have a couple of inches
of water in the bottom when the system is cold - but the outlet in the
bottom of the tank *must* be covered - otherwise air will be drawn into the
system].


I've had a look at
http://www.technosolution.co.uk/diy/...ms/systems.htm
and I see what you mean - the water for heating the hot water and
radiators seems to be linked. Yet looking at my boiler with the cover
off shows two thick pipes going in on one side and two thick pipes going
in on the other. One pair of pipes gets hot and heads off to the hot
water system. The other pair don't get hot and are linked to the CH
system. So I thought they were seperate. Is that possible?

There's a picture of the outside here, I think this link will work -

http://uk.f2.pg.photos.yahoo.com/ph/...boiler&.view=t


the 2 pipes on the left get hot. None of the ones on the right do.

Thanks for everyones replies.

Peter
--
http://www.beluga.freeserve.co.uk


  #6   Report Post  
Christian McArdle
 
Posts: n/a
Default central heating not working

radiators seems to be linked. Yet looking at my boiler with the cover
off shows two thick pipes going in on one side and two thick pipes going
in on the other. One pair of pipes gets hot and heads off to the hot


Yep. You appear to have gravity circulation. I would recommend upgrading
this. The simplest method would be to add a 2 port valve, pump and cylinder
thermostat. This will stop the water getting too hot, save energy and reduce
boiler cycling. In the longer term, the systems can be combined when you
replace the boiler with a single circuit controlled by the 2 zone valves.
You then only need one pump.

You also say there is no room stat. Add one ASAP (and a zone valve if it has
none) and make sure other rooms have TRVs too. You are wasting gas like it
grows on trees.

Christian.


  #7   Report Post  
mike ring
 
Posts: n/a
Default central heating not working

Peter Smithson wrote in
:

One pair of pipes gets hot and heads off to the hot
water system. The other pair don't get hot and are linked to the CH
system. So I thought they were seperate. Is that possible?


I am no expert, but in my recent studies I came across this

http://www.gasman.fsbusiness.co.uk/g...ed_heating.htm

which looks like what you are describing.

If it is, then you need, like everybody has said, to look at the pump.

HTH

mike r
  #8   Report Post  
Roger Mills
 
Posts: n/a
Default central heating not working


"Peter Smithson" wrote in message
...
In article ,
says...


and I see what you mean - the water for heating the hot water and
radiators seems to be linked. Yet looking at my boiler with the cover
off shows two thick pipes going in on one side and two thick pipes going
in on the other. One pair of pipes gets hot and heads off to the hot
water system. The other pair don't get hot and are linked to the CH
system. So I thought they were seperate. Is that possible?

There's a picture of the outside here, I think this link will work -

http://uk.f2.pg.photos.yahoo.com/ph/...boiler&.view=t


the 2 pipes on the left get hot. None of the ones on the right do.

Thanks for everyones replies.

Peter
--
http://www.beluga.freeserve.co.uk


What you've got is a gravity hot water and pumped central heating system.
They share the *same* water - which gets heated by the boiler, and either
flows by gravity through the indirect coil in the hot water cylinder - or
by pump action through the radiators.

Pipes only get got (except for a small amount of conduction) when hot water
flows through them. If there is no flow round the radiator circuit, the
pipes in that circuit (the pair on the heating side of the boiler) won't get
hot. You have to determine *why* there is no flow. As I said earlier, it is
probably a duff pump - but it just *could* be that all the radiators are
turned off - because this would effectively kill that circuit.

Roger


  #10   Report Post  
David W.E. Roberts
 
Posts: n/a
Default central heating not working


"Christian McArdle" wrote in message
et...
snip
You also say there is no room stat. Add one ASAP (and a zone valve if it

has
none) and make sure other rooms have TRVs too. You are wasting gas like it
grows on trees.


Slightly puzzled - I thought the OP said that all radiators had TRVs.
If so, why do you need a room thermostat?
In fact, which room do you put it in?

If I understand correctly, a room thermostat turn the CH off once a specific
room has reached a certain temperature.
At this point any other room which is below optimum temperature cannot heat
up.

This leads me to deduce that the room thermostat should be in the room to
heat up last and cool down first, so that all the other rooms are able to
come up to temperature and then shut down the radiators via TRVs to keep at
optimum temperature.

If this is correct then the remote wiring required to install a thermostat
just to regulate one room seems pointless - just give this room a TRV as
well.

Or am I missing something?

Cheers
Dave R





  #11   Report Post  
Dave Liquorice
 
Posts: n/a
Default central heating not working

On Sat, 27 Sep 2003 11:22:40 +0100, David W.E. Roberts wrote:

Slightly puzzled - I thought the OP said that all radiators had
TRVs. If so, why do you need a room thermostat?


To stop the boiler cycling through the bypass loop once the all the
TRVs have shutdown because the house is warm. This cycling is using
energy just to keep the boiler warm not the house. OK it will heat the
house but it is heat which isn't required.

In fact, which room do you put it in?


One without a TRV on the radiator. The hall is generally accepted to
be a good place but there are almost religious debates about this from
time to time. Otherwise your understanding of the implications of the
room stat on system with TRVs is correct

--
Cheers
Dave. pam is missing e-mail



  #12   Report Post  
Roger Mills
 
Posts: n/a
Default central heating not working


"David W.E. Roberts" wrote in message
...


If this is correct then the remote wiring required to install a thermostat
just to regulate one room seems pointless - just give this room a TRV as
well.

Or am I missing something?

Cheers
Dave R



Yes! The boiler and pump will continue to run unnecessarily unless switched
off by a stat.

Unless, of course, you go for a Rolls Royce solution - and put a zone valve
controlled by a room stat on each radiator feed - and connect all the zone
valves' voltage-free contacts in parallel to control the boiler and pump.
That way, you can conrol the temperature of each room independendly (like
with a TRV) BUT also have the system automatically shut down when all
demands are satisfied. [If you used a programmable stat in each room, you
could even have different rooms heated at different times if this would be
useful for your particular lifestyle].

Roger


Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Pool water in central heating system Andy Hall UK diy 1 September 2nd 03 06:01 PM
central heating pipework Robert Frame UK diy 2 August 16th 03 01:57 PM
Making a ruin into something habitable. Liz UK diy 140 August 12th 03 01:03 PM
Further to my last post entitled 'Flushing and treating central heating question' David W.E. Roberts UK diy 0 July 29th 03 08:15 PM
Costs for Gas Central heating from Electric storage Richard Markham UK diy 0 July 14th 03 09:46 PM


All times are GMT +1. The time now is 09:33 AM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 DIYbanter.
The comments are property of their posters.
 

About Us

"It's about DIY & home improvement"