I have a Glowworm Ultimate 50BF wall-mounted boiler, which is a
pumped/gravity fed system.

However, I can't find an overflow/expansion tank for it anywhere in the
house! I can't find any connection to the water supply either.

Should there always be such a tank? And should there a mechanism to top up
the circulating water when someone bleeds a radiator for example?

(I'm investigating a possible leak under a concrete floor, and half the CH
pipes are under concrete.)

--
Bartc

On Oct 6, 1:39*pm, "BartC" wrote:
I have a Glowworm Ultimate 50BF wall-mounted boiler, which is a
pumped/gravity fed system.

However, I can't find an overflow/expansion tank for it anywhere in the
house! I can't find any connection to the water supply either.

Should there always be such a tank? And should there a mechanism to top up
the circulating water when someone bleeds a radiator for example?

(I'm investigating a possible leak under a concrete floor, and half the CH
pipes are under concrete.)

--
Bartc
It has tobe there somewhere.
It may be within the boiler casing. The top up pipe is likely in
there too.

BartC wrote:
I have a Glowworm Ultimate 50BF wall-mounted boiler, which is a
pumped/gravity fed system.

However, I can't find an overflow/expansion tank for it anywhere in
the house! I can't find any connection to the water supply either.


There are no pipes leading to the boiler then?



Should there always be such a tank? And should there a mechanism to
top up the circulating water when someone bleeds a radiator for
example?
(I'm investigating a possible leak under a concrete floor, and half
the CH pipes are under concrete.)

It's usually where they protrude from concrete for some reason, I think it's
where condensation runs down and keeps the bit wet that disappears under the
floor....the part encased in concrete is usually corrosion free

"harry" wrote in message
...
On Oct 6, 1:39 pm, "BartC" wrote:

However, I can't find an overflow/expansion tank for it anywhere in the
house! I can't find any connection to the water supply either.

It has tobe there somewhere.
It may be within the boiler casing. The top up pipe is likely in
there too.

Doesn't it have to be above the level of all the radiators? (This is not
pressurised, I don't think..) The boiler is in the downstairs kitchen.

--
Bartc

"Phil L" wrote in message
news
BartC wrote:
I have a Glowworm Ultimate 50BF wall-mounted boiler, which is a
pumped/gravity fed system.

However, I can't find an overflow/expansion tank for it anywhere in
the house! I can't find any connection to the water supply either.


There are no pipes leading to the boiler then?

Five pipes in all: one is a gas pipe.

Then there are two fat pipes (28 or 22mm) to an indirectly heated hot water
cylinder.

One 15mm pipe down behind the kitchen units, via a pump hidden under there
(took me a while to find that too!), then disappears into the concrete
floor. In a corner somewhere else, one pipe leads upstairs from the
concrete.

Another 15mm pipe from the boiler goes directly upstairs. No other pipes
lead to the loft, other than
three to do with hot water (one 15mm mains pipe into the cold-water tank,
one 22mm outlet from the tank into the hot water cylinder, and the third
seems to be a 22mm venting pipe from the top of the cylinder which also
supplies the hot water taps).

Which is another strange thing: instead of a flow/return pair going to each
radiator, there seems to be just one: feeds the radiator at one end, and
then goes straight to the other end! Seems to work though...

(A lot of the damp problems are likely rising damp; but sometimes there is
an explicable flow of water from the meter in the road outside, which stops
when the stop-cock inside is turned off. But that's intermittent. No
overflows or leaking taps that I could see. The flow this morning was 2.5
litres/hour, which you think you'd notice draining somewhere! Usually it's
less or zero.)

--
Bartc

BartC wrote:


"harry" wrote in message
...
On Oct 6, 1:39 pm, "BartC" wrote:

However, I can't find an overflow/expansion tank for it anywhere in the
house! I can't find any connection to the water supply either.

It has tobe there somewhere.
It may be within the boiler casing. The top up pipe is likely in
there too.

Doesn't it have to be above the level of all the radiators? (This is not
pressurised, I don't think..) The boiler is in the downstairs kitchen.

if the CH is pressurised it wont have either a header tank or a
(permanent) connection to the mains water.

"The Natural Philosopher" wrote in message
...
BartC wrote:


"harry" wrote in message
...
On Oct 6, 1:39 pm, "BartC" wrote:

However, I can't find an overflow/expansion tank for it anywhere in the
house! I can't find any connection to the water supply either.

It has tobe there somewhere.
It may be within the boiler casing. The top up pipe is likely in
there too.

Doesn't it have to be above the level of all the radiators? (This is not
pressurised, I don't think..) The boiler is in the downstairs kitchen.

if the CH is pressurised it wont have either a header tank or a
(permanent) connection to the mains water.

It's not a modern combi boiler. And the manual for it says this:

"This boiler shall only be used on an unrestricted open vented
system with the water supply taken from a feed and expansion
cistern having a head of 27m (90ft) maximum.
This boiler must not be connected to a sealed water system"

It's just a question of finding it! But would it be unheard of for a such a
CH system to be plumbed without such a tank? It sounds highly dangerous.

--
Bartc

On Oct 6, 6:07*pm, "BartC" wrote:
"The Natural Philosopher" wrote in ...





BartC wrote:

"harry" wrote in message
....
On Oct 6, 1:39 pm, "BartC" wrote:

However, I can't find an overflow/expansion tank for it anywhere in the
house! I can't find any connection to the water supply either.

It has tobe there somewhere.
It may be within the boiler casing. * The top up pipe is likely in
there too.

Doesn't it have to be above the level of all the radiators? (This is not
pressurised, I don't think..) The boiler is in the downstairs kitchen.

if the CH is pressurised it wont have either a header tank or *a
(permanent) connection to the mains water.

It's not a modern combi boiler. And the manual for it says this:

"This boiler shall only be used on an unrestricted open vented
system with the water supply taken from a feed and expansion
cistern having a head of 27m (90ft) maximum.
This boiler must not be connected to a sealed water system"

It's just a question of finding it! But would it be unheard of for a such a
CH system to be plumbed without such a tank? It sounds highly dangerous.

--
Bartc- Hide quoted text -

- Show quoted text -

Well there are only two alternatives.
1. It has a header tank (feedwater/expansion tank)
2. It has an expansion vessel.

As the system heats up the water expands and has to go somewhere.

A header tank has to be above the highest radiator which usually means
the roof space.
An expansion tank can go anywhere but close to the boiler is usual.
Someone may have installed an expansion tank even if the instructions
say not to. Behind your kitchen units?

Your heating system may be as this:-
http://www.centralheating.org.uk/Cen...ipe_system.htm
Uncommon in domestic situations but not impossible.

Have you checked the manual number against the boiler model you have?
(may be wrong manual you have?)

Re the leak.most leaks are pretty constant. It must be underground
somewhere.
If you get a big screwdriver and press the blade end against pipes and
the other handle end against your ear you can hear/trace leaks.

BartC wrote:
I have a Glowworm Ultimate 50BF wall-mounted boiler, which is a
pumped/gravity fed system.

However, I can't find an overflow/expansion tank for it anywhere in
the house! I can't find any connection to the water supply either.

Should there always be such a tank?


Not if you have a primatic cylinder.

--
Adam

BTW. Tracing leaks by listening, you have to turn all taps etc off,
You are listening to water whistling through a small hole which could
be a leak or normal water useage. The system needs to be pressurised
but no water being used. Anything you then hear is the leak. (Don't
forget about neighbours using water too.) Move around listening to
find the noisiest place & track it down.

On 06/10/2011 19:06, harry wrote:
On Oct 6, 6:07 pm, wrote:
"The Natural wrote in ...





BartC wrote:

wrote in message
...
On Oct 6, 1:39 pm, wrote:

However, I can't find an overflow/expansion tank for it anywhere in the
house! I can't find any connection to the water supply either.

It has tobe there somewhere.
It may be within the boiler casing. The top up pipe is likely in
there too.

Doesn't it have to be above the level of all the radiators? (This is not
pressurised, I don't think..) The boiler is in the downstairs kitchen.

if the CH is pressurised it wont have either a header tank or a
(permanent) connection to the mains water.

It's not a modern combi boiler. And the manual for it says this:

"This boiler shall only be used on an unrestricted open vented
system with the water supply taken from a feed and expansion
cistern having a head of 27m (90ft) maximum.
This boiler must not be connected to a sealed water system"

It's just a question of finding it! But would it be unheard of for a such a
CH system to be plumbed without such a tank? It sounds highly dangerous.

--
Bartc- Hide quoted text -

- Show quoted text -

Well there are only two alternatives.
1. It has a header tank (feedwater/expansion tank)
2. It has an expansion vessel.

As the system heats up the water expands and has to go somewhere.

A header tank has to be above the highest radiator which usually means
the roof space.
An expansion tank can go anywhere but close to the boiler is usual.
Someone may have installed an expansion tank even if the instructions
say not to. Behind your kitchen units?

Your heating system may be as this:-
http://www.centralheating.org.uk/Cen...ipe_system.htm
Uncommon in domestic situations but not impossible.

Have you checked the manual number against the boiler model you have?
(may be wrong manual you have?)

Re the leak.most leaks are pretty constant. It must be underground
somewhere.
If you get a big screwdriver and press the blade end against pipes and
the other handle end against your ear you can hear/trace leaks.

I found one leak when I noticed the carpet was hard in one area. The
underlay had disintegrated as a result of the damp. When I excavated the
concrete floor the pipe was only leaking slightly but badly corroded.
Turned out the whole estate featured copper pipe buried in solid floor
with no protection whatsoever. Some neighbours had reinstalled complete
systems above the floor.
I did have one house with a header/expansion tank with no feed from the
supply. Had to be filled manually when required.

On 06/10/2011 13:39, BartC wrote:
I have a Glowworm Ultimate 50BF wall-mounted boiler, which is a
pumped/gravity fed system.

However, I can't find an overflow/expansion tank for it anywhere in the
house! I can't find any connection to the water supply either.

Should there always be such a tank? And should there a mechanism to top
up the circulating water when someone bleeds a radiator for example?

(I'm investigating a possible leak under a concrete floor, and half the
CH pipes are under concrete.)

I put my money on your having a Primatic cylinder - where the primary
system is automatically topped up from the domestic hot water system
without requiring a separate header tank. The work of the Devil!

See http://www.plumbingpages.com/feature...HWprimatic.cfm
--
Cheers,
Roger
____________
Please reply to Newsgroup. Whilst email address is valid, it is seldom
checked.

On 06/10/2011 16:57, harry wrote:
On Oct 6, 1:39 pm, wrote:
I have a Glowworm Ultimate 50BF wall-mounted boiler, which is a
pumped/gravity fed system.

However, I can't find an overflow/expansion tank for it anywhere in the
house! I can't find any connection to the water supply either.

Should there always be such a tank? And should there a mechanism to top up
the circulating water when someone bleeds a radiator for example?

(I'm investigating a possible leak under a concrete floor, and half the CH
pipes are under concrete.)

--
Bartc
It has tobe there somewhere.
It may be within the boiler casing. The top up pipe is likely in
there too.

Google "Primatic"!
--
Cheers,
Roger
____________
Please reply to Newsgroup. Whilst email address is valid, it is seldom
checked.

On 06/10/2011 17:33, The Natural Philosopher wrote:


if the CH is pressurised it wont have either a header tank or a
(permanent) connection to the mains water.

Nor will have a gravity primary HW circuit!
--
Cheers,
Roger
____________
Please reply to Newsgroup. Whilst email address is valid, it is seldom
checked.

On Oct 6, 6:07*pm, "BartC" wrote:
"The Natural Philosopher" wrote in ...





BartC wrote:

"harry" wrote in message
....
On Oct 6, 1:39 pm, "BartC" wrote:

However, I can't find an overflow/expansion tank for it anywhere in the
house! I can't find any connection to the water supply either.

It has tobe there somewhere.
It may be within the boiler casing. * The top up pipe is likely in
there too.

Doesn't it have to be above the level of all the radiators? (This is not
pressurised, I don't think..) The boiler is in the downstairs kitchen.

if the CH is pressurised it wont have either a header tank or *a
(permanent) connection to the mains water.

It's not a modern combi boiler. And the manual for it says this:

"This boiler shall only be used on an unrestricted open vented
system with the water supply taken from a feed and expansion
cistern having a head of 27m (90ft) maximum.
This boiler must not be connected to a sealed water system"

It's just a question of finding it! But would it be unheard of for a such a
CH system to be plumbed without such a tank? It sounds highly dangerous.

--
Bartc- Hide quoted text -

- Show quoted text -

http://www.plumbingpages.com/feature...HWprimatic.cfm

On 06/10/2011 19:06, harry wrote:


Well there are only two alternatives.

All together now, "Oh no there are not!"

1. It has a header tank (feedwater/expansion tank)
2. It has an expansion vessel.

3. PRIMATIC
--
Cheers,
Roger
____________
Please reply to Newsgroup. Whilst email address is valid, it is seldom
checked.

In message , Roger Mills
writes
On 06/10/2011 19:06, harry wrote:


Well there are only two alternatives.

All together now, "Oh no there are not!"

1. It has a header tank (feedwater/expansion tank)
2. It has an expansion vessel.

3. PRIMATIC

We've already established that Harry doesn't understand much about
boilers

--
geoff

"BartC" wrote in message ...

However, I can't find an overflow/expansion tank for it anywhere in the
house! I can't find any connection to the water supply either.

(I'm investigating a possible leak under a concrete floor, and half the CH
pipes are under concrete.)

Thanks for the replies. This primatic cylinder sounds like the most likely
(only!) option!

That makes it a little more difficult to isolate the CH circuit, but it
sounds now it can't be the main cause of the leak, as that could only have
been the water header tank filling up, and I would have heard it. More tests
needed I think.

The downstairs CH pipes in concrete are copper with no protection, so that
still needs to be considered. (A couple of places, the concrete over a pipe
has crumbled away, and the pipe feels clammy.) Although ultimately the
downstairs can be replumbed (if I can figure out how to drain and refill
such a system).

The most critical damp point is at the bottom of a door frame, away from
likely CH pipe runs. The timber extends below floor level a few inches, and
is actually wet, not just damp! (And is now rotten.)

Can rising damp cause this? There is no measurable leak (on the meter)
between the outside and the stopcock when the latter is turned off, and this
run is probably under concrete as well, so hopefully it is not the incoming
water pipe.

--
Bartc

Another possibility is that you have a combination cylinder, this is
essentially a "normal"cylinder combined with a header tank on top of it.

It is hard to tell the difference between a normal cylinder and a
combination cylinder on account of the expanded insulating foam put onto it,
but a combination cylinder will have a plastic lid on the top which you can
lift off. You will then see the header tank and a ball float valve.

Regards

Stephen

"BartC" wrote in message ...


"BartC" wrote in message
...

However, I can't find an overflow/expansion tank for it anywhere in the
house! I can't find any connection to the water supply either.

(I'm investigating a possible leak under a concrete floor, and half the
CH pipes are under concrete.)

Thanks for the replies. This primatic cylinder sounds like the most likely
(only!) option!

That makes it a little more difficult to isolate the CH circuit, but it
sounds now it can't be the main cause of the leak, as that could only have
been the water header tank filling up, and I would have heard it. More
tests needed I think.

The downstairs CH pipes in concrete are copper with no protection, so that
still needs to be considered. (A couple of places, the concrete over a
pipe has crumbled away, and the pipe feels clammy.) Although ultimately
the downstairs can be replumbed (if I can figure out how to drain and
refill such a system).

The most critical damp point is at the bottom of a door frame, away from
likely CH pipe runs. The timber extends below floor level a few inches,
and is actually wet, not just damp! (And is now rotten.)

Can rising damp cause this? There is no measurable leak (on the meter)
between the outside and the stopcock when the latter is turned off, and
this run is probably under concrete as well, so hopefully it is not the
incoming water pipe.

--
Bartc

On Oct 6, 8:11*pm, geoff wrote:
In message , Roger Mills
writes

On 06/10/2011 19:06, harry wrote:

Well there are only two alternatives.

All together now, "Oh no there are not!"

1. It has a header tank (feedwater/expansion tank)
2. It has an expansion vessel.

*3. PRIMATIC

We've already established that Harry doesn't understand much about
boilers

--
geoff

Yes it must be a primatic. I forgotten all about them, haven't seen
one for years.