Hi all,

Got a bit of a weird problem with our boiler. It's a Glow-Worm Economy
Plus EP40B (non-combi) with a pilot that should be on all the time.

If the external temperature is above about 0, it's usually OK. However,
in the recent cold snap, and after the boiler has been running for a
while (so is hot), and about 2 mins after the main burner turns off, I
can hear "clunk" and the pilot light goes out.

I had the thermocouple replaced recently, so I think that's OK. (I can
always re-light the pilot easily when the boiler is cold, and it will
stay on until the end of the next period when the main burner is used).

It seems to be something to do with the difference with the outside air
and the boiler temps.

One thing I have noticed is that only the very tip (2mm or so) of the
thermocouple is red. Could a draught caused by the temperature
difference be "pulling" the flame away from the thermocouple
sufficiently to turn it off? Is the thermocouple in slightly the wrong
position? Or could the flame not be strong enough (is there any way to
adjust it)?

Ideally I'd like to solve it myself, but understand that most things
should be done by the pros.

Cheers,

Rich

On 06/01/2015 11:07, Belperite wrote:
Hi all,

Got a bit of a weird problem with our boiler. It's a Glow-Worm Economy
Plus EP40B (non-combi) with a pilot that should be on all the time.

If the external temperature is above about 0, it's usually OK. However,
in the recent cold snap, and after the boiler has been running for a
while (so is hot), and about 2 mins after the main burner turns off, I
can hear "clunk" and the pilot light goes out.

I had the thermocouple replaced recently, so I think that's OK. (I can
always re-light the pilot easily when the boiler is cold, and it will
stay on until the end of the next period when the main burner is used).

It seems to be something to do with the difference with the outside air
and the boiler temps.

One thing I have noticed is that only the very tip (2mm or so) of the
thermocouple is red. Could a draught caused by the temperature
difference be "pulling" the flame away from the thermocouple
sufficiently to turn it off? Is the thermocouple in slightly the wrong
position? Or could the flame not be strong enough (is there any way to
adjust it)?

I would say that was it, or something like it. The thermocouple
generates enough electrical power to hold a solenoid valve open, but
only just. Lower air temperature means it won't get quite as hot, and
will produce a lower voltage. Maybe it can be moved further into the
flame?

Ideally I'd like to solve it myself, but understand that most things
should be done by the pros.

Cheers,

Rich

Cheers
--
Syd

On 06/01/2015 11:20, Syd Rumpo wrote:
On 06/01/2015 11:07, Belperite wrote:
Hi all,

Got a bit of a weird problem with our boiler. It's a Glow-Worm Economy
Plus EP40B (non-combi) with a pilot that should be on all the time.

If the external temperature is above about 0, it's usually OK. However,
in the recent cold snap, and after the boiler has been running for a
while (so is hot), and about 2 mins after the main burner turns off, I
can hear "clunk" and the pilot light goes out.

I had the thermocouple replaced recently, so I think that's OK. (I can
always re-light the pilot easily when the boiler is cold, and it will
stay on until the end of the next period when the main burner is used).

It seems to be something to do with the difference with the outside air
and the boiler temps.

One thing I have noticed is that only the very tip (2mm or so) of the
thermocouple is red. Could a draught caused by the temperature
difference be "pulling" the flame away from the thermocouple
sufficiently to turn it off? Is the thermocouple in slightly the wrong
position? Or could the flame not be strong enough (is there any way to
adjust it)?

I would say that was it, or something like it. The thermocouple
generates enough electrical power to hold a solenoid valve open, but
only just. Lower air temperature means it won't get quite as hot, and
will produce a lower voltage. Maybe it can be moved further into the
flame?

That would be my first guess too. Often they are just clamped by a plate
and a couple of self tappers, so there should be some positional
adjustment for the thermocouple.


Ideally I'd like to solve it myself, but understand that most things
should be done by the pros.

Cheers,

Rich

Cheers

Funnily enough I heard somone say that there is a part of the flame where
the thermocouple should sit as its hotter than the rest, I imagine its the
bit near the gass/air mixing bit.

All one can do I suppose is play around with it.
Brian

--
From the Sofa of Brian Gaff Reply address is active
"Syd Rumpo" wrote in message
...
On 06/01/2015 11:07, Belperite wrote:
Hi all,

Got a bit of a weird problem with our boiler. It's a Glow-Worm Economy
Plus EP40B (non-combi) with a pilot that should be on all the time.

If the external temperature is above about 0, it's usually OK. However,
in the recent cold snap, and after the boiler has been running for a
while (so is hot), and about 2 mins after the main burner turns off, I
can hear "clunk" and the pilot light goes out.

I had the thermocouple replaced recently, so I think that's OK. (I can
always re-light the pilot easily when the boiler is cold, and it will
stay on until the end of the next period when the main burner is used).

It seems to be something to do with the difference with the outside air
and the boiler temps.

One thing I have noticed is that only the very tip (2mm or so) of the
thermocouple is red. Could a draught caused by the temperature
difference be "pulling" the flame away from the thermocouple
sufficiently to turn it off? Is the thermocouple in slightly the wrong
position? Or could the flame not be strong enough (is there any way to
adjust it)?

I would say that was it, or something like it. The thermocouple generates
enough electrical power to hold a solenoid valve open, but only just.
Lower air temperature means it won't get quite as hot, and will produce a
lower voltage. Maybe it can be moved further into the flame?

Ideally I'd like to solve it myself, but understand that most things
should be done by the pros.

Cheers,

Rich

Cheers
--
Syd

In article ,
Brian Gaff wrote:
Funnily enough I heard somone say that there is a part of the flame where
the thermocouple should sit as its hotter than the rest, I imagine its
the bit near the gass/air mixing bit.

From my school physics days, when we had bunsen burners, the hottest part
was at tip of the blue part.

--
From KT24 in Surrey

Using a RISC OS computer running v5.18

/the hottest part
was at tip of the blue part/q

Istr its the inner blue cone tip on a Bunsen flame?

Jim K

In article ,
newshound writes

I would say that was it, or something like it. The thermocouple
generates enough electrical power to hold a solenoid valve open, but
only just. Lower air temperature means it won't get quite as hot, and
will produce a lower voltage. Maybe it can be moved further into the
flame?

That would be my first guess too. Often they are just clamped by a plate
and a couple of self tappers, so there should be some positional
adjustment for the thermocouple.

It would be a good idea to clean the pilot housing/cowl first, it can
get well crudded up and change the flame shape. It shouldn't be
necessary to clean the pilot jet (no poking with pins) as it is usually
protected from crud with a cowl.

--
fred
it's a ba-na-na . . . .

On Tuesday, January 6, 2015 12:02:50 PM UTC, Brian Gaff wrote:
"Syd Rumpo" wrote in message
...
On 06/01/2015 11:07, Belperite wrote:
Hi all,

Got a bit of a weird problem with our boiler. It's a Glow-Worm Economy
Plus EP40B (non-combi) with a pilot that should be on all the time.

If the external temperature is above about 0, it's usually OK. However,
in the recent cold snap, and after the boiler has been running for a
while (so is hot), and about 2 mins after the main burner turns off, I
can hear "clunk" and the pilot light goes out.

I had the thermocouple replaced recently, so I think that's OK. (I can
always re-light the pilot easily when the boiler is cold, and it will
stay on until the end of the next period when the main burner is used).

It seems to be something to do with the difference with the outside air
and the boiler temps.

One thing I have noticed is that only the very tip (2mm or so) of the
thermocouple is red. Could a draught caused by the temperature
difference be "pulling" the flame away from the thermocouple
sufficiently to turn it off? Is the thermocouple in slightly the wrong
position? Or could the flame not be strong enough (is there any way to
adjust it)?

I would say that was it, or something like it. The thermocouple generates
enough electrical power to hold a solenoid valve open, but only just.
Lower air temperature means it won't get quite as hot, and will produce a
lower voltage. Maybe it can be moved further into the flame?

Ideally I'd like to solve it myself, but understand that most things
should be done by the pros.

Cheers,

Rich

Cheers

Funnily enough I heard somone say that there is a part of the flame where
the thermocouple should sit as its hotter than the rest, I imagine its the
bit near the gass/air mixing bit.

All one can do I suppose is play around with it.
Brian

If the thermocouple is at the hottest part of the flame it isnt gonna last long.


NT

In article ,
writes:
If the thermocouple is at the hottest part of the flame it isnt gonna last long.

+1

They don't normally run red-hot, although there are some double nickel
plated ones which are designed for running hotter.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

Ideally I'd like to solve it myself, but understand that most things
should be done by the pros.

Cheers,

Rich

I've got a very old Glow Worm Space Saver 50 which has a similar problem: the flame's always close to going out which I think is caused by the cold air draft when the main burner is on and drawing fresh air in. Also the mains gas pressure might get a bit lower when it's cold due to more general public consumption so the pilot flame is smaller.
Inside the aluminium base of mine there's a pilot flame height adjuster screw. The other screw regulates the pressure to the main burner, not to be confused. If I were brave enough I might even have a fiddle.

On 06/01/2015 11:07, Belperite wrote:
Hi all,

Got a bit of a weird problem with our boiler. It's a Glow-Worm Economy
Plus EP40B (non-combi) with a pilot that should be on all the time.

If the external temperature is above about 0, it's usually OK. However,
in the recent cold snap, and after the boiler has been running for a
while (so is hot), and about 2 mins after the main burner turns off, I
can hear "clunk" and the pilot light goes out.

I had the thermocouple replaced recently, so I think that's OK. (I can
always re-light the pilot easily when the boiler is cold, and it will
stay on until the end of the next period when the main burner is used).

It seems to be something to do with the difference with the outside air
and the boiler temps.

One thing I have noticed is that only the very tip (2mm or so) of the
thermocouple is red. Could a draught caused by the temperature
difference be "pulling" the flame away from the thermocouple
sufficiently to turn it off? Is the thermocouple in slightly the wrong
position? Or could the flame not be strong enough (is there any way to
adjust it)?

Ideally I'd like to solve it myself, but understand that most things
should be done by the pros.

Cheers,

Rich

I can't really explain the temperature effect which you have seen.
Usually, it's just a case of making sure that the pilot flame is the
right size and the thermocouple is sitting within the flame.

If you can get at it, remove the pilot jet and clean it by blowing
compressed air through it. Don't prod it with a steel needle - which
could damage it. In extremis, I have been known to push a strand of soft
copper wire through a jet to clean it.

Then check to see whether the height of the pilot flame is adjustable.
Some gas valves have a separate pressure adjusting screw for the pilot.
You could tweek it up a bit - but don't touch the main burner pressure
adjustment.
--
Cheers,
Roger
____________
Please reply to Newsgroup. Whilst email address is valid, it is seldom
checked.

Thanks for all the replies guys! I've got some things to go on now. Will
probably end up getting an engineer in but have got more things to
suggest to him.

Cheers,

Rich

In article ,
Syd Rumpo wrote:

I would say that was it, or something like it. The thermocouple
generates enough electrical power to hold a solenoid valve open, but
only just. Lower air temperature means it won't get quite as hot, and
will produce a lower voltage.

And if you really wanted to test this theory, you could measure the
voltage.

Another possibility is that the solenoid is colder and this somehow
makes it require a higher voltage to operate.

-- Richard

"Richard Tobin" wrote in message ...

In article ,
Syd Rumpo wrote:

I would say that was it, or something like it. The thermocouple
generates enough electrical power to hold a solenoid valve open, but
only just. Lower air temperature means it won't get quite as hot, and
will produce a lower voltage.

And if you really wanted to test this theory, you could measure the
voltage.

Another possibility is that the solenoid is colder and this somehow
makes it require a higher voltage to operate.

-- Richard

Boiler thermocouples will typically only produce about 12 millivolts, so
really the solenoid is 'current operated' as everything is such low
resistance. You'll be hard pushed to measure the voltage difference.

Andrew

On 06/01/2015 16:46, Andrew Gabriel wrote:
In article ,
writes:
If the thermocouple is at the hottest part of the flame it isnt gonna last long.

+1

They don't normally run red-hot, although there are some double nickel
plated ones which are designed for running hotter.

I wondered about that too, but assumed they might be stainless clad,
mineral insulated chromel alumel since this is made in large quantities
for industrial use. ISTR they are rated for continuous use to around 800
C. They certainly work fairly reliably for 40 years at 650, albeit with
a drift of several degrees C because of ageing.

Belperite wrote:
Hi all,

Got a bit of a weird problem with our boiler. It's a Glow-Worm Economy
Plus EP40B (non-combi) with a pilot that should be on all the time.

If the external temperature is above about 0, it's usually OK. However,
in the recent cold snap, and after the boiler has been running for a
while (so is hot), and about 2 mins after the main burner turns off, I
can hear "clunk" and the pilot light goes out.

I had the thermocouple replaced recently, so I think that's OK. (I can
always re-light the pilot easily when the boiler is cold, and it will
stay on until the end of the next period when the main burner is used).

It seems to be something to do with the difference with the outside air
and the boiler temps.

One thing I have noticed is that only the very tip (2mm or so) of the
thermocouple is red. Could a draught caused by the temperature
difference be "pulling" the flame away from the thermocouple
sufficiently to turn it off? Is the thermocouple in slightly the wrong
position? Or could the flame not be strong enough (is there any way to
adjust it)?

Ideally I'd like to solve it myself, but understand that most things
should be done by the pros.

Cheers,

Rich

I don't know if your model has one, but ours has a metal shield (called
a 'Top Socket', for some reason). Over the years it gets crusty, and
becomes unable to point the pilot flame in the right direction. Just
needs replacing every five years or so, and the flame is as good as ever.

Best not to tamper with the flame, best to call out a gas safe approved heating engineer. After all they can solve the problem quite easily plus if they're as cheap as STL Heating then you won't be paying a fortune either. You could get some quotes in, or save the legwork, time and hassle and use STL.

On Fri, 13 Feb 2015 04:52:43 -0800 (PST), wrote:

Best not to tamper with the flame, best to call out a gas safe approved heating engineer. After all they can solve the problem quite easily plus if they're as cheap as STL Heating then you won't be paying a fortune either. You could get some quotes in, or save the legwork, time and hassle and use STL.

I'd avoid STL like the plague.

They are newsgroup spammers, and apprently need to lie and shill to get work.

On Fri, 13 Feb 2015 04:52:43 -0800 (PST),
wrote:

lying newsgroup spam for STL