Got an issue with my gas back boiler thingy. It's a Potterton Fireside
"black Beauty" FWIW - in the house when I moved in, about 12-14 years
old.

It had the same problem about 2.5 years ago - basically the pilot light
goes out - re-lights easyily enough - runs for a while - hours to weeks,
then goes out again. Eventually gets worse and worse. Got a man in and
he changed the thermocouple, but even then it still goes out every now
and then - until today when it seems back to hourly...

Any clues of what I can do myself before calling a man in? It looks
relatively straightforward from what I can see - I can identify the pilot
feed to the manifold, as well as the thermocouple - I'd not hesitate to
replace either if they were at fault - but I've no real experience of
this sort of fault - what's it likely to be - the pilot itself or the
thermocouple - or maybe something else?

The room itself is well ventilated, so I don't think it's lack of oxygen
or CO buildup. Pilot light burns with a blue flame (although I think
it's a bit "fuzzy", but I don't know if it's meant to be like that!)

Loathe to even think about a new boiler as it's otherwise sound and
has a functional (if rather ugly) gas fire attached, and is in a place
where running a condensate drain would be virtually impossible (middle
of house in an old fireplace!)

Any clues welcome!

Cheers,

Gordon

"Gordon Henderson" wrote in message
...
Got an issue with my gas back boiler thingy. It's a Potterton Fireside
"black Beauty" FWIW - in the house when I moved in, about 12-14 years
old.

It had the same problem about 2.5 years ago - basically the pilot light
goes out - re-lights easyily enough - runs for a while - hours to weeks,
then goes out again. Eventually gets worse and worse. Got a man in and
he changed the thermocouple, but even then it still goes out every now
and then - until today when it seems back to hourly...

Any clues of what I can do myself before calling a man in? It looks
relatively straightforward from what I can see - I can identify the pilot
feed to the manifold, as well as the thermocouple - I'd not hesitate to
replace either if they were at fault - but I've no real experience of
this sort of fault - what's it likely to be - the pilot itself or the
thermocouple - or maybe something else?

With our very old gas boiler there were only two things that went wrong:
(1) Thermocouple would fail every few years.
(2) Pilot light jet would get blocked with crud every few years. The
symptoms were similar to yours. Dust/dirt blocked the jet so it went out.
Gas turned off. Dirt dropped back and cleared the jet. Lit the jet. Repeat
as required. A good clean out of the pilot feed and jet cured this.

Gordon Henderson explained :
Any clues of what I can do myself before calling a man in? It looks
relatively straightforward from what I can see - I can identify the pilot
feed to the manifold, as well as the thermocouple - I'd not hesitate to
replace either if they were at fault - but I've no real experience of
this sort of fault - what's it likely to be - the pilot itself or the
thermocouple - or maybe something else?

Check the condition of the 'nose' of the thermocouple, see if it looks
burnt. Check it is properly in the flame, check the draft shield is
properly placed to stop the wind or drafts blowing it out and that the
brass nut is not loose where it enters the gas valve.

If the flame looks poor, the jet could be sooted up.

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

In article ,
Harry Bloomfield wrote:
Gordon Henderson explained :
Any clues of what I can do myself before calling a man in? It looks
relatively straightforward from what I can see - I can identify the pilot
feed to the manifold, as well as the thermocouple - I'd not hesitate to
replace either if they were at fault - but I've no real experience of
this sort of fault - what's it likely to be - the pilot itself or the
thermocouple - or maybe something else?

Check the condition of the 'nose' of the thermocouple, see if it looks
burnt. Check it is properly in the flame, check the draft shield is
properly placed to stop the wind or drafts blowing it out and that the
brass nut is not loose where it enters the gas valve.

If the flame looks poor, the jet could be sooted up.

Sounds like a bit of TLC might be all that's needed then. I'll have a
look later today when it's cooled off a bit - it did stay in all night
and heated the house this morning.

Thanks,

Gordon

In article ,
Gordon Henderson writes:
In article ,
Harry Bloomfield wrote:
Gordon Henderson explained :
Any clues of what I can do myself before calling a man in? It looks
relatively straightforward from what I can see - I can identify the pilot
feed to the manifold, as well as the thermocouple - I'd not hesitate to
replace either if they were at fault - but I've no real experience of
this sort of fault - what's it likely to be - the pilot itself or the
thermocouple - or maybe something else?

Check the condition of the 'nose' of the thermocouple, see if it looks
burnt. Check it is properly in the flame, check the draft shield is
properly placed to stop the wind or drafts blowing it out and that the
brass nut is not loose where it enters the gas valve.

If the flame looks poor, the jet could be sooted up.

Sounds like a bit of TLC might be all that's needed then. I'll have a
look later today when it's cooled off a bit - it did stay in all night
and heated the house this morning.

How long since it was serviced?
Whilst many modern boilers actually work best by not taking them
apart to service too often, open flued boilers such as your back
boiler really do have to be checked over anually, because of the
risk of CO emission if anything goes wrong. A sooted up pilot
jet is a likely symptom of a boiler needing cleaning, because
the soot may have resulted from incomplete combustion (and hence CO)
already. Once such boilers start producing a tiny amount of soot,
that in itself can lead to increased levels as it falls back into
jets and burner air intakes, and the thing can rapidly run away,
sooting itself up at a faster and faster rate.
Just cleaning the pilot jet isn't really safe enough.

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

In article ,
Andrew Gabriel wrote:
In article ,
Gordon Henderson writes:
In article ,
Harry Bloomfield wrote:
Gordon Henderson explained :
Any clues of what I can do myself before calling a man in? It looks
relatively straightforward from what I can see - I can identify the pilot
feed to the manifold, as well as the thermocouple - I'd not hesitate to
replace either if they were at fault - but I've no real experience of
this sort of fault - what's it likely to be - the pilot itself or the
thermocouple - or maybe something else?

Check the condition of the 'nose' of the thermocouple, see if it looks
burnt. Check it is properly in the flame, check the draft shield is
properly placed to stop the wind or drafts blowing it out and that the
brass nut is not loose where it enters the gas valve.

If the flame looks poor, the jet could be sooted up.

Sounds like a bit of TLC might be all that's needed then. I'll have a
look later today when it's cooled off a bit - it did stay in all night
and heated the house this morning.

How long since it was serviced?

Spring last year, so about 9 months.. I watched him do it - the thing
was spotless inside bar some dust on the floor - and it looks fairly
clean now, as far as I can tell, not having taken the fire off yet -
I can see the pilot and gas burner pan from underneath.

Whilst many modern boilers actually work best by not taking them
apart to service too often, open flued boilers such as your back
boiler really do have to be checked over anually, because of the
risk of CO emission if anything goes wrong. A sooted up pilot
jet is a likely symptom of a boiler needing cleaning, because
the soot may have resulted from incomplete combustion (and hence CO)
already. Once such boilers start producing a tiny amount of soot,
that in itself can lead to increased levels as it falls back into
jets and burner air intakes, and the thing can rapidly run away,
sooting itself up at a faster and faster rate.
Just cleaning the pilot jet isn't really safe enough.

Having observed first-hand the effects of CO posioning on a diving buddy,
(admittedly accellerated due to the depth we were at) it's not an area
I'm going to muck about in - if I'm at all unsure, I'm calling a man in!

But thinking now - I'm wondering if it's something as silly as wind
direction - our log burners are making weird noises this week - there is
a cowl on the chimney it's under, but it still felt a bit draughty under
there when I looked this morning. We have all sorts of weird rooftops and
chimney arrangements here... (And there is a whopping great hole in the
room to the outside alleyway covered in grills for ventilation in the room
it's in) Our old coal-fired rayburn cooker used to regularly blow-back
before we replaced it and put a new whirly cowl on it's chimney...

Cheers,

Gordon