To quote you, "Note that if running the boiler from the genny you will
probably need to make sure that earthing is correctly connected for the
flame sensing to work properly. So basically set the genny up with an
earth spike like a TT system, and tie one leg of its output to the earth."

Well, that turned out to apply in the case of my boiler, but why? Can
you explain it slowly and simply? Why does the flame sensing need this?

Bill

On 10/12/2013 00:37, Bill Wright wrote:
To quote you, "Note that if running the boiler from the genny you will
probably need to make sure that earthing is correctly connected for the
flame sensing to work properly. So basically set the genny up with an
earth spike like a TT system, and tie one leg of its output to the earth."

Well, that turned out to apply in the case of my boiler, but why? Can
you explain it slowly and simply? Why does the flame sensing need this?

Bill

Dunno exactly - it's something to do with flame ionisation rectifying
the signal or something.

Also, as far as I can see on my 2 boilers, the return path for the spark
is via the casing, so if this isn't connected to one side of the supply
- preferably the neutral(!) - there's no conductivity. Similar, I
suppose, to a car engine - where the engine casting needs to be
connected to the -ve side of the battery for the spark plugs (and other
electrics) to work.
--
Cheers,
Roger
____________
Please reply to Newsgroup. Whilst email address is valid, it is seldom
checked.

In article ,
Roger Mills writes:
On 10/12/2013 00:37, Bill Wright wrote:
To quote you, "Note that if running the boiler from the genny you will
probably need to make sure that earthing is correctly connected for the
flame sensing to work properly. So basically set the genny up with an
earth spike like a TT system, and tie one leg of its output to the earth."

Well, that turned out to apply in the case of my boiler, but why? Can
you explain it slowly and simply? Why does the flame sensing need this?

Bill

Dunno exactly - it's something to do with flame ionisation rectifying
the signal or something.

Also, as far as I can see on my 2 boilers, the return path for the spark
is via the casing, so if this isn't connected to one side of the supply
- preferably the neutral(!) - there's no conductivity. Similar, I
suppose, to a car engine - where the engine casting needs to be
connected to the -ve side of the battery for the spark plugs (and other
electrics) to work.

Yes, it effectively rus between live and earth (far too small a current
to trip an RCD though).

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

Roger Mills wrote:
On 10/12/2013 00:37, Bill Wright wrote:
To quote you, "Note that if running the boiler from the genny you will
probably need to make sure that earthing is correctly connected for the
flame sensing to work properly. So basically set the genny up with an
earth spike like a TT system, and tie one leg of its output to the
earth."

Well, that turned out to apply in the case of my boiler, but why? Can
you explain it slowly and simply? Why does the flame sensing need this?

Bill

Dunno exactly - it's something to do with flame ionisation rectifying
the signal or something.

Also, as far as I can see on my 2 boilers, the return path for the spark
is via the casing, so if this isn't connected to one side of the supply
- preferably the neutral(!) - there's no conductivity. Similar, I
suppose, to a car engine - where the engine casting needs to be
connected to the -ve side of the battery for the spark plugs (and other
electrics) to work.

I can confirm this having had to reverse engineer the Potterton Netaheat
board to fault find. Feeds live through .001uf capacitor and 1M
resistor into the flame and looks for a DC component. Presumably would
not work if L & N were reversed at the supply.

Chris K

On Tue, 10 Dec 2013 00:37:24 +0000, Bill Wright
wrote:

To quote you, "Note that if running the boiler from the genny you will
probably need to make sure that earthing is correctly connected for the
flame sensing to work properly. So basically set the genny up with an
earth spike like a TT system, and tie one leg of its output to the earth."

Well, that turned out to apply in the case of my boiler, but why? Can
you explain it slowly and simply? Why does the flame sensing need this?

Bill

smug
I knew about this anomaly, but only through reading this group.
/smug

--
Graham.

%Profound_observation%

This thread reminds me that I don't think I've seen anything from Geoff.
A search on my newsbase looks like last posting was 16th May, unless he's
changed his alias and I've missed it?

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

On Tuesday, December 10, 2013 12:37:24 AM UTC, Bill Wright wrote:


Well, that turned out to apply in the case of my boiler, but why? Can

you explain it slowly and simply? Why does the flame sensing need this?



Bill

I don't know much about boilers, but it sounds like the boiler, or this particular component of it, doesn't like floating earth generators. In the same way that many caravanners found out that their generator keeps tripping out the RCD, until tie the earth down.

Andrew Gabriel wrote:

This thread reminds me that I don't think I've seen anything from Geoff.
A search on my newsbase looks like last posting was 16th May, unless he's
changed his alias and I've missed it?

No, I called in in August to pick up a pcb, a busy personal and business
life, and why spend time reading this group with the amount of idiots
and trolls here, so he doesnt bother much/ at all now.

On 10/12/2013 11:20, Chris K wrote:
Roger Mills wrote:
On 10/12/2013 00:37, Bill Wright wrote:
To quote you, "Note that if running the boiler from the genny you will
probably need to make sure that earthing is correctly connected for the
flame sensing to work properly. So basically set the genny up with an
earth spike like a TT system, and tie one leg of its output to the
earth."

Well, that turned out to apply in the case of my boiler, but why? Can
you explain it slowly and simply? Why does the flame sensing need this?

Bill

Dunno exactly - it's something to do with flame ionisation rectifying
the signal or something.

Also, as far as I can see on my 2 boilers, the return path for the spark
is via the casing, so if this isn't connected to one side of the supply
- preferably the neutral(!) - there's no conductivity. Similar, I
suppose, to a car engine - where the engine casting needs to be
connected to the -ve side of the battery for the spark plugs (and other
electrics) to work.

I can confirm this having had to reverse engineer the Potterton Netaheat
board to fault find. Feeds live through .001uf capacitor and 1M
resistor into the flame and looks for a DC component. Presumably would
not work if L & N were reversed at the supply.

What the excellent posts above said really ;-)


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Tue, 10 Dec 2013 07:46:17 -0800 (PST), Road_Hog
wrote:

On Tuesday, December 10, 2013 12:37:24 AM UTC, Bill Wright wrote:


Well, that turned out to apply in the case of my boiler, but why? Can

you explain it slowly and simply? Why does the flame sensing need this?



Bill

I don't know much about boilers, but it sounds like the boiler, or this particular component of it, doesn't like floating earth generators. In the same way that many caravanners found out that their generator keeps tripping out the RCD, until tie the earth down.


I'm finding it hard to understand why that might happen, a floating
generator would look like a supply from an isolating transformer.



--
Graham.

%Profound_observation%

In message , Andrew Gabriel
writes
This thread reminds me that I don't think I've seen anything from Geoff.
A search on my newsbase looks like last posting was 16th May, unless he's
changed his alias and I've missed it?

No I've not seen any posts from him either. Though did notice a post
from what I think was him on an DIY forum recently

--
Chris French

Andrew Gabriel wrote:

Yes, it effectively rus between live and earth (far too small a current
to trip an RCD though).


I wondered about the RCD aspect. What's the current?

Bill

Graham. wrote:
On Tue, 10 Dec 2013 00:37:24 +0000, Bill Wright
wrote:

To quote you, "Note that if running the boiler from the genny you will
probably need to make sure that earthing is correctly connected for the
flame sensing to work properly. So basically set the genny up with an
earth spike like a TT system, and tie one leg of its output to the earth."

Well, that turned out to apply in the case of my boiler, but why? Can
you explain it slowly and simply? Why does the flame sensing need this?

Bill

smug
I knew about this anomaly, but only through reading this group.
/smug

And me.

Bill

In article , Andrew Gabriel
writes
In article ,
Roger Mills writes:
On 10/12/2013 00:37, Bill Wright wrote:
To quote you, "Note that if running the boiler from the genny you will
probably need to make sure that earthing is correctly connected for the
flame sensing to work properly. So basically set the genny up with an
earth spike like a TT system, and tie one leg of its output to the earth."

Well, that turned out to apply in the case of my boiler, but why? Can
you explain it slowly and simply? Why does the flame sensing need this?

Bill

Dunno exactly - it's something to do with flame ionisation rectifying
the signal or something.

Also, as far as I can see on my 2 boilers, the return path for the spark
is via the casing, so if this isn't connected to one side of the supply
- preferably the neutral(!) - there's no conductivity. Similar, I
suppose, to a car engine - where the engine casting needs to be
connected to the -ve side of the battery for the spark plugs (and other
electrics) to work.

Yes, it effectively rus between live and earth (far too small a current
to trip an RCD though).

Not entirely convinced on this one, my boiler runs on a transformer
isolated supply and I assume the spark generator/flame sense circuitry
does the same so I'm not sure why the earthing or supply polarity is so
important.
--
fred
it's a ba-na-na . . . .

On 10/12/2013 21:09, Bill Wright wrote:
Andrew Gabriel wrote:

Yes, it effectively rus between live and earth (far too small a current
to trip an RCD though).


I wondered about the RCD aspect. What's the current?

low fractions of a mA...


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Tue, 10 Dec 2013 19:48:33 +0000, chris French
wrote:

No I've not seen any posts from him either. Though did notice a post
from what I think was him on an DIY forum recently

He is alive and well but up to his ears in expanding his empire into
an adjacent unit.

John Rumm wrote:
On 10/12/2013 21:09, Bill Wright wrote:
Andrew Gabriel wrote:

Yes, it effectively rus between live and earth (far too small a current
to trip an RCD though).


I wondered about the RCD aspect. What's the current?

low fractions of a mA...

Ah. I see.

Bill

On 10/12/2013 21:41, fred wrote:
In article , Andrew Gabriel
writes
In article ,
Roger Mills writes:
On 10/12/2013 00:37, Bill Wright wrote:
To quote you, "Note that if running the boiler from the genny you will
probably need to make sure that earthing is correctly connected for the
flame sensing to work properly. So basically set the genny up with an
earth spike like a TT system, and tie one leg of its output to the
earth."

Well, that turned out to apply in the case of my boiler, but why? Can
you explain it slowly and simply? Why does the flame sensing need this?

Bill

Dunno exactly - it's something to do with flame ionisation rectifying
the signal or something.

Also, as far as I can see on my 2 boilers, the return path for the spark
is via the casing, so if this isn't connected to one side of the supply
- preferably the neutral(!) - there's no conductivity. Similar, I
suppose, to a car engine - where the engine casting needs to be
connected to the -ve side of the battery for the spark plugs (and other
electrics) to work.

Yes, it effectively rus between live and earth (far too small a current
to trip an RCD though).

Not entirely convinced on this one, my boiler runs on a transformer
isolated supply and I assume the spark generator/flame sense circuitry
does the same so I'm not sure why the earthing or supply polarity is so
important.

You could try temporarily disconnecting the boiler's earth wire, and
then see whether it still works.
--
Cheers,
Roger
____________
Please reply to Newsgroup. Whilst email address is valid, it is seldom
checked.

" John Rumm on boilers"

On 10/12/2013 00:37, Bill Wright wrote
Well, that turned out to apply in the case of my boiler



How dissapointing.

I'd hoped to be reading about your exploits with er,
differently-attactive women.

I had my tales all ready to tell, but perhaps for another day :-)